To Convert the Given String to Propercase

If string is not in proper case i.e. if a particular name's all letters are in upper case or lower case, so this code will convert it to proper case.

public class ConvertToProperCase {
 
 public static String convertToProper(String strToConvert) throws java.io.IOException{
   
  //get lower case string
  java.io.StringReader str = new java.io.StringReader(strToConvert.toLowerCase());
   boolean precededBySpace = true;
   StringBuffer properCase = new StringBuffer();    
    while(true) {     
     //read string character by character
   int i = str.read();
     if (i == -1)  break;      
    char c = (char)i;
    if (c == ' ' || c == '"' || c == '(' || c == '.' || c == '/' || c == '\' || c == ',') {
      properCase.append(c);
      precededBySpace = true;
      } else {
      if (precededBySpace) {
       //convert first character to proper
     properCase.append(Character.toUpperCase(c));
      } else { 
         // append rest character
      properCase.append(c); 
      }
      precededBySpace = false;
   }
   }
   
  return properCase.toString();    
   
 }
 //main code
 public static void main(String[] args) {
  
  try {
   //call convertToProper method
   System.out.println(convertToProper("1jf94osl TEST TEST test test., MIKE, BRADD, blair"));
  } catch (java.io.IOException e) {
   System.out.println("Exception:" + e);
  }
 }
 
 
}

[ Read More ]

Excel report generator based on the Input provided through an xml file

This tool can generate one or more xls report based on the input provided inside a xml file.

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import org.apache.poi.hssf.util.Region;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.w3c.dom.Node;
import org.w3c.dom.Element;
import java.io.File;
import java.io.FileOutputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

/**
* This java class will read the xml file and generate the excel sheet based on the input parameter 
* provided to it.  
* 
* 
*/
public class ReadXmlFile {

 public static void main(String argv[]) {
  Connection con = null;
  try {
   String __runId = argv[0];
   String __runIdArr[] = __runId.split(",");
   if (__runIdArr.length > 0) {
    for (int i = 0; i < __runIdArr.length; i++) {
     String __filePath = "C:\excel\test1.xml";
     File fXmlFile = new File(__filePath);
     DocumentBuilderFactory dbFactory = DocumentBuilderFactory
       .newInstance();
     DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
     Document doc = dBuilder.parse(fXmlFile);
     doc.getDocumentElement().normalize();
     System.out.println("Root element :"
       + doc.getDocumentElement().getNodeName());
     NodeList nList = doc.getElementsByTagName("data");
     System.out.println("-----------------------");
     File f = new File("C:\excel\data_import_"+__runIdArr[i]+".xls");
     if (f.createNewFile()) {
      System.out
        .println("File has been created successfully");
     }
     FileOutputStream fileOut = new FileOutputStream(f);
     HSSFWorkbook hwb = new HSSFWorkbook();
     for (int temp = 0; temp < nList.getLength(); temp++) {

      Node nNode = nList.item(temp);
      if (nNode.getNodeType() == Node.ELEMENT_NODE) {

       Element eElement = (Element) nNode;
       String __sheetName = getTagValue("sheetname",
         eElement);
       String __columns = getTagValue("column", eElement);
       String __query = getTagValue("query", eElement);
       // String __runId = getTagValue("runid", eElement);
       con = DBConnection.getConnection();
       if (createSheet(hwb, __sheetName, con, __query,
         __columns, __runIdArr[i])) {
        System.out
          .println(__sheetName
            + " sheet has been created successfully.");
       }

      }
     }
     hwb.write(fileOut);
    }
   }
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   try {
    con.close();
   } catch (Exception e) {
    e.printStackTrace();
   }
  }

  System.out.println("File has been generated successfully.");
  System.exit(1);
 }

 /**
  * @depricated.
  * @param sTag String Object.
  * @param eElement Element object
  * @return returns string object.
  */
 private static String getTagValue(String sTag, Element eElement) {
  NodeList nlList = eElement.getElementsByTagName(sTag).item(0)
    .getChildNodes();
  Node nValue = (Node) nlList.item(0);
  return nValue.getNodeValue();
 }

 /**
  * This method will create the excel sheet based on queries has been written inside the xml file.
  * @param hwb Inatance of HSSFWorkbook
  * @param sheetName Instance of 
  * @param con String
  * @return returns boolean values.
  * @throws Exception
  */
 private static boolean createSheet(HSSFWorkbook hwb, String sheetName,
   Connection con, String query, String columns, String runId)
   throws Exception {
  boolean __sheetstatus = false;
  HSSFSheet sheet = hwb.createSheet(sheetName);
  HSSFRow rowhead = sheet.createRow((int) 1);
  int count = 0;
  HSSFFont font = hwb.createFont();
  font.setFontHeightInPoints((short) 10);
  font.setFontName(HSSFFont.FONT_ARIAL);
  HSSFCellStyle headerCell = setHeaderCell(hwb, font);
  String columnsArr[] = columns.split(";");
  for (int i = 0; i < columnsArr.length; i++) {
   setHeadColumnValue(sheet, rowhead, headerCell, columnsArr[i],
     count, 75);
   count++;
  }
  PreparedStatement psEventCount = null;
  ResultSet rsEventType = null;
  try {
   psEventCount = con.prepareStatement(query.replaceAll("#", runId));
   rsEventType = psEventCount.executeQuery();
   int rowCount = 2;
   HSSFCellStyle setStringCell = setStringCell(hwb);
   while (rsEventType.next()) {
    int __count = 0;
    HSSFRow currentRowhead = sheet.createRow((short) rowCount);
    for (int i = 0; i < columnsArr.length; i++) {
     String __equipmentselNumber = rsEventType
       .getString(columnsArr[i]);
     setHeadColumnValue(sheet, currentRowhead, setStringCell,
       __equipmentselNumber, __count, 75);
     __count++;
    }
    rowCount++;
   }
  } catch (Exception e) {
   e.printStackTrace();
   throw e;
  } finally {
   rsEventType.close();
   psEventCount.close();

  }
  __sheetstatus = true;
  return __sheetstatus;
 }

 /**
  * @This method will organize the xls cell values and style of that.
  * @param wb Instance of HSSFWorkbook
  * @param font Inatance of HSSFFont 
  * @return Instance of String.
  */
 private static HSSFCellStyle setHeaderCell(HSSFWorkbook wb, HSSFFont font) {
  HSSFCellStyle headerCell = wb.createCellStyle();
  font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
  // headerCell.setAlignment(HSSFCellStyle.ALIGN_LEFT);
  headerCell.setVerticalAlignment(HSSFCellStyle.VERTICAL_TOP);
  headerCell.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
  headerCell.setFillForegroundColor(HSSFColor.LEMON_CHIFFON.index);
  headerCell.setFont(font);
  headerCell.setBorderBottom(HSSFCellStyle.BORDER_THIN);
  headerCell.setBorderLeft(HSSFCellStyle.BORDER_THIN);
  headerCell.setBorderTop(HSSFCellStyle.BORDER_THIN);
  headerCell.setBorderRight(HSSFCellStyle.BORDER_THIN);
  headerCell.setWrapText(true);
  return headerCell;
 }

 /**
  * @This method will organize the xls cell values and style of that.
  * @param wb Instance of HSSFWorkbook
  * @return returns String instance.
  */
 private static HSSFCellStyle setStringCell(HSSFWorkbook wb) {
  HSSFCellStyle stringCell = wb.createCellStyle();
  stringCell.setAlignment(HSSFCellStyle.ALIGN_LEFT);// "#,##0"
  stringCell.setBorderBottom(HSSFCellStyle.BORDER_THIN);
  stringCell.setBorderLeft(HSSFCellStyle.BORDER_THIN);
  stringCell.setBorderTop(HSSFCellStyle.BORDER_THIN);
  stringCell.setBorderRight(HSSFCellStyle.BORDER_THIN);
  stringCell.setLocked(false);
  stringCell.setWrapText(true);
  return stringCell;
 }

 /**
  * This method will set the head columns values.
  * @param sheet Instance of HSSFSheet 
  * @param row  Instance of HSSFRow 
  * @param style Instance of HSSFCellStyle
  * @param value Instance of String
  * @param colNo Instance of int.
  * @param width Instance of of int.
  */
 public static void setHeadColumnValue(HSSFSheet sheet, HSSFRow row,
   HSSFCellStyle style, String value, int colNo, int width) {
  HSSFCell cellt = row.createCell((short) colNo);
  sheet.addMergedRegion(new Region(0, (short) colNo, 0,
    (short) (colNo + 2)));
  cellt.setCellStyle(style);
  cellt.setCellValue(value);
  sheet.setColumnWidth((short) colNo, (short) (100 * width));
 }

}
import java.sql.*;
public class DBConnection {
public static Connection getConnection(){
 Connection con=null;
 try{
 Class.forName("oracle.jdbc.driver.OracleDriver");
 //QA
 //String url = "jdbc:oracle:thin:@etpcamq1.energy.ge.com:1521:etpcamq1";
 //con = DriverManager.getConnection(url,"TBCAM","cam34etpq1");

 String url =""
 con = DriverManager.getConnection(url,"","");
 
 }catch(Exception e){
  e.printStackTrace();
 }
 return con;
 }
}

[ Read More ]

Recursivey listing files and folders in java

This code snippet lists all the files and folders including the files in subdirectories present in the given path at any level recursively and displays in a tree structure

import java.io.File;

public class FileStructure {

  int tabCounter = 0;

  // obtain the list of files and folders in particular location
  public void listFilesAndFolders(String folder) {

    File file = new File(folder);

    if (!file.exists() || !file.isDirectory()) {

      System.out.println("Parameter is not a directory");
      System.exit(1);

    }

    File[] fileArray = file.listFiles();

    for (int i = 0; i < fileArray.length; i++) {

      if (fileArray[i].isDirectory()) {

        System.out.println(getTabs() + "- " + fileArray[i].getName());
        tabCounter++;
        listFilesAndFolders(fileArray[i].getAbsolutePath());

      }
      else {

        System.out.println(getTabs() + fileArray[i].getName());
      }
    }
    tabCounter--;

  }
  // provide a tab space to represent tree structure
  private String getTabs() {

    StringBuffer buffer = new StringBuffer();
    for (int i = 0; i < tabCounter; i++)
      buffer.append("\t");

    return buffer.toString();
  }

  public static void main(String[] args) {

    FileStructure fileStructure = new FileStructure();
    fileStructure.listFilesAndFolders("C:\\temp");
  }
}

[ Read More ]

calculate the free disk space

To calculate available disk space using Java   

import java.io.IOException; 
  
import org.apache.commons.io.FileSystemUtils; 
  
public class DiskSpace { 
    public static void main(String[] args) { 
        try { 
  
            //calculate free disk space 
            double freeDiskSpace = FileSystemUtils.freeSpaceKb("C:");  
  
            //convert the number into gigabyte 
            double freeDiskSpaceGB = freeDiskSpace / 1024 / 1024; 
  
            System.out.println("Free Disk Space (GB):" + freeDiskSpaceGB); 
        } catch (IOException e) { 
            e.printStackTrace(); 
        } 
    } 
}

[ Read More ]

Dictionary Program to obtain meaning of words using java

It is a program to obtain meaning of words which are redirected to google as parameters. The results are fetched and printed using json object in java.   

