Console.java

package complexion.common;

// A simple Java Console for your application (Swing version)
// Requires Java 1.1.5 or higher
//
// Disclaimer the use of this source is at your own risk.
//
// Permission to use and distribute into your own applications
//
// RJHM van den Bergh , rvdb@comweb.nl
 
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.io.IOException;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
import java.io.PrintStream;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
 
/**
 * GUI Console, we're going to use this for the server. Stolen from Head, who stole it from
 * somewhere else, thus there are no comments.
 */
public class Console extends WindowAdapter implements WindowListener, ActionListener, Runnable
{
        private JFrame frame;
        private JTextArea textArea;
        private Thread reader;
        private Thread reader2;
        private boolean quit;
                                       
        private final PipedInputStream pin=new PipedInputStream();
        private final PipedInputStream pin2=new PipedInputStream();
 
        Thread errorThrower; // just for testing (Throws an Exception at this Console
       
        public Console()
        {
                // create all components and add them
                frame=new JFrame("Java Console");
                Dimension screenSize=Toolkit.getDefaultToolkit().getScreenSize();
                Dimension frameSize=new Dimension((int)(screenSize.width/2),(int)(screenSize.height/2));
                int x=(int)(frameSize.width/2);
                int y=(int)(frameSize.height/2);
                frame.setBounds(x,y,frameSize.width,frameSize.height);
               
                textArea=new JTextArea();
                textArea.setEditable(false);
                JButton button=new JButton("clear");
               
                frame.getContentPane().setLayout(new BorderLayout());
                frame.getContentPane().add(new JScrollPane(textArea),BorderLayout.CENTER);
                frame.getContentPane().add(button,BorderLayout.SOUTH);
                frame.setVisible(true);        
                frame.setVisible(true);
                frame.addWindowListener(this);         
                button.addActionListener(this);
               
                try
                {
                        PipedOutputStream pout=new PipedOutputStream(this.pin);
                        System.setOut(new PrintStream(pout,true));
                }
                catch (java.io.IOException io)
                {
                        textArea.append("Couldn't redirect STDOUT to this console\n"+io.getMessage());
                }
                catch (SecurityException se)
                {
                        textArea.append("Couldn't redirect STDOUT to this console\n"+se.getMessage());
            }
               
                try
                {
                        PipedOutputStream pout2=new PipedOutputStream(this.pin2);
                        System.setErr(new PrintStream(pout2,true));
                }
                catch (java.io.IOException io)
                {
                        textArea.append("Couldn't redirect STDERR to this console\n"+io.getMessage());
                }
                catch (SecurityException se)
                {
                        textArea.append("Couldn't redirect STDERR to this console\n"+se.getMessage());
            }          
                       
                quit=false; // signals the Threads that they should exit
                               
                // Starting two seperate threads to read from the PipedInputStreams                            
                //
                reader=new Thread(this);
                reader.setDaemon(true);
                reader.start();
                //
                reader2=new Thread(this);      
                reader2.setDaemon(true);       
                reader2.start();
                               
                       
        }
       
        public synchronized void windowClosed(WindowEvent evt)
        {
                quit=true;
                this.notifyAll(); // stop all threads
                try { reader.join(1000);pin.close();   } catch (Exception e){}         
                try { reader2.join(1000);pin2.close(); } catch (Exception e){}
                System.exit(0);
        }              
               
        public synchronized void windowClosing(WindowEvent evt)
        {
                frame.setVisible(false); // default behaviour of JFrame
                frame.dispose();
        }
       
        public synchronized void actionPerformed(ActionEvent evt)
        {
                textArea.setText("");
        }
 
        public synchronized void run()
        {
                try
                {                      
                        while (Thread.currentThread()==reader)
                        {
                                try { this.wait(100);}catch(InterruptedException ie) {}
                                if (pin.available()!=0)
                                {
                                        String input=this.readLine(pin);
                                        textArea.append(input);
                                }
                                if (quit) return;
                        }
               
                        while (Thread.currentThread()==reader2)
                        {
                                try { this.wait(100);}catch(InterruptedException ie) {}
                                if (pin2.available()!=0)
                                {
                                        String input=this.readLine(pin2);
                                        textArea.append(input);
                                }
                                if (quit) return;
                        }                      
                } catch (Exception e)
                {
                        textArea.append("\nConsole reports an Internal error.");
                        textArea.append("The error is: "+e);                   
                }
               
                // just for testing (Throw a Nullpointer after 1 second)
                if (Thread.currentThread()==errorThrower)
                {
                        try { this.wait(1000); }catch(InterruptedException ie){}
                        throw new NullPointerException("Application test: throwing an NullPointerException It should arrive at the console");
                }
 
        }
       
        public synchronized String readLine(PipedInputStream in) throws IOException
        {
                String input="";
                do
                {
                        int available=in.available();
                        if (available==0) break;
                        byte b[]=new byte[available];
                        in.read(b);
                        input=input+new String(b,0,b.length);                                                                                                          
                }while( !input.endsWith("\n") &&  !input.endsWith("\r\n") && !quit);
                return input;
        }      
                       
}