/** Illustrate cloning a subclass of a cloneable class. **/
public class ExampleDeep extends Example {

  ExampleDeep (int num) {
    super (num);
  } // const

  public Object clone () {

  // First make exact bitwise copy
    ExampleDeep copy =  (ExampleDeep)super.clone ();

    // A new array of references to Integer objects
    // is created
    copy.fIarray = new Integer[copy.fNum];

    // Then the new Integer objects given same internal
    // values as the original
    for (int i=0; i < copy.fNum; i++) {
      copy.fIarray[i] =
          new Integer (fIarray[i].intValue ());
    }
    return copy;
  } // clone

  public static void main (String [] args)
  {
    ExampleDeep ex   =  new ExampleDeep (5);
    ExampleDeep copy =  (ExampleDeep) ex.clone ();

    // Change a value in the original array.
    ex.fIarray[0] = new Integer (1234567);

    // But  the copy's value unchanged since it references
    // a different array.
    System.out.println ("Original iarray[0] = " + ex.fIarray[0]);
    System.out.println ("Copy     iarray[0] = " + copy.fIarray[0]);

  } // main

} // ExampleDeep

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

/** Include Outputable interface if needed. **/
public class CloningJApplet8 extends JApplet
             implements ActionListener
{
  // A Swing fTextArea for display of string info
  JTextArea fTextArea ;

  // Flag for whether the applet is in a browser
  // or running via the main () below.
  boolean fInBrowser = true;

  ShallowClass fShallowClass;
  DeepClass fDeepClass;

  public void init () {

    // Create a User Interface with a TextArea with sroll bars
    // and a Go button to initiate processing and a Clear button
    // to clear the TextArea.

    JPanel panel = new JPanel (new BorderLayout ());

    // Create an instance of a fTextArea
    fTextArea = new JTextArea ();
    fTextArea.setEditable (false);

    // Add to a scroll pane so that a long list of
    // computations can be seen.
    JScrollPane area_scroll_pane = new JScrollPane (fTextArea);

    panel.add (area_scroll_pane,"Center");

    JButton go_button = new JButton ("Shallow");
    go_button.addActionListener (this);

    JButton clear_button = new JButton ("Deep");
    clear_button.addActionListener (this);

    JButton exit_button = new JButton ("Exit");
    exit_button.addActionListener (this);

    JPanel control_panel = new JPanel ();
    control_panel.add (go_button);
    control_panel.add (clear_button);
    control_panel.add (exit_button);

    panel.add (control_panel,"South");
    // Add text area with scrolling to the content pane.
    add (panel);

  } // init

  // Can use the start () method, which is called after
  // init () and the display has been created.
  public void start () {
    // Put task code here that will generate text
    // for the fTextArea.
  } // start

  public void actionPerformed (ActionEvent e) {
    String source = e.getActionCommand ();
    if ( source.equals ("Shallow"))
        shallowClone ();
    else if ( source.equals ("Deep") )
        deepClone ();
    else if (!fInBrowser)
        System.exit (0);
  } // actionPerformed

  public void shallowClone () {
    ShallowClass copy;

    fShallowClass = new ShallowClass (5);
    copy =  (ShallowClass)fShallowClass.clone ();

    // Modify original data
    fShallowClass.setData (4, 1234567);
    output ("Original = ", fShallowClass);
    output ("Clone    = ", copy);
  } // shallowClone

  public void deepClone () {
    DeepClass copy;
    fDeepClass = new DeepClass (5);

    copy =  (DeepClass)fDeepClass.clone ();

    // Modify original data
    fDeepClass.setData (4, 12345767);
    output ("Original = ", fDeepClass);
    output ("Clone    = ", copy);

  } // deepClone

  public void output (String str, ShallowClass obj) {
    fTextArea.append (str);
    Integer [] data = obj.getData ();
    for (int i=0; i < 5; i++)
       fTextArea.append (data[i]+" ");
    fTextArea.append ("\n");
  } // output

  public static void main (String[] args) {
    // *** Modify these values for the particular program.
    int frame_width=350;
    int frame_height=350;

    // *** Modify applet subclass name to that of the program
    CloningJApplet8 applet = new CloningJApplet8 ();
    applet.fInBrowser = false;

    // Note that init () invoked before adding to frame.
    // So don't use width/height info in init () since those
    // parameters not yet set.
    applet.init ();

    // Following anonymous class used to close window & exit program
    JFrame f = new JFrame ("Frame & Image Demo");
    f.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
    // Add applet to the frame

    f.getContentPane ().add (applet);
    f.setSize (new Dimension (frame_width,frame_height));
    f.setVisible (true);
  }
} // main

class ShallowClass implements Cloneable {

  Integer [] fData = null;
  int fNumData = 5;

  ShallowClass ()
  {}

  ShallowClass (int num) {
    fNumData = num;
    makeData ();
  }

  ShallowClass (Integer [] dat) {
    fData = dat;
  }

  void makeData () {
    Random ran = new Random ();
    fData = new Integer[fNumData];
    for (int i=0; i < fNumData; i++)
    {
      fData[i] = new Integer (ran.nextInt (10000));
    }
  } // makeData

  Integer [] getData () {
    return fData;
  }

  void setData (int element, int val) {
    if (element < fNumData)
       fData[element] = new Integer (val);
  }

  public Object clone (){
    try {
      // The clone's data is same as the original
      return  (ShallowClass)super.clone ();
    }
    catch  (CloneNotSupportedException e ) {
      throw new Error ("This should never happen!");
    }
  }
} // ShallowClass

class DeepClass extends ShallowClass {
  DeepClass ()
  { }

  DeepClass (int num)
  { super (num); }

  DeepClass (Integer [] dat)
  { super (dat);}

  void setData (Integer [] dat)
  { fData = dat;}

  public Object clone (){
    // First make copy of the data
    Integer [] clone_data = new Integer[fNumData];
    for (int i=0; i < fNumData; i++) {
      // New Integer objects but same values
      clone_data[i] = new Integer (fData[i].intValue () );
    }

    // Create a new instance of DeepClass with
    // the new data array.

      DeepClass copy =  (DeepClass)super.clone ();
      copy.setData (clone_data);
      return copy;
  } // clone

} // DeepClass

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