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import java.nio.charset.Charset;

import javax.swing.JOptionPane;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
public class Dictonary
{
 public static void main(String args[]) throws Exception
 {
 String str = null;
 System.out.println("running");;
 str = JOptionPane.showInputDialog("Enter the string"); 
 System.setProperty("http.proxyHost", "192.168.0.17");
 System.setProperty("http.proxyPort", "8080");
 JSONObject json = readJsonFromUrl("http://www.google.com/dictionary/json?callback=dict_api.callbacks.id100&q="+str+"&sl=en&tl=en&restrict=pr%2Cde&client=te");
 JSONArray json1 = json.getJSONArray("webDefinitions");
 JSONArray json2 = ((JSONObject)json1.get(0)).getJSONArray("entries");
 System.out.println("MEANINGS OF  "+str);
 for(int i=0;i<json2.length();i++)
 {
  JSONArray jobarray =((JSONObject)json2.get(i)).getJSONArray("terms");
  for(int j=0;j<jobarray.length();j++)
  {
   JSONObject job = jobarray.getJSONObject(j);
      String stri =  (String)job.get("type");
      if(stri.equals("text"))
      {
       System.out.println(job.get("text"));
      }
  }
  System.out.println("");
 }
 

 }
 public static JSONObject readJsonFromUrl(String url) throws IOException, JSONException 
 {
     InputStream is = new URL(url).openStream();
     try {
      
       BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8")));
       String jsonText = readAll(rd);
     //  System.out.println("char 1  "+jsonText.trim());
        jsonText=  jsonText.substring(jsonText.indexOf('(')+1,jsonText.lastIndexOf(')'));
    //   System.out.println("char 2  "+jsonText.trim());
       JSONObject json = new JSONObject(jsonText.trim());
       return json;
     } finally {
       is.close();
     }

}
 private static String readAll(Reader rd) throws IOException 
 {
     StringBuilder sb = new StringBuilder();
     int cp;
     while ((cp = rd.read()) != -1) {
       sb.append((char) cp);
     }
     return sb.toString();
   }

}

[ Read More ]

Efficient retrieval of Keys using given Values in the Map

This asset provides a reusable code which can be used to retrieve the Keys when Values are given in Java maps.

BidiMap bidimap = new DualHashBidiMap();

bidimap.putAll(theMap);  
  
String myKey= bidimap.inverseBidiMap().get("Mumbai").toString();

System.out.println("The Key is :"  +  myKey) ;

[ Read More ]

To Create a collection using the Given array

This code snippet is useful for converting when a lot of array is given and needs in collection.

import java.util.*;
import java.io.*;

public class ArrayToCollection{
   public static void main(String args[]) 
   throws IOException{
      BufferedReader in = new BufferedReader
      (new InputStreamReader(System.in));
      System.out.println("Number of elements 
      you want to add to the array: ");
      int n = Integer.parseInt(in.readLine());
      String[] name = new String[n];
      for(int i = 0; i < n; i++){
         name[i] = in.readLine();
      }
      List list = Arrays.asList(name); 
      System.out.println();
      for(String li: list){
         String str = li;
         System.out.print(str + " ");
      }
   }
}

[ Read More ]

Replace a element in the list

when there is a lot of array or list is provided you need to replace a particular element by searching automatically.   

import java.util.*;

public class Main {
   public static void main(String[] args) {
      List list = Arrays.asList("this is the list to be replaced one Two three Four five six
      one three Four
".split(" "));
      System.out.println("List :"+list);
      Collections.replaceAll(list, "one", "hundread");
      System.out.println("replaceAll: " + list);
   }
}

[ Read More ]

Grouping products or items based on common categories

The objective is to group the items together based on common categories.

For e.g.1, if there are two items(7000090069,7000090070) associated with three categories (264433,264431,264432) as below :

7000090069 --> 264431

7000090069 --> 264433

7000090070 --> 264433

7000090070 --> 264432

then the output will be 7000090069,7000090070_264433,264431,264432

e.g.2, if there are two items(7000090069,7000090070) associated with three categories

(264431,264432) as below :

7000090069 --> 264431

7000090070 --> 264432

then the output will be 7000090069_264431 and 7000090070_264432 in a list.

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class Test {

 /**
  * This class contains items and categories. 
  * The objective is to group the items together based on common categories.
  * For e.g.1, if there are two items(7000090069,7000090070) associated with three categories (264433,264431,264432) as below :
  *   7000090069 --> 264431
  *   7000090069 --> 264433
  *   7000090070 --> 264433
  *   7000090070 --> 264432
  *   then the output will be 7000090069,7000090070_264433,264431,264432
  *   
  *   e.g.2, if there are two items(7000090069,7000090070) associated with three categories (264431,264432) as below :
  *   7000090069 --> 264431
  *   7000090070 --> 264432
  *   then the output will be 7000090069_264431 and 7000090070_264432 in a list.
  */
 static class A {
  long item;
  long category;

  public A(long q, long f) {
   super();
   this.item = q;
   this.category = f;
  }

  public long getItem() {
   return item;
  }

  public void setItem(long q) {
   this.item = q;
  }

  public long getCategory() {
   return category;
  }

  public void setCategory(long f) {
   this.category = f;
  }
 }

 public static void main(String[] args) {
  A[] arr = new A[9];

  arr[0] = new A(7000089688L, 264431);
  arr[1] = new A(7000089707L, 264432);
  arr[2] = new A(7000090069L, 264433);
  arr[3] = new A(7000090047L, 264431);
  arr[4] = new A(7000090051L, 264432);
  arr[5] = new A(7000084083L, 264432);
  arr[6] = new A(7000089688L, 264432);
  arr[7] = new A(7000090070L, 264433);
  arr[8] = new A(7000090070L, 264431);

  List<String> list = new ArrayList<String>();
  int length = 0;

  for (int i = 0; i < arr.length; i++) {
   length = list.size();
   A a = arr[i];
   if (list.isEmpty()) {
    list.add(String.valueOf(a.getItem()) + "_"
      + String.valueOf(a.getCategory()));
    continue;
   }
   boolean added = false;
   for (int j = 0; j < length; j++) {
    String str = list.get(j);
    String[] strArr = str.split("_");
    if (!strArr[0].contains(String.valueOf(a.getItem()))
      && strArr[1].contains(String.valueOf(a.getCategory()))) {
     list.set(j, strArr[0] + "," + String.valueOf(a.getItem())
       + "_" + strArr[1]);
     added = true;
    } else if (strArr[0].contains(String.valueOf(a.getItem()))
      && !strArr[1].contains(String.valueOf(a.getCategory()))) {
     boolean isRemoved = false;
     for (int k = 0; k < length; k++) {
      String str1 = list.get(k);
      String[] strings = str1.split("_");
      if (strings[1]
        .contains(String.valueOf(a.getCategory()))) {
       list.set(
         j,
         strArr[0]
           + ","
           + strings[0]
           + "_"
           + (strArr[1].contains(strings[1]) ? strArr[1]
             : strArr[1] + ","
               + strings[1]));
       list.remove(k);
       length = list.size();
       isRemoved = true;
      }
     }
     if (!isRemoved) {
      list.set(
        j,
        strArr[0] + "_" + strArr[1] + ","
          + String.valueOf(a.getCategory()));
     }
     added = true;
    } else if (strArr[0].contains(String.valueOf(a.getItem()))
      && strArr[1].contains(String.valueOf(a.getCategory()))) {
     added = true;
    }
   }
   if (!added) {
    list.add(String.valueOf(a.getItem()) + "_"
      + String.valueOf(a.getCategory()));
   }
  }

  for (Iterator iterator = list.iterator(); iterator.hasNext();) {
   String string = (String) iterator.next();
   System.out.println(string);
  }
 }
}

[ Read More ]

List elements movement or rotation

Using the java collection we can rotate or move the elements of the list.

import java.util.*;

public class Main {
   public static void main(String[] args) {
      List list = Arrays.asList("This is the statement you want to rotate in different phrases".split(" "));
      System.out.println("List :"+list);
      Collections.rotate(list, 3);
      System.out.println("rotate: " + list);
   }
}

[ Read More ]

Transferring macros using java

Macros of excel can be executed using vbscript calling from a java file

using apachepoi and jexcel api we can read and write in excel file using this jars but to read macros we need to run vb script and this method calls vbscript and transfer macros....or other way around use component to change excel file in to xml file and then load it to your project

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
 
public class AccessMacro {
 
    private static void createAndShowGUI(){
 
        JFrame frame1 = new JFrame("Run Macro");
        frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        JButton button = new JButton(" >> JavaProgrammingForums.com <<");
        // Add action listener to button
        button.addActionListener(new ActionListener() {
 
 
            public void actionPerformed(ActionEvent e) {
                // Execute when button is pressed
                try{
                Runtime.getRuntime().exec("cmd /c start runmacro.vbs");
                }catch(Exception a){
                    System.out.println("Problem opening runmacro script!");
                }
            }
        });
 
 
        frame1.getContentPane().add(button);
        frame1.pack();
        frame1.setVisible(true);
    }
 
    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}

[ Read More ]

Getting dates without time portion

This code snippet helps to retrieve a particular date without its time portion.

public static Date getDate(Date inDate){
  if(inDate != null){
                       Calendar objCalendar = new GregorianCalendar();
   objCalendar.setTime(inDate);
   objCalendar.set(Calendar.HOUR_OF_DAY, 0);
   objCalendar.set(Calendar.MINUTE, 0); 
   objCalendar.set(Calendar.SECOND, 0); 
   objCalendar.set(Calendar.MILLISECOND, 0); 
   return (objCalendar.getTime());
  }else{
   return null;
  }
 }

[ Read More ]

Demonstration of Multi threading

This is just a code snippet which depicts how a multi-threaded application works.

