Programming Homework Help

Hello all, i m getting error while writing object to a file. for smaller size object no error it works fine but larger size object it writes but later getting error. can anybody help in this regard?

private void mistreeActionPerformed(java.awt.event.ActionEvent evt) {   
// TODO add your handling code here:
//int ret = jc.showOpenDialog(this);
  //  if(ret == JFileChooser.APPROVE_OPTION)
  //  {
  try
  {
  File f = jc.getSelectedFile();
  if(f != null){
  String fname = f.getAbsolutePath();
  datasetfile.setText(fname);   
  String database = fname;
  // tree = new MISTree();
  //if(fname != null)
  misTreeConstruction(database, output, Misout,MISfile);
  }
  else
  JOptionPane.showMessageDialog(null, “Plz select a file first”);
     //tree.backtotrans();
  //printStats();
   
  }catch(Exception ex) {
  JOptionPane.showMessageDialog(null, “Error in input file Plz select trasanction file”);
  // ex.printStackTrace();
  return;
  }
  // }
   
}  

public void misTreeConstruction(String input, String output, String Misout,String MISIn)
       throws FileNotFoundException, IOException {
     // record start time
     startTimestamp = System.currentTimeMillis();
     
     transactionCount = 0;
     // (1) PREPROCESSING: Perform an initial database scan to determine the
     // MIS of each item
     
     // This map is used to count the support of each item
     // Key: item  Value: support
mapSupport = new HashMap<Integer, Integer>();
mapSup = new HashMap<Integer, Integer>();
     // az—initializing MISs————–
  //  writer1 = new BufferedWriter(new FileWriter(MISIn));
  calcMIS(input,Misout);
  initMISfromFile(MISIn);

     // reset the number of frequent itemsets to 0
     itemsetCount = 0;
     
     // create the object for writing the output file
     writer = new BufferedWriter(new FileWriter(output));

     // (2) Scan the database to build the initial FP-Tree
     // Before inserting a transaction in the FPTree, we sort the items
     // by decreasing order of MIS.
   tree = new MISTree();

     BufferedReader reader = new BufferedReader(new FileReader(input));
     String line;
     // read the transaction database line (transaction) by line
     // until the end of file
     while (((line = reader.readLine()) != null)) {
       // split the current transaction into items (they are separated by spaces)
       String[] lineSplited = line.split(” “);
       List<Integer> transaction = new ArrayList<Integer>();
       
       // for each item in the transaction
       for (String itemString : lineSplited) {
         // convert item to integer
         Integer item = Integer.parseInt(itemString);
         
         // increase the support of the item by 1
         Integer count = mapSupport.get(item);
         if (count == null) {
           mapSupport.put(item, 1);
  mapSup.put(item, 1);
         } else {
           mapSupport.put(item, ++count);
  mapSup.put(item, count);
         }
         // all items are added to transactions
         transaction.add(item);
       }
       transactionCount++; // increase the number of transactions
       
       // sort item in the transaction by non increasing order of MIS
       Collections.sort(transaction, this.itemComparator);
       
       // add the sorted transaction to the MISTree.
       tree.addTransaction(transaction);
       
     }// while
     reader.close();  // close the input file
     //writetologinred(“Displaying tree”);
   
  txt_area.setText(“Displaying tree”+”n”);
   
     tree.print(tree.root, txt_area);

     // We create the header table for the tree
     tree.createHeaderList(this.itemComparator);
   
   
   
   
  //here
   
   
   
  try{
  JOptionPane.showMessageDialog(null,”in try”);
     FileOutputStream fout = new FileOutputStream(“d://obj.ser”);
  JOptionPane.showMessageDialog(null,”obj created”);
     ObjectOutputStream foos = new ObjectOutputStream(fout);  
  JOptionPane.showMessageDialog(null,”oos created”);  ///til here i get output later getting error
     foos.writeObject(tree);
  JOptionPane.showMessageDialog(null,”here compltes writeobj”);
  foos.flush();
  JOptionPane.showMessageDialog(null,”after flush”);
     //foos.close();
  fout.close();
  JOptionPane.showMessageDialog(null,”alll”);
     System.out.println(“Done”);
 
    }catch(Exception ex){
      JOptionPane.showMessageDialog(null,”error”);
    }
   
   
   
  //here
   
   
   
  //frqpat.setEnabled(true);
  }

error is like this

Exception in thread “AWT-EventQueue-0”
java.lang.StackOverflowError

  at
java.lang.Exception.<init>(Unknown Source)

  at
java.lang.reflect.InvocationTargetException.<init>(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at java.io.ObjectOutputStream.defaultWriteFields(Unknown
Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at java.io.ObjectOutputStream.defaultWriteFields(Unknown
Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown
Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at java.io.ObjectOutputStream.writeObject0(Unknown
Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at java.io.ObjectOutputStream.writeSerialData(Unknown
Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown
Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown
Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at java.io.ObjectOutputStream.writeObject(Unknown
Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown
Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject(Unknown Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at sun.reflect.GeneratedMethodAccessor4.invoke(Unknown
Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at
java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)

  at java.io.ObjectOutputStream.writeObject(Unknown
Source)

  at
java.util.ArrayList.writeObject(Unknown Source)

  at
sun.reflect.GeneratedMethodAccessor4.invoke(Unknown Source)

  at
sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

  at
java.lang.reflect.Method.invoke(Unknown Source)

  at
java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeSerialData(Unknown Source)

  at
java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)

  at
java.io.ObjectOutputStream.writeObject0(Unknown Source)