Generic Array To String Function

public static String arrayToString(Object array) {    
 if (array == null) {
  return "[NULL]"; 
 }
 Object obj = null;   
 if (array instanceof Hashtable) {
  array = ((Hashtable)array).entrySet().toArray(); 
 }          else if (array instanceof HashSet) {
  array = ((HashSet)array).toArray(); 
 }      else if (array instanceof Collection) {
  array = ((Collection)array).toArray(); 
 }         

 int length = Array.getLength(array);  
 int lastItem = length - 1;  
 StringBuffer sb = new StringBuffer("[");  

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

  obj = Array.get(array, i);      
  if (obj != null) { 

   sb.append(obj); 
  } else { 
   sb.append("[NULL]"); 
  }    
  if (i < lastItem) { 
   sb.append(", ");
  }    

 }    

 sb.append("]");    
 return sb.toString(); 
} 
}