There is N number of files; we need to perform same action on all the files. This code depicts how multiple files are read on simultaneous threads, processing and writing it to new files

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.util.List;


public class FileProcessorThread implements Runnable {

  /** The constant DONE. */
 private static final String CONSTANT_DONE = "DONE".trim();

  /** The file details list. */
 private List<FileDeatils> fileDeatilsList;

 /**
  * The constructor for the thread.
  * @param fileDeatilsList
  */
 public FileProcessorThread(List<FileDeatils> fileDeatilsList) {
  super();
  this.fileDeatilsList = fileDeatilsList;
 }

 @Override
 public void run() {

  Boolean stopIndicator = false;
  FileDeatils fileToProcess;
  while (!stopIndicator) {
   fileToProcess = getUnProcessedFile(fileDeatilsList);
   if (fileToProcess != null) {
    lockFile(fileToProcess);
    readProcessWrite(fileToProcess);
   } else {
    // if nothing to process stop indicator would be set to true and Thread will come to END.
    System.out.println(Thread.currentThread().getName() + "_ Thread Stopping..");
    stopIndicator = true;
   }
  }
 }
 
 /**
  * to check processed or not.
  * @param fileDeatils
  * @return boolean
  */
 private boolean isProcessedChkViaFlg(FileDeatils fileDeatils) {

  boolean isProcessed = false;
  synchronized (fileDeatils) {
   if (fileDeatils.isProcessed()) {
    isProcessed = true;
   }
   Thread t = Thread.currentThread();
   System.out.println("Scan to verify processed record " + t.getName()
     + "  Processed " + isProcessed);
  }
  return isProcessed;
 }

 /** get unprocessed file
  * @param fileDeatilsList
  * @return
  */
 private FileDeatils getUnProcessedFile(List<FileDeatils> fileDeatilsList) {

  FileDeatils fileToProcess = null;

  for (FileDeatils fileDeatils : fileDeatilsList) {
   if (!isProcessedChkViaFlg(fileDeatils)) {
    fileToProcess = fileDeatils;
    break;
   }
  }
  return fileToProcess;
 }

 /**
  * Lock the file by putting a DONE at the end of the file.
  * @param fileDeatils
  */
 public void lockFile(FileDeatils fileDeatils) {

  try {
   synchronized (fileDeatils) {
    if (!fileDeatils.isProcessed()) {
     Writer inPutFileWriter = new BufferedWriter(new FileWriter(
       fileDeatils.getInputFileName(), true));
     inPutFileWriter.append(CONSTANT_DONE+"_"+Thread.currentThread().getName());
     fileDeatils.setProcessed(true);
     inPutFileWriter.close();
    }
   }
  } catch (IOException e) {
   e.printStackTrace();
  } 
 }
 
 /**
  * Read the file and process.
  * @param fileDeatils
  * @return
  */
 public boolean readProcessWrite(FileDeatils fileDeatils) {

  boolean processed = true;
  File inputFile = new File(fileDeatils.getInputFileName());
  File outPutFile = new File(fileDeatils.getOutPutFileName());

  Writer output = null;
  BufferedReader input = null;
  try {
   output = new BufferedWriter(new FileWriter(outPutFile));
   input = new BufferedReader(new FileReader(inputFile));

   String line = null;
   while ((line = input.readLine()) != null) {
    if (line.contains("X")) {
     //Thread t = Thread.currentThread();
     //System.out.println(t.getName()+"_"+line);
     line = line.replace("X", "XXXXXXXXXXXXXX");
    }
    output.write(line);
    output.write("n");
   }
  } catch (IOException e) {
   e.printStackTrace();
   processed = false;
  } finally {
   try {
    output.close();
    input.close();
   } catch (IOException e) {
    e.printStackTrace();
    processed = false;
   }
  }
  return processed;
 }
}




import java.util.List;


public class ControllerThread implements Runnable{

 /** The file details list. */
 private List<FileDeatils> fileDeatilsList;
 
 /** To name the new thread. */
 private int count = 0;
 
 /** All files are processed or not. */
 private boolean isProcessCompleted = false;
 /**
  * The Constructor.
  * @param fileDeatilsList
  */
 public ControllerThread(List<FileDeatils> fileDeatilsList) {
  super();
  this.fileDeatilsList = fileDeatilsList;
 }


 @Override
 public void run() {

  while (!isProcessCompleted) {

   isProcessCompleted = isProcessingCompleted();
   /* Allow thread to sleep for 1.2 seconds */
   if (!isProcessCompleted) {
    try {
     Thread.sleep(1250);
    } catch (InterruptedException e) {
     e.printStackTrace();
    }

    if (noOfProcessedFiles() < 20) {
     System.out.println("File processed is less than 20 so starting one more thread");
     StringBuilder threadName = new StringBuilder();
     threadName.append("File Copy Adhoc_ThreadIndex:");
     threadName.append(count++);
     ThreadGroup threadGroup = new ThreadGroup("MultipleFileProcessingThread");
     FileProcessorThread fileProcessorThread = new FileProcessorThread(fileDeatilsList);
     Thread thread = new Thread(threadGroup, fileProcessorThread, threadName.toString());
     thread.start();
    }
   } else {
    System.out.println("Stopping Controller Thread !!! ...");
   }
  }
 }
 
 /**
  * to find the processing completed.
  * @return
  */
 private boolean isProcessingCompleted() {
  boolean isCompleted = true;
  synchronized (fileDeatilsList) {
   for (FileDeatils fileDeatils : fileDeatilsList) {
    if (!fileDeatils.isProcessed()) {
     isCompleted = false;
     break;
    }
   }
  }
  return isCompleted;
 }
 
 /**
  * to find the processing completed.
  * @return
  */
 private int noOfProcessedFiles() {
  int completedListCount = 0;
  synchronized (fileDeatilsList) {
   for (FileDeatils fileDeatils : fileDeatilsList) {
    if (fileDeatils.isProcessed()) {
     completedListCount++;
    }
   }
  }
  return completedListCount;
 }
}





public class FileDeatils {
 private String inputFileName;
 private String outPutFileName;
 private boolean processed;
 
 public String getInputFileName() {
  return inputFileName;
 }
 public void setInputFileName(String inputFileName) {
  this.inputFileName = inputFileName;
 }
 public String getOutPutFileName() {
  return outPutFileName;
 }
 public void setOutPutFileName(String outPutFileName) {
  this.outPutFileName = outPutFileName;
 }
 public boolean isProcessed() {
  return processed;
 }
 public void setProcessed(boolean processed) {
  this.processed = processed;
 }
}


/* the initiator which kiks of the action */ 


import java.util.List;


public class Initiator {

 /**
  * To initiate the action.
  * @param noOfConcurrentOperations
  * @param fileDeatilsList
  */
 public void initiate(int noOfConcurrentOperations, List<FileDeatils> fileDeatilsList) {

  for (int i = 1; i < noOfConcurrentOperations; i++) {
   StringBuilder threadName = new StringBuilder();
   threadName.append("File Copy_ThreadIndex:");
   threadName.append(i);
   ThreadGroup threadGroup = new ThreadGroup("MultipleFileProcessingThread");

   FileProcessorThread fileProcessorThread = new FileProcessorThread(fileDeatilsList);
   Thread thread = new Thread(threadGroup, fileProcessorThread, threadName.toString());
   thread.start();
  }
  
  ControllerThread controllerThread = new ControllerThread(fileDeatilsList);
  StringBuilder threadName = new StringBuilder();
  threadName.append("File Copy Control Thread_ThreadIndex ");
  ThreadGroup threadGroup = new ThreadGroup("MultipleFileProcessingThread");
  Thread thread = new Thread(threadGroup, controllerThread,
    threadName.toString());
  thread.start();

 }

}


import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;


public class Init {

 public static void main(String[] args) {
  System.out.println("Started.. creating input file to test");
  Init i = new Init();
  List<FileDeatils> fileDeatilsList = null;
  try {
   fileDeatilsList = i.createInputOutPut();
  } catch (IOException e) {
   e.printStackTrace();
  }
  writeToFile(fileDeatilsList);
  new Initiator().initiate(2, fileDeatilsList);
 }
 
 /**
  * just to create some data for testing, create 22 input files to c:InputTest Folder 
  * @return
  * @throws IOException
  */
 private List<FileDeatils> createInputOutPut() throws IOException {

  List<FileDeatils> fileDeatilsList = new ArrayList<FileDeatils>();
  int noOfInputFiles = 23;

  for (int i = 1; i < noOfInputFiles; i++) {
   FileDeatils fileDeatils = new FileDeatils();
   String inputFileName = "C:\InputTest\Input\INPUT" + i + ".txt";
   String outPutFileName = "C:\InputTest\Output\OUTPUT_" + i + ".txt";
   fileDeatils.setInputFileName(inputFileName);
   fileDeatils.setOutPutFileName(outPutFileName);
   fileDeatilsList.add(fileDeatils);

  }
  return fileDeatilsList;
 }
 
 
 /**
  * this writes some data to the test input file.
  * 
  * @param fileDeatilsList
  */
 public static void writeToFile(List<FileDeatils> fileDeatilsList) {
  String INPUT_STRING = "INPUT";
  int fileCount = 1;
  for (FileDeatils fileDeatils : fileDeatilsList) {
   File inputFile = new File(fileDeatils.getInputFileName());
   Writer output = null;
   int count = 1;
   try {
    output = new BufferedWriter(new FileWriter(inputFile));
    while (true) {
     output.write(INPUT_STRING + "_" + fileCount + "_X");
     output.write("n");
     count++;
     if ((count + (int) new Random().nextInt(5000)) > 1000000) {
      break;
     }
    }
    output.close();
    fileCount++;
   } catch (IOException e) {
    e.printStackTrace();
   }
  }
 }

}

[ Read More ]

Cross site scripting filter

Filter intercepts every request sent to your web application and then cleans any potential script injection. What it basically does is remove all suspicious strings from request parameters (and headers) before returning them to the application.

private String cleanXSS(String paramString)
  {
    if (paramString == null)
      return "";
    String str = paramString;
    str = str.replaceAll("", "");
    Pattern localPattern = Pattern.compile("<script>(.*?)</script>", 2);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("src[rn]*=[rn]*\'(.*?)\'", 42);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("src[rn]*=[rn]*\"(.*?)\"", 42);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("</script>", 2);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("<script(.*?)>", 42);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("eval\((.*?)\)", 42);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("expression\((.*?)\)", 42);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("javascript:", 2);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("vbscript:", 2);
    str = localPattern.matcher(str).replaceAll("");
    localPattern = Pattern.compile("onload(.*?)=", 42);
    str = localPattern.matcher(str).replaceAll("");
    str = str.replaceAll("\(", "&#40;").replaceAll("\)", "&#41;");
    str = str.replaceAll("'", "&#39;");
    str = str.replaceAll("<", "&lt;").replaceAll(">", "&gt;");
    return str;
  }

[ Read More ]

Sorting a List in ascending order

This code snippet sorts a list of objects based on the value of a field of those objects

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class Student implements Comparable {

 private String name;
 private String rollNumber;
 private String department;
// Constructor for the class

public Student(String name,String rollNumber,String department){
 this.name = name;
 this.rollNumber = rollNumber;
 this.department = department;
 
} 
 public String getName() {

  return this.name;
 }

 public void setName(String name) {

  this.name = name;
 }

 public String getRollNumber() {

  return rollNumber;
 }

 public void setRollNumber(String rollNumber) {

  this.rollNumber = rollNumber;
 }

 public String getDepartment() {

  return this.department;
 }

 public void setDepartment(String department) {

  this.department = department;
 }

 //This Function is responsible for sorting.
 
 public int compareTo(Object student1) {
  if (!(student1 instanceof Student))
   throw new ClassCastException("A Student object expected.");

  int rollNumb = Integer.parseInt(((Student) student1).getRollNumber());
  int hostObjrollNumb = Integer.parseInt(this.getRollNumber());
  return hostObjrollNumb - rollNumb;

 }

 
 public static void main(String[] args) {
  // TODO Auto-generated method stub

  List<Student> lstEstDetailsPrio = new ArrayList<Student>();
  
  //Adds data to the objects
  
  Student s1 = new Student("Tom","3","CS");
  Student s2 = new Student("Jerry","1","IT");
  Student s3 = new Student("Merry","4","Electronics");
        
  //Adds objects to the list
  
  lstEstDetailsPrio.add(s1);
  lstEstDetailsPrio.add(s2);
  lstEstDetailsPrio.add(s3);
  
  //Sorts the List
  
  Collections.sort(lstEstDetailsPrio);

 }

}

[ Read More ]

Excel Data To Delimited File Utility

A windows based File converter utility has been developed (with Java) to convert an excel file into a delimited format.

