// Fig. 6.10: Scoping.java
// A scoping example.
import java.awt.Container;

import javax.swing.*;

public class Scoping extends JApplet {
   JTextArea outputArea;

   // field that is accessible to all methods of this class
   int x = 1; 

   // create applet's GUI
   public void init()
   {
      outputArea = new JTextArea();
      Container container = getContentPane(); 
      container.add( outputArea );

   } // end method init

   // method start called after init completes; start calls
   // methods useLocal and useField
   public void start()
   {
      int x = 5;   // local variable in method start that shadows field x

      outputArea.append( "local x in start is " + x );

      useLocal();  // useLocal has local x
      useField();  // useInstance uses Scoping's field x
      useLocal();  // useLocal reinitializes local x
      useField();  // Scoping's field x retains its value

      outputArea.append( "\n\nlocal x in start is " + x );

   } // end method start

   // useLocal creates and initializes local variable x during each call
   public void useLocal()
   {
      int x = 25;  // initialized each time useLocal is called

      outputArea.append( "\n\nlocal x in useLocal is " + x +
         " after entering useLocal" );
      ++x;
      outputArea.append( "\nlocal x in useLocal is " + x +
         " before exiting useLocal" );

   } // end method useLocal

   // useField modifies Scoping's field x during each call
   public void useField()
   {
      outputArea.append( "\n\nfield x is " + x +
         " on entering useField" );
      x *= 10;
      outputArea.append( "\nfield x is " + x +
         " on exiting useField" );

   } // end method useInstance

} // end class Scoping


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