// Fig. 23.4: PropertiesTest.java
// Demonstrates class Properties of the java.util package.
import java.io.*;
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class PropertiesTest extends JFrame {
   private JLabel status;
   private Properties table;
   private JTextArea display;

   public PropertiesTest()
   {
      super( "Properties Test" );

      table = new Properties();
      Container c = getContentPane();
      JPanel northPanel = new JPanel();
      northPanel.setLayout( new BorderLayout() );
      JPanel northSubPanel = new JPanel();
      JPanel southPanel = new JPanel();

      northSubPanel.add( new JLabel( "Property value" ) );
      final JTextField propVal = new JTextField( 10 );
      northSubPanel.add( propVal );
      northPanel.add( northSubPanel, BorderLayout.NORTH );

      northSubPanel.add( new JLabel( "Property name (key)" ) );
      final JTextField propName = new JTextField( 10 );
      northSubPanel.add( propName );

      display = new JTextArea( 4, 35 );     

      JButton put = new JButton( "Put" );
      put.addActionListener(
         new ActionListener() {
            public void actionPerformed( ActionEvent e )
            {
               Object val = table.put( propName.getText(),
                                       propVal.getText() );

               if ( val == null )
                  showStatus( "Put: " + propName.getText() +
                              " " + propVal.getText() );                                                   
               else
                  showStatus( "Put: " + propName.getText() +                     
                     " " + propVal.getText() +
                     "; Replaced: " + val.toString() );
                              
               listProperties();
            }
         }
      );
      southPanel.setLayout( new GridLayout( 1, 5 ) );
      southPanel.add( put );

      JButton clear = new JButton( "Clear" );
      clear.addActionListener(
         new ActionListener() {
            public void actionPerformed( ActionEvent e )
            {
               table.clear();
               showStatus( "Table in memory cleared" );
               listProperties();
            }
         }
      );
      southPanel.add( clear );

      JButton getProperty = new JButton( "Get property" );
      getProperty.addActionListener(
         new ActionListener() {
            public void actionPerformed( ActionEvent e )
            {
               String val = table.getProperty( 
                  propName.getText() );
             
               if ( val != null )
                  showStatus( "Get property: " +                     
                     propName.getText() + " " +
                     val );
               else
                  showStatus( "Get: " + propName.getText() +                     
                     " not in table" );

               listProperties();
            }
         }
      );
      southPanel.add( getProperty );

      JButton save = new JButton( "Save" );
      save.addActionListener(
         new ActionListener() {
            public void actionPerformed( ActionEvent e )
            {
               try {
                  FileOutputStream output;

                  output = new FileOutputStream( "props.dat" );
                  table.store( output, "Sample Properties" );
                  output.close();
                  listProperties();
               }
               catch( IOException ex ) {
                  showStatus( ex.toString() );
               }
            }
         }
      );
      southPanel.add( save );

      JButton load = new JButton( "Load" );
      load.addActionListener(
         new ActionListener() {
            public void actionPerformed( ActionEvent e )
            {
               try {
                  FileInputStream input;

                  input = new FileInputStream( "props.dat" );
                  table.load( input );
                  input.close();
                  listProperties();
               }
               catch( IOException ex ) {
                  showStatus( ex.toString() );
               }
            }
         }
      ); 
      southPanel.add( load );

      status = new JLabel();
      northPanel.add( status, BorderLayout.SOUTH );

      c.add( northPanel, BorderLayout.NORTH );
      c.add( new JScrollPane( display ), BorderLayout.CENTER );
      c.add( southPanel, BorderLayout.SOUTH );

      setSize( 550, 225 );
      show();
   }

   public void listProperties()
   {
      StringBuffer buf = new StringBuffer();
      String pName, pVal;

      Enumeration enum = table.propertyNames();

      while( enum.hasMoreElements() ) {
         pName = enum.nextElement().toString();
         pVal = table.getProperty( pName );
         buf.append( pName ).append( '\t' );
         buf.append( pVal ).append( '\n' );
      }

      display.setText( buf.toString() );
   }

   public void showStatus( String s )
   {
      status.setText( s );
   }

   public static void main( String args[] )
   {
      PropertiesTest app = new PropertiesTest();
      app.addWindowListener(
         new WindowAdapter() {
            public void windowClosing( WindowEvent e )
            {
               System.exit( 0 );
            }
         }
      );
   }
}

/**************************************************************************
 * (C) Copyright 1999 by Deitel & Associates, Inc. and Prentice Hall.     *
 * All Rights Reserved.                                                   *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
 *************************************************************************/