This utility takes two inputs ,need to be provided by the user :

1) The path of the excel file (.xls/.xlt) required to be converted

2) Delimiter to be used (For example : pipe (|), comma (,), dollar ($) )

A delimited file named output_<worksheet>.txt is created ,on the same location as of input excel file. Also ,the utility is able to read multiple worksheets of the excel and the output file(s) should be opened with notepad.   

/*GetUserInput.java*/


import java.io.*;

public class GetUserInput
{  
 /*Method to take excel file path and name input from user*/
 String input()
 {
  System.out.print("Enter excel file name in the pattern C:\FolderName\filename " + "n");
  BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  String inputfile = null;
  try
  {
   inputfile = br.readLine();
  }catch (IOException e) 
   {         
   System.out.println("Error in input file!");        
   System.exit(1);      
   }
  return inputfile;
 }/*Method input closed*/
 
 /*Method to take delimiter to be used from user*/
 String delimiter()
 {
  System.out.print("Enter delimiter to be used " + "n");
  BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
  String delimiter = null;
  try
  {
   delimiter = br.readLine();
  }catch (IOException e) 
  {         
   System.out.println("Error in delimiter!");        
   System.exit(1);      
  }
  return delimiter;
 }/*Method delimiter closed*/
}/*Class closed*/

/****************************************************************************************/
/*ConvertExcelToCSV.java*/

import java.io.*;
import jxl.*;
import java.util.*;
class  ConvertExcelToDelimited
{
 public static void main(String[] args)
 {
  try
  {
   /*To Get the input excel name from user*/
   GetUserInput input1 = new GetUserInput();
   String filename = null;
   filename = input1.input();
   
   /*To Get delimiter to be used from user*/
   GetUserInput input2 = new GetUserInput();
   String user_delimiter = null;
   user_delimiter= input2.delimiter();
   
   /*To Get the output file path from the input excel name*/ 
   File outpath = new File(filename);
   String outputpath = null;
   outputpath = outpath.getParent();
   

   WorkbookSettings ws = new WorkbookSettings();
   ws.setLocale(new Locale("en", "EN"));
   Workbook w = Workbook.getWorkbook(new File(filename),ws);
   
   for (int sheet = 0; sheet < w.getNumberOfSheets(); sheet++)
   {
    /*Objects :
     * 1. To read each sheet 
     * 2. Create output files as per the sheet name in the excel */
    Sheet s = w.getSheet(sheet);
    File f = new File(outputpath+"//output_" + s.getName() + ".txt");
    
    OutputStream os = (OutputStream)new FileOutputStream(f);
    String encoding = "UTF8";
    OutputStreamWriter osw = new OutputStreamWriter(os, encoding);
    BufferedWriter bw = new BufferedWriter(osw);
    
    Cell[] row = null;
    for (int i = 0 ; i < s.getRows() ; i++)
    {
     row = s.getRow(i);
     if (row.length > 0)
     {
      bw.write(row[0].getContents());
      for (int j = 1; j < row.length; j++)
      {
       bw.write(user_delimiter);
       bw.write(row[j].getContents());
      }/*For loop closed*/
     }/*If closed*/         
     bw.newLine();
    }/*Row for loop closed*/
    bw.flush();
    bw.close();
    System.out.print("Output File " + (sheet+1) +  " is created: " + outputpath +"\output_"+ s.getName() +".txt" + "n" );
   }/*Worksheet for loop closed*/      
   System.out.print("Please open the output file(s) using notepad.");   
   
  }/*Try closed*/
  catch (Exception e)
  {
   System.err.println(e);
  }/*Catch closed*/
 }/*Main Closed*/
}/*Class closed*/

[ Read More ]

SPLIT HUGE FILES INTO SMALL TEXT FILES

This code snippet is used for automatic splitting of files conatining large content into smaller text files with specific number of records in each output file. The number of output files depends upon the number of lines to be splitted and the number of lines in the original file.

import java.io.*;
import java.util.Scanner;
public class split {
public static void main(String args[])
{
 try{
  // Reading file and getting no. of files to be generated
  String inputfile = "C:/test.txt"; //  Source File Name.
  double nol = 2000.0; //  No. of lines to be split and saved in each output file.
  File file = new File(inputfile);
  Scanner scanner = new Scanner(file);
  int count = 0;
  while (scanner.hasNextLine()) 
  {
   scanner.nextLine();
   count++;
  }
  System.out.println("Lines in the file: " + count);     // Displays no. of lines in the input file.

  double temp = (count/nol);
  int temp1=(int)temp;
  int nof=0;
  if(temp1==temp)
  {
   nof=temp1;
  }
  else
  {
   nof=temp1+1;
  }
  System.out.println("No. of files to be generated :"+nof); // Displays no. of files to be generated.
 
  //---------------------------------------------------------------------------------------------------------

  // Actual splitting of file into smaller files

  FileInputStream fstream = new FileInputStream(inputfile); DataInputStream in = new DataInputStream(fstream);

  BufferedReader br = new BufferedReader(new InputStreamReader(in)); String strLine;
 
  for (int j=1;j<=nof;j++)
  {
   FileWriter fstream1 = new FileWriter("C:/New Folder/File"+j+".txt");     // Destination File Location
   BufferedWriter out = new BufferedWriter(fstream1); 
   for (int i=1;i<=nol;i++)
   {
    strLine = br.readLine(); 
    if (strLine!= null)
    {
     out.write(strLine); 
     if(i!=nol)
     {
      out.newLine();
     }
    }
   }
   out.close();
  }

  in.close();
 }catch (Exception e)
 {
  System.err.println("Error: " + e.getMessage());
 }

}

} 

[ Read More ]

How to invoke an applet in JSP page

This Program contains step by step details from developing an applet to deploying into server.

It describes how to invoke an applet in JSP page.

A Java applet is a special kind of Java program that a browser enabled with Java technology can download from the internet and run. Applets are used to make the web site more dynamic than html pages.  

JSP Page Code snippet

<html>
<head>
<title>Using the Java Plugin</title>
</head>
<body>
<h4>Applet running in the plugin</h4>
<jsp:plugin type="applet" code="TimeApplet" codebase="." archive="JspApplet.jar"
            width="500"
            height="500"
            jreversion="1.7">
     <jsp:params>
          <jsp:param name="font" value="SansSerif" />
          <jsp:param name="fsize" value="12" />
          <jsp:param name="image" value="Menu.gif"/>
     </jsp:params>

     <jsp:fallback>
          <B>Unable to start plugin!</B>
     </jsp:fallback>

</jsp:plugin>


</body>
</html>

-------------

TimeApplet snippet


import java.applet.Applet;
import java.awt.Graphics;
import java.util.Date;

public class TimeApplet extends Applet implements Runnable {
 Thread timerThread;

 /* Applet Lifestyle Methods */
 public void start() {
  timerThread = new Thread(this, "Clock");
  timerThread.start();
 }
 public void stop() {
  if (timerThread == null)
   return;
  timerThread.stop();
  timerThread = null;
 }
 
 /* Runnable interface method */
 public void run() {
  while (timerThread != null) {
   repaint(); // request a redraw
   try {
    timerThread.sleep(1000);
   } catch (InterruptedException e){ /* do nothing*/ }
  }
 }

 /* AWT method */ 
 public void paint(Graphics g) {
  Date d = new Date();
  g.drawString(d.getHours() + ":" + d.getMinutes() + ":" + d.getSeconds(), 1, 10);
 }
}

[ Read More ]

Java code snippet to run unix command and shell script

This code snippet helps to run the command/shell script in unix environment and can be displayed in the Web environment.   

try {
        Process p = Runtime.getRuntime().exec("uname -a");
        // you can pass the system command or a script to exec command. here i used uname -a system command
        BufferedReader stdInput = new BufferedReader(new 
                InputStreamReader(p.getInputStream()));

        BufferedReader stdError = new BufferedReader(new 
                InputStreamReader(p.getErrorStream()));

        // read the output from the command
        String s="";
        
        while ((s = stdInput.readLine()) != null) {
            System.out.println("Std OUT: "+s);
        }
        
        while ((s = stdError.readLine()) != null) {
            System.out.println("Std ERROR : "+s);
        }
    
        
    } catch (IOException e) {
      
        e.printStackTrace();
    }

[ Read More ]

Send outlook meeting request using Java Mail API

This Program is useful to send meeting request to the users using Java mail API.We need to include mail.jar in the classpath.

import java.util.Properties;
import javax.activation.DataHandler;
import javax.mail.BodyPart; 
import javax.mail.Message; 
import javax.mail.MessagingException;
import javax.mail.Multipart; 
import javax.mail.Session; 
import javax.mail.Transport; 
import javax.mail.internet.InternetAddress; 
import javax.mail.internet.MimeBodyPart; 
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart; 
import javax.mail.util.ByteArrayDataSource; 
public class Email {

 public void send() throws Exception { 
  try {
   String host = "abc.com";//hostname of the mail server
   String from = "xx.xx.com"; //from internet address
   String to = "xx.xx.com"; //to internet address
   Properties prop = new Properties(); 
   prop.put("mail.host", host);   
   Session session = Session.getDefaultInstance(prop, null); 
   // Define message 
   MimeMessage message = new MimeMessage(session);
   message.addHeaderLine("method=REQUEST");
   message.addHeaderLine("charset=UTF-8"); 
   message.addHeaderLine("component=VEVENT"); 
   message.setFrom(new InternetAddress(from)); 
   message.addRecipient(Message.RecipientType.TO, new InternetAddress(to)); 
   message.setSubject("Meeting Request Using JavaMail"); 
   StringBuffer sb = new StringBuffer();  
   StringBuffer buffer = sb.append("BEGIN:VCALENDARn"+
     "PRODID:-//Microsoft Corporation//Outlook 9.0 MIMEDIR//ENn"+
     "VERSION:2.0n" +
     "METHOD:REQUESTn" + 
     "BEGIN:VEVENTn" +
     "ATTENDEE;ROLE=REQ-PARTICIPANT;RSVP=TRUE:MAILTO:xx.xx.comn" + 
     "ORGANIZER:MAILTO:xx.xx.comn" + 
     "DTSTART:20120703T134500Zn" + 
     "DTEND:20120703T140000Zn" + 
     "LOCATION:3N1 Conference roomn" +
     "TRANSP:OPAQUEn" +
     "SEQUENCE:0n" +
     "UID:040000008200E00074C5B7101A82E00800000000002FF466CE3AC5010000000000000000100n" +
     " 000004377FE5C37984842BF9440448399EB02n" +
     "DTSTAMP:20120703T120102Zn" + 
     "CATEGORIES:Meetingn" +
     "DESCRIPTION:This is a test meeting request.checking using JAVA .Please ingore itnn" +
     "SUMMARY:Test meeting requestn" + 
     "PRIORITY:1n" +
     "CLASS:PUBLICn" + 
     "BEGIN:VALARMn" + 
     "TRIGGER:PT1440Mn" +
     "ACTION:DISPLAYn" + 
     "DESCRIPTION:Remindern" +
     "END:VALARMn" +
     "END:VEVENTn" +
   "END:VCALENDAR");  // Create the message part
   BodyPart messageBodyPart = new MimeBodyPart(); 
   // Fill the message  
   messageBodyPart.setHeader("Content-Class", "urn:content-classes:calendarmessage");
   messageBodyPart.setHeader("Content-ID","calendar_message"); 
   messageBodyPart.setDataHandler(new DataHandler( new ByteArrayDataSource(buffer.toString(), "text/calendar")));//very important
   // Create a Multipart  
   Multipart multipart = new MimeMultipart();  
   // Add part one 
   multipart.addBodyPart(messageBodyPart);    
   // Put parts in message
   message.setContent(multipart);  
   // send message 
   Transport.send(message);
  } catch (MessagingException me) {
   me.printStackTrace(); 
  } catch (Exception ex) {
   ex.printStackTrace(); 
  } 
 } 


 /* @param args */ 
 public static void main(String[] args) { 
  try {
   Email email = new Email(); 
   email.send();
   System.out.println("meeting request is sent");
  } catch (Exception e) {
   e.printStackTrace(); 
  }  
 } 
}

[ Read More ]

Alphanumeric String Sorting using Java

Alphanumeric is a combination of alphabetic and numeric characters (sometimes shortened to alphameric).

