/*
* $Id$
*
* Copyright 2007 Bruno Lowagie.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package com.lowagie.rups.view;
import java.awt.Color;
import java.io.IOException;
import java.io.PipedInputStream;
import java.io.PipedOutputStream;
import java.io.PrintStream;
import java.util.Observable;
import java.util.Observer;
import javax.swing.JTextPane;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultStyledDocument;
import javax.swing.text.Document;
import javax.swing.text.Style;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyleContext;
/**
* A Class that redirects everything written to System.out and System.err
* to a JTextPane.
*/
public class Console implements Observer {
/** Single Console instance. */
private static Console console = null;
/** Custom PrintStream. */
PrintStream printStream;
/** Custom OutputStream. */
PipedOutputStream poCustom;
/** Custom InputStream. */
PipedInputStream piCustom;
/** OutputStream for System.out. */
PipedOutputStream poOut;
/** InputStream for System.out. */
PipedInputStream piOut;
/** OutputStream for System.err. */
PipedOutputStream poErr;
/** InputStream for System.err. */
PipedInputStream piErr;
/** The StyleContext for the Console. */
ConsoleStyleContext styleContext = new ConsoleStyleContext();
/** The text area to which everything is written. */
JTextPane textArea = new JTextPane(new DefaultStyledDocument(styleContext));
/**
* Creates a new Console object.
* @throws IOException
*/
private Console() throws IOException {
// Set up Custom
piCustom = new PipedInputStream();
poCustom = new PipedOutputStream();
printStream = new PrintStream(poCustom);
// Set up System.out
piOut = new PipedInputStream();
poOut = new PipedOutputStream(piOut);
System.setOut(new PrintStream(poOut, true));
// Set up System.err
piErr = new PipedInputStream();
poErr = new PipedOutputStream(piErr);
System.setErr(new PrintStream(poErr, true));
// Add a scrolling text area
textArea.setEditable(false);
// Create reader threads
new ReadWriteThread(piCustom, ConsoleStyleContext.CUSTOM).start();
new ReadWriteThread(piOut, ConsoleStyleContext.SYSTEMOUT).start();
new ReadWriteThread(piErr, ConsoleStyleContext.SYSTEMERR).start();
}
/**
* Console is a Singleton class: you can only get one Console.
*/
public static synchronized Console getInstance() {
if (console == null) {
try {
console = new Console();
} catch (IOException e) {
console = null;
}
}
return console;
}
/**
* @see java.util.Observer#update(java.util.Observable, java.lang.Object)
*/
public void update(Observable observable, Object obj) {
if (RupsMenuBar.CLOSE.equals(obj)) {
textArea.setText("");
}
if (RupsMenuBar.OPEN.equals(obj)) {
textArea.setText("");
}
}
/**
* Allows you to print something to the custom PrintStream.
* @param s the message you want to send to the Console
*/
public static void println(String s) {
PrintStream ps = getInstance().getPrintStream();
if (ps == null) {
System.out.println(s);
}
else {
ps.println(s);
ps.flush();
}
}
/**
* Get the custom PrintStream of the console.
*/
public PrintStream getPrintStream() {
return printStream;
}
/**
* Get the JTextArea to which everything is written.
*/
public JTextPane getTextArea() {
return textArea;
}
/**
* The thread that will write everything to the text area.
*/
class ReadWriteThread extends Thread {
/** The InputStream of this Thread */
PipedInputStream pi;
/** The type (CUSTOM, SYSTEMOUT, SYSTEMERR) of this Thread */
String type;
/** Create the ReaderThread. */
ReadWriteThread(PipedInputStream pi, String type) {
super();
this.pi = pi;
this.type = type;
}
/**
* @see java.lang.Thread#run()
*/
public void run() {
final byte[] buf = new byte[1024];
while (true) {
try {
final int len = pi.read(buf);
if (len == -1) {
break;
}
Document doc = textArea.getDocument();
AttributeSet attset = styleContext.getStyle(type);
String snippet = new String(buf, 0, len);
doc.insertString(doc.getLength(),
snippet, attset);
printStream.print(snippet);
textArea.setCaretPosition(textArea.getDocument().
getLength());
} catch (BadLocationException ex) {
} catch (IOException e) {
}
}
}
}
/**
* The style context defining the styles of each type of PrintStream.
*/
class ConsoleStyleContext extends StyleContext {
/** A Serial Version UID. */
private static final long serialVersionUID = 7253870053566811171L;
/** The name of the Style used for Custom messages */
public static final String CUSTOM = "Custom";
/** The name of the Style used for System.out */
public static final String SYSTEMOUT = "SystemOut";
/** The name of the Style used for System.err */
public static final String SYSTEMERR = "SystemErr";
/** Creates the style context for the Console. */
public ConsoleStyleContext() {
super();
Style root = getStyle(DEFAULT_STYLE);
Style s = addStyle(CUSTOM, root);
StyleConstants.setForeground(s, Color.BLACK);
s = addStyle(SYSTEMOUT, root);
StyleConstants.setForeground(s, Color.GREEN);
s = addStyle(SYSTEMERR, root);
StyleConstants.setForeground(s, Color.RED);
}
}
}