3 java questions: debugging, templating and Swing app for Texts cleansing

// __ how do you debug debug:
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 Exception in thread "main" java.lang.OutOfMemoryError: Java heap
space
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 kinds of errors?
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// __ How can you make this method taking in an array on ints and
enlarging it, make the same thing for long[]('s), byte[]('s) in fact
any possible array.
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// __ (((iAr != null) && ((iArL = iAr.length) > 0)) || (iNwL > 0))
 public int[] _enlargeIntArr(int[] iAr, int iNwL) throws
InputContextException{
  boolean Is = false;
  int[] iNwAr = null;
  int iArL;
// __
  if((iAr != null) && ((iArL = iAr.length) > 0)){
   if(iNwL > iArL){
    iNwAr = new int[iNwL];
    System.arraycopy(iAr, 0 , iNwAr, 0, iNwL);
    iAr = null;
    System.gc();
   }// (iNwL > iArL)
   else{
    String aX = "// __ New Length must be greater than previous one.
iNwL: |" + iNwL + "|, iArL: |" + iArL + "|";
    throw new InputContextException(aX);
   }
  }// ((iAr != null) && ((iArL = iAr.length) > 0))
  else if(iNwL > 0){ iNwAr = new int[iNwL]; }
  else{
   String aX = "// __ New Length must be greater than 0. iNwL: |" +
iNwL + "|";
   throw new InputContextException(aX);
  }
// __
  return(iNwAr);
 }
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// __ Do you know of any swing application to compare two text files,
partially programatically, partially by eyeballing them?
 The j app. should syncronize teh scrolling of both texts to that the
same section would be visible even if you scroll one of them
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 thanks
 lbrtchx