In computing, the alphanumeric Strings can be seen very common to represent various codes etc. Sorting the alphanumeric strings can sometimes be a trouble by using regular sort techniques.

import java.util.Arrays;
import java.util.Comparator;
 
public class AlphanumericSorting implements Comparator {
    /**
     * The compare method that compares the alphanumeric strings
     */
    public int compare(Object firstObjToCompare, Object secondObjToCompare) {
        String firstString = firstObjToCompare.toString();
        String secondString = secondObjToCompare.toString();
 
        if (secondString == null || firstString == null) {
            return 0;
        }
 
        int lengthFirstStr = firstString.length();
        int lengthSecondStr = secondString.length();
 
        int index1 = 0;
        int index2 = 0;
 
        while (index1 < lengthFirstStr && index2 < lengthSecondStr) {
            char ch1 = firstString.charAt(index1);
            char ch2 = secondString.charAt(index2);
 
            char[] space1 = new char[lengthFirstStr];
            char[] space2 = new char[lengthSecondStr];
 
            int loc1 = 0;
            int loc2 = 0;
 
            do {
                space1[loc1++] = ch1;
                index1++;
 
                if (index1 < lengthFirstStr) {
                    ch1 = firstString.charAt(index1);
                } else {
                    break;
                }
            } while (Character.isDigit(ch1) == Character.isDigit(space1[0]));
 
            do {
                space2[loc2++] = ch2;
                index2++;
 
                if (index2 < lengthSecondStr) {
                    ch2 = secondString.charAt(index2);
                } else {
                    break;
                }
            } while (Character.isDigit(ch2) == Character.isDigit(space2[0]));
 
            String str1 = new String(space1);
            String str2 = new String(space2);
 
            int result;
 
            if (Character.isDigit(space1[0]) && Character.isDigit(space2[0])) {
                Integer firstNumberToCompare = new Integer(Integer
                        .parseInt(str1.trim()));
                Integer secondNumberToCompare = new Integer(Integer
                        .parseInt(str2.trim()));
                result = firstNumberToCompare.compareTo(secondNumberToCompare);
            } else {
                result = str1.compareTo(str2);
            }
 
            if (result != 0) {
                return result;
            }
        }
        return lengthFirstStr - lengthSecondStr;
    }
 
    /**
     * Testing the alphanumeric sorting
     */
    public static void main(String[] args) {
        String[] alphaNumericStringArray = new String[] { "NUM10071",
                "NUM9999", "9997", "9998", "9996", "9996F" };
 
        /*
         * Arrays.sort method can take an unsorted array and a comparator
         * to give a final sorted array.
         *
         * The sorting is done according to the comparator that we have
         * provided.
         */
        Arrays.sort(alphaNumericStringArray, new AlphanumericSorting());
 
        for (int i = 0; i < alphaNumericStringArray.length; i++) {
            System.out.println(alphaNumericStringArray[i]);
        }
 
    }
 
}

[ Read More ]

Calculating Age using Java

To check the age from the given year.

import java.util.GregorianCalendar;
import java.util.Calendar;

public class AgeCalculation {

 /**
  * Month Representations
  */
 static final int JAN = 0;
 static final int FEB = 1;
 static final int MAR = 2;
 static final int APR = 3;
 static final int MAY = 4;
 static final int JUN = 5;
 static final int JUL = 6;
 static final int AUG = 7;
 static final int SEP = 8;
 static final int OCT = 9;
 static final int NOV = 10;
 static final int DEC = 11;

 public static void main(String[] args) {
  System.out.println("Born In 1982-JUL-11. Current Age: "
    + calculateMyAge(1982, JUL, 11));
  System.out.println("Born In 1957-DEC-09. Current Age: "
    + calculateMyAge(1957, DEC, 9));
 }

 /**
  *
  * @param year --> Birth Year
  * @param month --> Birth Month
  * @param day --> Birth Day
  * @return --> Calculated Age
  */
 private static int calculateMyAge(int year, int month, int day) {
  Calendar birthCal = new GregorianCalendar(year, month, day);

  Calendar nowCal = new GregorianCalendar();

  int age = nowCal.get(Calendar.YEAR) - birthCal.get(Calendar.YEAR);

  boolean isMonthGreater = birthCal.get(Calendar.MONTH) >= nowCal
    .get(Calendar.MONTH);

  boolean isMonthSameButDayGreater = birthCal.get(Calendar.MONTH) == nowCal
    .get(Calendar.MONTH)
    && birthCal.get(Calendar.DAY_OF_MONTH) > nowCal
    .get(Calendar.DAY_OF_MONTH);

    if (isMonthGreater || isMonthSameButDayGreater) {
     age=age-1;
    }
    return age;
 }

}

[ Read More ]

Unicast Messaging in Java

Unicast messaging is used for all network processes in which a private or unique resource is requested.

import java.awt.*;
import java.awt.event.*;
import java.net.*;
import javax.swing.JFrame;

public class Unicast extends JFrame implements ActionListener{
 Label entermsgl,receivedmsgl,sentmsgl,toportl;
 TextField entermsg,toport;
 TextArea receivedmsg,sentmsg;
 Button send,exit;
 int myport;
 DatagramSocket ds;
 DatagramPacket dp;
 Unicast(){
  new InputDialog(this);
 }
 public void initialise(){
  setTitle("Unicast --Port:"+myport);
  setVisible(true);
  setSize(600,400);
  entermsgl=new Label("Enter Message:");
  receivedmsgl=new Label("Received Messages:");
  sentmsgl=new Label("Sent Messages:");
  toportl=new Label("To");
  toport=new TextField();
  entermsg=new TextField();
  receivedmsg=new TextArea();
  sentmsg=new TextArea();
  send=new Button("Send");
  exit=new Button("Exit");
  setLayout(null);
  add(entermsgl);
  entermsgl.setBounds(25,25,100,25);
  add(receivedmsgl);
  receivedmsgl.setBounds(25,70,150,25);
  add(sentmsgl);
  sentmsgl.setBounds(25,185,150,25);
  add(toportl);
  toportl.setBounds(350,25,25,25);
  add(toport);
  toport.setBounds(380,25,70,25);
  add(entermsg);
  entermsg.setBounds(130,25,200,25);
  add(receivedmsg);
  receivedmsg.setBounds(180,70,370,100);
  add(sentmsg);
  sentmsg.setBounds(180,185,370,100);
  add(send);
  send.setBounds(470,25,100,25);
  add(exit);
  exit.setBounds(250,300,100,25);
  try{
   ds=new DatagramSocket(myport);
  }catch(Exception e){
   System.out.println(e);
  }
  send.addActionListener(this);
  exit.addActionListener(this);
  new Receive();
 }
 class Receive extends Thread{
  Receive(){
   start();
  }
  public void run(){
   while(true){
    try{
     byte b[]=new byte[100];
     dp=new DatagramPacket(b,b.length);
     ds.receive(dp);
     receivedmsg.append("From "+dp.getPort()+": "+new String(dp.getData(),0,dp.getLength())+"n");
    }catch(Exception e){
     
    }
   }
   
  }
 }
 public void actionPerformed(ActionEvent ae){
  if(ae.getSource()==send){
   byte b[]=entermsg.getText().getBytes();
   try{
    int port=Integer.parseInt(toport.getText());
    if(port<1024 || port>65536){
      toport.setText("");
      return;
    }
    dp=new DatagramPacket(b,b.length,InetAddress.getLocalHost(),port);
    ds.send(dp);
    sentmsg.append("To "+port+": "+entermsg.getText()+"n");
   }catch(NumberFormatException nfe){
    toport.setText("");
   }catch(Exception e){
    
   }
  }
  else{
   System.exit(0);
  }
 }
 public static void main(String args[]){
  new Unicast();
 }

}


class InputDialog extends Dialog implements ActionListener{
 Button ok=new Button("Ok");
 Button cancel=new Button("Cancel");
 TextField tf=new TextField();
 Label l=new Label("Enter the port number:");
 Unicast parent;
 InputDialog(Unicast f){
  super(f,"Unicast - Port number");
  parent=f;
  setVisible(true);
  setSize(400,200);
  setLayout(null);
  add(l);
  l.setBounds(25,50,200,25);
  add(tf);
  tf.setBounds(225,50,100,25);
  add(ok);
  ok.setBounds(100,100,100,25);
  add(cancel);
  cancel.setBounds(220,100,100,25);
  ok.addActionListener(this);
  cancel.addActionListener(this);
 } 
 public void actionPerformed(ActionEvent ae){
  if(ae.getSource()==ok){
   try{
    int n=Integer.parseInt(tf.getText());
    if(n>1023 && n<65536){
     parent.myport=n;
     parent.initialise();
     this.dispose();
    }
    else{
     tf.setText("");
     tf.requestFocus();
    }
   }catch(NumberFormatException nfe){
    tf.setText("");
    tf.requestFocus();
   }
  }
  else if(ae.getSource()==cancel){
   System.exit(0);
  }
  
 }
}

[ Read More ]

Chat Client and Chat Server

Communication between the clients from Server

//Chat Server:-

import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;

public class ChatServer extends Frame implements ActionListener{
 Label listOfClients;
 List clientName;
 Button exit;
 Panel p1,p2;
 ServerSocket ss;
 Clients clients[];
 int n;
 boolean sendOk=true;
 boolean update=false;

 ChatServer(){
  super("ChatServer");
  setSize(400,300);
  setVisible(true);
  clientName=new List();
  listOfClients=new Label("List of Clients");
  exit=new Button("Exit");
  p1=new Panel();
  p2=new Panel();
  p1.setLayout(new FlowLayout());
  p2.setLayout(new FlowLayout());
  setLayout(new GridLayout(2,1));
  add(p1);
  add(p2);
  p1.add(listOfClients);
  p1.add(clientName);
  p2.add(exit);
  exit.addActionListener(this);
  try{
   ss=new ServerSocket(2500);
  }catch(Exception e){
  }
  clients=new Clients[50];
  n=0;
  new CheckNewClients().start();
  new UpdateClients().start();
  
 }
 public void actionPerformed(ActionEvent ae){
  System.exit(0);
 }
 public static void main(String args[]){
  new ChatServer();
 }
 class Clients extends Thread{
  Socket s;
  BufferedReader br;
  PrintWriter pw;
  String name="Client ";
  int i;
  boolean alive;
  public void run(){
   try{
    while(true){
     String temp=br.readLine();
     if(temp.equals("shutdown")){
      for(int x=0;x<clientName.getItemCount();x++)
       if(clientName.getItem(x).equals(name)){
        clientName.remove(x);
        break;
       }
      alive=false;
      update=true;
      break;
     }
     else if(temp.equals("msg")){
      String client=br.readLine(); 
      String msg=br.readLine();
      int x;
      for(x=0;x<n;x++)
       if(clients[x].name.equals(client))
        break;
      while(!sendOk);
      sendOk=false;
      clients[x].pw.println("msg");
      clients[x].pw.println(name+" : "+msg);
      sendOk=true;
     }
    }
   }catch(Exception e){ 
    for(int x=0;x<clientName.getItemCount();x++)
     if(clientName.getItem(x).equals(name)){
      clientName.remove(x);
      break;
     }
    alive=false;
    update=true;
   }
  }
 }
 class CheckNewClients extends Thread{
  public void run(){
   while(true){
    clients[n]=new Clients();
    try{
     clients[n].s=ss.accept(); 
     clients[n].br=new BufferedReader(new InputStreamReader(clients[n].s.getInputStream()));
     clients[n].pw=new PrintWriter(clients[n].s.getOutputStream(),true);
     clients[n].i=n;
     clients[n].name+=n;
     clients[n].alive=true;
     clientName.add(clients[n].name);
     clients[n].pw.println(clients[n].name);
     clients[n].start(); 
     update=true;
    }catch(Exception e){
     System.out.println(e);
    }
    n++;
   }
  }
 }
 class UpdateClients extends Thread{
  public void run(){
   while(true){
    while(!update);
    for(int i=0;i<n;i++){
     int count=clientName.getItemCount();
     if(!clients[i].alive)
      continue;
     try{
      while(!sendOk);
      sendOk=false;
      clients[i].pw.println("update");
      clients[i].pw.println(count-1);
      for(int x=0;x<count;x++)
       if(!clientName.getItem(x).equals(clients[i].name))
        clients[i].pw.println(clientName.getItem(x));
      sendOk=true;
     }catch(Exception e){
      System.out.println(e);
     }
    }
    update=false;
   }
  }
 }
}


//Chat Client:-

import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;

public class ChatClient extends Frame implements ActionListener{
 Label enterMessage,to,receivedMessages,sentMessages;
 TextField enterMessaget;
 TextArea receivedMessagest,sentMessagest;
 Button send,exit;
 Choice clientName;
 Panel p1,p2,p3,p4;
 Socket s;
 PrintWriter pw;
 BufferedReader br;

 ChatClient(){
  super("ChatClient");
  setVisible(true);
  setSize(500,300);
  enterMessage=new Label("Enter Message");
  to=new Label("To");
  receivedMessages=new Label("Received Messages");
  sentMessages=new Label("Sent Messages");
  enterMessaget=new TextField();
  receivedMessagest=new TextArea("",20,5,TextArea.SCROLLBARS_VERTICAL_ONLY);
  sentMessagest=new TextArea();
  clientName=new Choice();
  send=new Button("Send");
  exit=new Button("Exit");
  p1=new Panel();
  p2=new Panel();
  p3=new Panel();
  p4=new Panel();
  setLayout(new GridLayout(4,1));
  p1.setLayout(null);
  p2.setLayout(new GridLayout(1,2));
  p3.setLayout(new GridLayout(1,2));
  p4.setLayout(new FlowLayout());
  p1.add(enterMessage);
  enterMessage.setBounds(10,10,100,25);
  p1.add(enterMessaget);
  enterMessaget.setBounds(110,10,100,25);
  p1.add(to);
  to.setBounds(220,10,30,25);
  p1.add(clientName);
  clientName.setBounds(260,10,100,25);
  p1.add(send);
  send.setBounds(370,10,100,25);
  p2.add(receivedMessages);
  p2.add(receivedMessagest);
  p3.add(sentMessages);
  p3.add(sentMessagest);
  p4.add(exit);
  add(p1);
  add(p2);
  add(p3);
  add(p4);
  exit.addActionListener(this); 
  send.addActionListener(this);
  try{
   s=new Socket("localhost",2500);
   br=new BufferedReader(new InputStreamReader(s.getInputStream()));
   pw=new PrintWriter(s.getOutputStream(),true);
   setTitle(br.readLine());
  }catch(Exception e){
   System.out.println("Exception: Problem establishing connectionn"+e);
  }
  new ReceiveMsg().start();
 }
 public static void main(String args[]){
  new ChatClient();
 }
 public void actionPerformed(ActionEvent ae){
  if(ae.getSource()==send){
   try{
    pw.println("msg");
    String client=clientName.getSelectedItem();
    String msg=enterMessaget.getText();
    pw.println(client);
    pw.println(msg);
    sentMessagest.append(client+" : "+msg+"n");
   }catch(Exception e){
   }
   
  }
  else if(ae.getSource()==exit){
   try{
    pw.println("shutdown");
   }catch(Exception e){
   }
   System.exit(0);
  }
 }
 class ReceiveMsg extends Thread{
  public void run(){
   while(true){
    try{
     String temp=br.readLine();
     if(temp.equals("update")){
      receiveUpdate();     
     }
     else if(temp.equals("msg")){
      receiveMsg();
     }
    }catch(Exception e){
    }
   }    
  }
  public void receiveMsg(){
   try{
    receivedMessagest.append(br.readLine()+"n");
   }catch(Exception e){
   }
  }
  public void receiveUpdate(){
   try{
    int n=Integer.parseInt(br.readLine());
    clientName.removeAll();
    for(int i=0;i<n;i++)
     clientName.add(br.readLine());      
   }catch(Exception e){
   }
  }
 }
 class sendUpdate extends Thread{
  public void run(){
   while(true){
    pw.println("alive");
    try{
     sleep(10000);
    }catch(Exception e){
    }
   }
  }
 }
}

[ Read More ]

MultiCast Messaging in Java

Sending the file or message to a set of clients or group of clients

import java.awt.*;
import java.awt.event.*;
import java.net.*;
import javax.swing.JFrame;

public class Multicast extends JFrame implements ActionListener,Runnable{
 Label entermsgl,receivedmsgl,sentmsgl;
 TextField entermsg;
 TextArea receivedmsg,sentmsg;
 Button Multicast,exit;
 int myport;
 MulticastSocket ms_send,ms_receive;
 DatagramPacket dp;
 InetAddress address;
 Thread t;
 Multicast(){
  initialise();
 }
 public void initialise(){
  setTitle("Multicast ");
  setVisible(true);
  setSize(600,400);
  entermsgl=new Label("Enter Message:");
  receivedmsgl=new Label("Received Messages:");
  sentmsgl=new Label("Sent Messages:");
  entermsg=new TextField();
  receivedmsg=new TextArea();
  sentmsg=new TextArea();
  Multicast=new Button("Multicast");
  exit=new Button("Exit");
  setLayout(null);
  add(entermsgl);
  entermsgl.setBounds(25,25,100,25);
  add(receivedmsgl);
  receivedmsgl.setBounds(25,70,150,25);
  add(sentmsgl);
  sentmsgl.setBounds(25,185,150,25);
  add(entermsg);
  entermsg.setBounds(130,25,200,25);
  add(receivedmsg);
  receivedmsg.setBounds(180,70,370,100);
  add(sentmsg);
  sentmsg.setBounds(180,185,370,100);
  add(Multicast);
  Multicast.setBounds(470,25,100,25);
  add(exit);
  exit.setBounds(250,300,100,25);
  try{
   address=InetAddress.getByName("230.150.150.15");
   ms_send=new MulticastSocket();
   ms_receive=new MulticastSocket(2001);
   ms_receive.joinGroup(address);
  }catch(Exception e){
   System.out.println(e);
  }
  Multicast.addActionListener(this);
  exit.addActionListener(this);
  t=new Thread(this);
  t.start();
 }
 //class Receive extends Thread{
 // Receive(){
  // start();
  //}
  public void run(){
   while(true){
    System.out.println("1");
    try{
     DatagramPacket dp1;
     byte b[]=new byte[100];
     System.out.println("2");
     dp1=new DatagramPacket(b,b.length);
     ms_receive.receive(dp1);
     System.out.println("3");
     receivedmsg.append("From "+dp1.getAddress()+" "+dp1.getPort()+": "+new String(dp1.getData(),0,dp1.getLength())+"\n");
     repaint();
    }catch(Exception e){
     System.out.println(e);
    }
   }
   
  }
 //}
 public void actionPerformed(ActionEvent ae){
  if(ae.getSource()==Multicast){
   byte b[]=entermsg.getText().getBytes();
   try{
    dp=new DatagramPacket(b,b.length,address,2001);
    ms_send.send(dp,(byte)1);
    sentmsg.append(ms_send.getLocalAddress()+" port:"+ms_send.getLocalPort()+": "+entermsg.getText()+"\n");
   }catch(NumberFormatException nfe){
   }catch(Exception e){
    System.out.println(e);
   }
  }
  else{
   System.exit(0);
  }
 }
 public static void main(String args[]){
  new Multicast();
 }

}

[ Read More ]

File checksum in Java

If want to check two files and calculate their hashcode to make sure files are different or same. This function will caluclate the file checksum to compare two files. It will take file as an input.

//To generate a file checksum value with "SHA-1" mechanism 
import java.io.FileInputStream;
import java.security.MessageDigest;
 
public class TestCheckSum {
 
  public static void main(String args[]) throws Exception {
 
    String datafile = "c:\INSTLOG.TXT";
 
    MessageDigest md = MessageDigest.getInstance("SHA1");
    FileInputStream fis = new FileInputStream(datafile);
    byte[] dataBytes = new byte[1024];
 
    int nread = 0; 
 
    while ((nread = fis.read(dataBytes)) != -1) {
      md.update(dataBytes, 0, nread);
    };
 
    byte[] mdbytes = md.digest();
 
    //convert the byte to hex format
    StringBuffer sb = new StringBuffer("");
    for (int i = 0; i < mdbytes.length; i++) {
     sb.append(Integer.toString((mdbytes[i] & 0xff) + 0x100, 16).substring(1));
    }
 
    System.out.println("Digest(in hex format):: " + sb.toString());
 
  }
}

[ Read More ]

conversion of HTML data to TEXT

The contents from HTML page is extracted and diplayed in text format. The HTML page is given as input where the java code removes the HTML tags and the text is extracted.

import java.io.File;
import java.io.FileInputStream;

import java.io.Reader;
import java.io.StringReader;

import java.io.IOException;

/**
 * Convert text/html into text/plain
 */

public class HTML2Text
{
 boolean body_found = false;
 boolean in_body = false;
 boolean center = false;
 boolean pre = false;
 String href = "";

 public String convert(String source) throws Exception
 {
  StringBuffer result = new StringBuffer();
  StringBuffer result2 = new StringBuffer();
  StringReader input = new StringReader(source);

  try
  {
   String text = null;
   int c = input.read();

   while (c != -1) // Convert until EOF
   {
    text = "";
    if (c == '<') // It's a tag!!
    {
     String CurrentTag = getTag(input); // Get the rest of the tag
     text = convertTag(CurrentTag);
    }
    else if (c == '&')
    {
     String specialchar = getSpecial(input);
     if (specialchar.equals("lt;") || specialchar.equals("#60"))
      text = "<";
     else if (specialchar.equals("gt;") || specialchar.equals("#62"))
      text = ">";
     else if (specialchar.equals("amp;") || specialchar.equals("#38"))
      text = "&";
     else if (specialchar.equals("nbsp;"))
      text = " ";
     else if (specialchar.equals("quot;") || specialchar.equals("#34"))
      text = """;
      else if (specialchar.equals("copy;") || specialchar.equals("#169"))
       text = "[Copyright]";
      else if (specialchar.equals("reg;") || specialchar.equals("#174"))
       text = "[Registered]";
      else if (specialchar.equals("trade;") || specialchar.equals("#153"))
       text = "[Trademark]";
      else
       text = "&" + specialchar;
    }
    else if (!pre && Character.isWhitespace((char)c))
    {
     StringBuffer s = in_body ? result : result2;
     if (s.length() > 0 && Character.isWhitespace(s.charAt(s.length()-1)))
      text = "";
     else text = " ";
    }
    else
    {
     text = "" + (char)c;
    }

    StringBuffer s = in_body ? result : result2;
    s.append(text);

    c = input.read();
   }
  }
  catch (Exception e)
  {
   input.close();
   throw e;
  }

  StringBuffer s = body_found ? result : result2;
  return s.toString().trim();
 }

 String getTag(Reader r) throws IOException
 {
  StringBuffer result = new StringBuffer();
  int level = 1;

  result.append('<');
  while (level > 0)
  {
   int c = r.read();
   if (c == -1) break; // EOF
   result.append((char)c);
   if (c == '<') level++; else if (c == '>') level--;
  }

  return result.toString();
 }

 String getSpecial(Reader r) throws IOException
 {
  StringBuffer result = new StringBuffer();
  r.mark(1);//Mark the present position in the stream
  int c = r.read();

  while (Character.isLetter((char)c))
  {
   result.append((char)c);
   r.mark(1);
   c = r.read();
  }

  if (c == ';') result.append(';');
  else r.reset();

  return result.toString();
 }

 boolean isTag(String s1, String s2)
 {
  s1 = s1.toLowerCase();
  String t1 = "<" + s2.toLowerCase() + ">";
  String t2 = "<" + s2.toLowerCase() + " ";

  return s1.startsWith(t1) || s1.startsWith(t2);
 }

 String convertTag(String t) throws IOException
 {
  String result = "";

  if (isTag(t,"body"))
  { in_body = true; body_found = true; }
  else if (isTag(t,"/body"))
  { in_body = false; result = "
  "; }
  else if (isTag(t,"center"))
  { result = "
  "; center = true; }
  else if (isTag(t,"/center"))
  { result = "
  "; center = false; }
  else if (isTag(t,"pre"))
  { result = "
  "; pre = true; }
  else if (isTag(t,"/pre"))
  { result = "
  "; pre = false; }
  else if (isTag(t,"p"))
   result = "

   ";
   else if (isTag(t,"br"))
    result = "
    ";
    else if (isTag(t,"h1") || isTag(t,"h2") || 
      isTag(t,"h3") ||isTag(t,"h4") || isTag(t,"h5") || isTag(t,"h6") || isTag(t,"h7"))
     result = "
     ";
     else if (isTag(t,"/h1") || isTag(t,"/h2") || 
       isTag(t,"/h3") ||isTag(t,"/h4") || isTag(t,"/h5") || isTag(t,"/h6") || isTag(t,"/h7"))
      result = "
      ";
      else if (isTag(t,"/dl"))
       result = "
       ";
       else if (isTag(t,"dd"))
        result = "
        * ";
        else if (isTag(t,"dt"))
         result = "      ";
        else if (isTag(t,"li"))
         result = "
         * ";
         else if (isTag(t,"/ul"))
          result = "
          ";
          else if (isTag(t,"/ol"))
           result = "
           ";
           else if (isTag(t,"hr"))
            result = "_________________________________________

            ";
            else if (isTag(t,"table"))
             result = "
             ";
             else if (isTag(t,"/table"))
              result = "
              ";
              else if (isTag(t,"form"))
               result = "
               ";
               else if (isTag(t,"/form"))
                result = "
                ";
                else if (isTag(t,"b"))
                 result = "*";
                else if (isTag(t,"/b"))
                 result = "*";
                else if (isTag(t,"i"))
                 result = """;
                 else if (isTag(t,"/i"))
                  result = """;
                  else if (isTag(t,"img"))
                  {
                   int idx = t.indexOf("alt="");
                     if (idx != -1)
                     {
                      idx += 5;
                      int idx2 = t.indexOf(""",idx);
                        result = t.substring(idx,idx2);
                     }
                  }
                  else if (isTag(t,"a"))
                  {
                   int idx = t.indexOf("href="");
                     if (idx != -1)
                     {
                      idx += 6;
                      int idx2 = t.indexOf(""",idx);
                        href = t.substring(idx,idx2);
                     }
                     else
                     {
                      href = "";
                     }
                  }
                  else if (isTag(t,"/a"))
                  {
                   if (href.length() > 0)
                   {
                    result = " [ " + href + " ]";
                    href = "";
                   }
                  }

  return result;
  }

  public static void main(String argv[]) throws Exception
  {
   FileInputStream fis = null;
   String s = null;

   try
   {
    File file;
    if (argv[0] != null) file = new File(argv[0]);
    else file = new File("html_test_file.html");
    fis = new FileInputStream(file);
    byte buf[] = new byte[fis.available()];
    //bytes that can be read from this file input stream without blocking

    fis.read(buf);
    fis.close();
    fis = null;
    s = new String(buf);
    HTML2Text h = new HTML2Text();
    System.out.println(h.convert(s));
   }
   catch (Exception e)
   {
    if (fis != null) fis.close();
    throw e;
   }
  }
  }

[ Read More ]

Compare two files using Java

The program will prompt for 2 file names(.txt) that are to be compared. Given the file names, this program will compare the two files.

If any difference is there, it will print the differences and no. of differences in command prompt. 

If no difference is there, it will print

"files are equal".

import java.io.*;
import java.util.*;

//defining class

public class myfilereader
{
//defining main function
 public static void main (String[] args) throws java.io.IOException
    {
  //Getting the name of the files to be compared.
  BufferedReader br2 = new BufferedReader (new
InputStreamReader(System.in));
  System.out.println("Enter 1st File name:");
    String str = br2.readLine();
    System.out.println("Enter 2nd File name:");
    String str1 = br2.readLine();

  String s1="";
    String s2="",s3="",s4="";
    String y="",z="";

        //Reading the contents of the files
   BufferedReader br = new BufferedReader (new FileReader (str));
    BufferedReader br1 = new BufferedReader (new FileReader (str1));

   while((z=br1.readLine())!=null)
    s3+=z;

  while((y=br.readLine())!=null)
     s1+=y;

  System.out.println ();

        //String tokenizing
    int numTokens = 0;
    StringTokenizer st = new StringTokenizer (s1);
    String[] a = new String[10000];
    for(int l=0;l<10000;l++)
      {a[l]="";}
    int i=0;
    while (st.hasMoreTokens())
      {
        s2 = st.nextToken();
          a[i]=s2;
   i++;
            numTokens++;
      }

      int numTokens1 = 0;
     StringTokenizer st1 = new StringTokenizer (s3);
     String[] b = new String[10000];
     for(int k=0;k<10000;k++)
      {b[k]="";}
     int j=0;
     while (st1.hasMoreTokens())
       {
        s4 = st1.nextToken();
        b[j]=s4;
        j++;
        numTokens1++;
       }

//comparing the contents of the files and printing the differences, if any.
  int x=0;
      for(int m=0;m<a.length;m++)
      {
   if(a[m].equals(b[m])){}
    else
    {
     x++;
  System.out.println(a[m] + " -- " +b[m]);
  System.out.println();}
      }
 System.out.println("No. of differences : " + x);
 if(x>0){System.out.println("Files are not equal");}
 else{System.out.println("Files are equal. No difference found");}

 }
}

[ Read More ]

Jasper report as pdf

prints the report in pdf format.

//import it in the java file

import net.sf.jasperreports.engine.JasperExportManager;
// a function ehich calls the jasper to generate the report
private String generatePldbbyCC(ParameterReportCriteria prcObject, Map reportMap) throws Exception {
 JasperPrint jasperPrint = null;
 JRFileVirtualizer virtualizer = null;
 String destFileLoc = null;
 File sourceFile = null;
 File destFile = null;
 ESpecDAOController control = new ESpecDAOController();
 // puts the parameters to jasper.
 parameters.put(Constants.COMPETITIVE_CATEGORIES, prcObject.getSelectedCompCategs()); 
 parameters.put("REPORT_CONNECTION", control.getMasterConnection());
 parameters.put(EspecConstants.CURR_TIME, "Exported: " + new SimpleDateFormat("M/d/yyyy 'at' hh:mm:ss a").format(DateUtil.getCurrentDateTime()));

 PropertiesVO templatePath = setJasperpath();

 virtualizer = new JRFileVirtualizer(1, templatePath.getValue());

 parameters.put(SUBREPORT_DIR, templatePath.getValue());

 parameters.put(JRParameter.REPORT_VIRTUALIZER, virtualizer);

 try {

  jasperPrint = JasperFillManager.fillReport(templatePath.getValue() + "/sample.jasper", parameters, control.getMasterConnection());

 } else {
  //get the file with extension as pdf
  destFile = new File(templatePath.getValue(), jasperPrint.getName() + "_" + prcObject.getProcessId() + ".pdf");

 } 

 destFileLoc = destFile.toString();
 //exports the report as pdf.
 JasperExportManager.exportReportToPdfFile(jasperPrint,destFileLoc);

[ Read More ]

Finding the difference between two images using their samples

Helps in finding the difference between two images by obtaining their samples and comparing them. The number of bands assosiated with each image is also compared, along with their width and height.

File file1 = new File("C:\Documents and Settings\515956\Desktop\Raj_image.jpg"); 
File file2 = new File("C:\Documents and Settings\515956\Desktop\Local_image.jpg");  
BufferedImage image1 = ImageIO.read(file1); 
BufferedImage image2 = ImageIO.read(file2);

Raster r1 = image1.getData();
Raster r2 = image2.getData(); 
boolean ret; // Stores result. 
// Check image sizes and number of bands. If there are different
// then no need to compare images as they are definitely not equal. 

System.out.println("image1 band"+r1.getNumBands()+"  image2 band"+r2.getNumBands()+"  image1 width"+r1.getWidth()+"  image2 width"+ r2.getWidth()+"  image1 height"+ r1.getHeight()+"  image2 height"+r2.getHeight()); 

if (r1.getNumBands() != r2.getNumBands() ||   r1.getWidth() != r2.getWidth() ||   r1.getHeight() != r2.getHeight()) {  
 ret = false;
 System.out.println("Primary comparison failure");

} 

else {  
 // #Bands and image bounds match so compare each sample in turn. 
 ret = true;   
 search:   
  for (int i=0; i<r1.getNumBands(); ++i) { 
   for (int x=0; x<r1.getWidth(); ++x) {    
    for (int y=0; y<r1.getHeight(); ++y) {  


     if (r1.getSample(x, y, i) != r2.getSample(x, y, i)) {     
      // At least one sample differs so result is false; 
      ret = false; 
      System.out.println("sample difference");
      // Use labeled break to terminate all loops.
      break
      search;   
     }   
    }    
   }   
  }   

}
System.out.println(ret);

[ Read More ]

Preventing CRLF injection

This code will encode your data if a user tries to attack your application through CRLF injection

String s=Arrays.toString(object);
if(s.contains("/") || s.contains(">")||s.contains("<")||s.contains("?") ||s.contains("&") ||s.contains(""))
{
 String validobject=URLEncoder.encode(s);
 System.out.println("the encoded data is"+validobject);
}
else
{
 System.out.println("the non-encoded data is"+object);
}

[ Read More ]

Send a mail from SMTP server using Java Mail

This code allows the user to login to his/her mail account to send a mail to another recepient.First the code needs to be configured by entering the Server details and user credentials .This code authenticates the user and creates a session then a MimeMessage Object is created where the subject and content of the mail is set.

public class SmtpMail{
 public static void main(String[] args) 
 {
  Properties props = new Properties();
  props.put("mail.smtp.auth", "true");
  props.put("mail.smtp.starttls.enable", "true");
  props.put("mail.smtp.host", "smtp.gmail.com");
  props.put("mail.smtp.port", "587");
  final String username = "Username@gmail.com";
  final String password = "Password";
  Session session = Session.getInstance(props,
new javax.mail.Authenticator() {
 protected PasswordAuthentication getPasswordAuthentication() {
   return new PasswordAuthentication(username, password);
  }
  });
try {
   Message message = new MimeMessage(session);
   message.setRecipients(Message.RecipientType.TO,
    InternetAddress.parse("toEmailAddress@yahoo.com"));
   System.out.println(session.toString());
   message.setSubject("JavaMail Subject");
   message.setText("Dear Recepient,"
    + "\n\n This is a Test Mail");
   System.out.println(session.toString());
   Transport.send(message);
   System.out.println("Done");
 
  } catch (MessagingException e) {
   throw new RuntimeException(e);
  }
 }
}

[ Read More ]

Creating JSON using Java

This is used to create JSON objects using Java

import org.json.JSONObject;
//Creating JSON object
JSONObject json = new JSONObject();
//Put tag name and value to the object
json.put("city", "Mumbai");
json.put("country", "India");

String output = json.toString();

[ Read More ]

Getting Timezone based Timestamp

It is used to find the Timestamp based on the given Timezone

//Creating format based on the need
SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
//Set the Timezone 
dateFormat.setTimeZone(clientTimeZone);
String clientTime = dateFormat.format(date);
Date date2 = new Date(clientTime);
//
System.out.println(date2);

[ Read More ]

Determining MIME Type of the File

This is used to determine the MIME type of the file

try {
//Type is used to find the type of the file. It can be "text/plain", "text/xml" ,etc
    String type = Files.probeContentType(filename);
    if (type == null) {
        System.err.format("'%s' has an" + " unknown filetype.%n", filename);
    } else if (!type.equals("text/plain") {
        System.err.format("'%s' is not" + " a plain text file.%n", filename);
        continue;
    }
} catch (IOException x) {
    System.err.println(x);
}

[ Read More ]

Taking File name from Absolute Path

Exact file name extraction is required many times, when dealing with files

public static String extractFileName(String absoluteFileName) {  

 if (!isNullOrEmpty(absoluteFileName)) {  
  //File with the absolute path
  absoluteFileName = absoluteFileName.substring(absoluteFileName  
    .lastIndexOf(File.separatorChar) + 1, absoluteFileName.lastIndexOf("."));  
  //File name extracted the absolute path
 }  
 return absoluteFileName;  
}  

[ Read More ]

Convertion of CSV to Table

It converts the comma seperated value file to a table in database.

/*
 * This program used to convert data from CSV file to TABLE

 */

import java.sql.*;
import java.io.*;
public class ConvertCSVtoTABLE {
    
    public void covertCsvtotable(String file)
    {
        Connection conn;
        conn=null;
        ResultSet rs;
        Statement stmt;
        String Query="";
        try
        {
            /*****This program connect with MS-ACCESS DATABASE******/
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            conn=DriverManager.getConnection("jdbc:odbc:DB");
            stmt = conn.createStatement();
             /******************************************************/
      
            
            int noofcolumn=1,b,bprev,i;
            String text1="'";
            String filename=file;
            FileReader fin=new FileReader(filename);
            BufferedReader bf=new BufferedReader(fin);
            b=bf.read();
            while(b!=-1){
                bprev=b;
                if(b==44)
                {
                    text1=text1+"'";
                    noofcolumn=noofcolumn+1;
                }
                if(b==10)
                {
                     text1=text1+"'";
                     Query="insert into temptable(";
                     for(i=1;i<noofcolumn;i++)
                         Query=Query+"col"+i+",";
                     Query=Query+"col"+i;
                     Query=Query+") values("+text1+")";
                     stmt.executeUpdate(Query);
                     text1="'";
                     noofcolumn=1;
               }
               if(b!=34 && b!=10)
                {
                     text1=text1+(char)b;
                }
               b=bf.read();
               if(bprev==44)
                     text1=text1+"'";
             }
            
            fin.close();
            bf.close();
            conn.close();
            System.out.println("Data Transferred from CSV to TempTable Successfully :)");
         }
  
        catch(Exception E)
        {
             System.out.println(E);
        }        
    }
    
  public static void main(String[] args) 
    {
          ConvertCSVtoTABLE C=new ConvertCSVtoTABLE();
          C.covertCsvtotable("C:\Users\Raj\input.csv");
        
    }
}

[ Read More ]

Array Resize in Java

Creates a new array and reallocate an array with a new size, and copies the contents of the old array to the new array.

//  oldArray  is  the old array, to be reallocated.
// newSize is  the new array size.
// return   type is a new array with the same contents.

public Object resizeArray (Object oldArray, int newSize) {
   int oldSize = java.lang.reflect.Array.getLength(oldArray);
   Class elementType = oldArray.getClass().getComponentType();
   Object newArray = java.lang.reflect.Array.newInstance(
         elementType,newSize);
   int preserveLength = Math.min(oldSize,newSize);
   if (preserveLength > 0)
      System.arraycopy (oldArray,0,newArray,0,preserveLength);
   return newArray;
}

[ Read More ]

JDBC Connection with Oracle

There is a property file in which database name,user name,user password is saved.With the use of this file JDBC connection can be stablished with oracle.

//load a file that has all the information of database,user name,user password.
//It will throw ClassNotFoundException if class is not found
//If any exception due to database is occured then it  throws SQLException
String driverClass = "oracle.jdbc.driver.OracleDriver";
Connection con;
public void init(FileInputStream fs) throws ClassNotFoundException, SQLException, FileNotFoundException, IOException
    {
        Properties props = new Properties();
        props.load(fs);
        String url = props.getProperty("db.url");
        String userName = props.getProperty("db.user");
        String password = props.getProperty("db.password");
        Class.forName(driverClass);
 
        con=DriverManager.getConnection(url, userName, password);
    }

[ Read More ]

Searching for a key in Log Files by connecting to Servers via SSH

This code helps us to search for the particular key in the log files by connecting to that servers and getting the entries that matches our search key. This can connect to different servers and fetch the results based on our confiuguration.

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.InputStreamReader;
import java.io.Writer;

import ch.ethz.ssh2.Connection;
import ch.ethz.ssh2.Session;
import ch.ethz.ssh2.StreamGobbler;

/*
*
*Dependency : This java code is dependent on the below jar file which can be downloaded
*Jar Name : ganymed-ssh2-build210.jar
*
*/

public class FilePreviewer {

 private File outputFile;
 private Writer outputStream;
 public static String newline = System.getProperty("line.separator");
 
 public FilePreviewer()
 {
  
 }
 
 public FilePreviewer(String user, String pass)
 {
  
  String ipAd[]={"IP1","IP2"};
  int x=1, numOfServers=x+1;
  String keyText="searchKey"; //search key
  while(x<numOfServers) //incase if we want to search in more than one server in a loop
  {
   try
   {
    Connection connection = new Connection(ipAd[x]);
    connection.setTCPNoDelay(true);
    connection.connect();
    Authentication a=new Authentication(pass);
    System.out.println("Connection Established: "+ipAd[x]);
    outputFile=new File("output_"+x+".txt");//Output File name
    boolean flag=false;
    if(connection.isAuthMethodAvailable(user, "password"))
     flag = connection.authenticateWithPassword(user,pass);
    if(!flag)
    {
     flag = connection.authenticateWithKeyboardInteractive(user, a);
    }
    if (flag == true)
    {
     Session session = connection.openSession();
     String s3 = "grep -i '"+keyText+"' /home/userId/folder/filename.log"; //Configure the search command to point to any file. 
     session.execCommand(s3);
     StreamGobbler streamgobbler = new StreamGobbler(session.getStdout());
     BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(streamgobbler));
     outputStream = new BufferedWriter(new FileWriter(outputFile));
     String cmdOut="";
     int count=0;
     do 
     {
      cmdOut = bufferedreader.readLine();
      if(cmdOut==null)
       break;
      System.out.println(cmdOut);
      outputStream.write(cmdOut+newline);
      count++;
     } while (true);
     outputStream.close();
     session.close();
     
     connection.close();
     if (count==0)
     {
      System.out.println("KeyText not found");
     }
     else
     {
      System.out.println("Found: "+count);
      count=0;
     }
    }
    else
    {
     System.out.println(" Authentication Failed");
    }
   }
   catch(Exception e)
   {
    System.out.println("n"+e.toString());
   }
   x=x+6;
  }
 }
 
 public static void main(String[] args) 
 {
  new FilePreviewer("user","pwd"); //user name and password
 }

}

//Code that takes care of KeyBoard Interactive Authentication

class Authentication implements ch.ethz.ssh2.InteractiveCallback
{
 int promptCount;
 String pwd;

 public Authentication(String password)
 {
  promptCount = 0;
  pwd = password;
 }

 public String[] replyToChallenge(String name, String instruction, int numPrompts, String prompt[], boolean echo[]) throws Exception
 {
  String result[] = new String[numPrompts];
  for(int i = 0; i < numPrompts; i++)
  {
   if(prompt[i].contains("Password:"))
   {
    result[i] = pwd;
    promptCount++;
   }
  }
  return result;
 }
}

[ Read More ]