/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common
* Development and Distribution License("CDDL") (collectively, the
* "License"). You may not use this file except in compliance with the
* License. You can obtain a copy of the License at
* http://www.netbeans.org/cddl-gplv2.html
* or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
* specific language governing permissions and limitations under the
* License. When distributing the software, include this License Header
* Notice in each file and include the License file at
* nbbuild/licenses/CDDL-GPL-2-CP. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the
* License Header, with the fields enclosed by brackets [] replaced by
* your own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Contributor(s):
*
* The Original Software is NetBeans. The Initial Developer of the Original
* Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
* Microsystems, Inc. All Rights Reserved.
*
* If you wish your version of this file to be governed by only the CDDL
* or only the GPL Version 2, indicate your decision by adding
* "[Contributor] elects to include this software in this distribution
* under the [CDDL or GPL Version 2] license." If you do not indicate a
* single choice of license, a recipient has the option to distribute
* your version of this file under either the CDDL, the GPL Version 2 or
* to extend the choice of license to its licensees as provided above.
* However, if you add GPL Version 2 code and therefore, elected the GPL
* Version 2 license, then the option applies only if the new code is
* made subject to such option by the copyright holder.
*/
package threaddemo;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.TimerTask;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.Timer;
/**
* Displays information about any long pauses in the AWT thread.
* @author Jesse Glick
*/
final class Monitor extends JPanel implements ActionListener {
private static final int DELAY_CPU = 100; // msec between AWT pings
private static final long DELAY_HEAP = 1000; // msec between heap recalcs
private static final long GRACE = 500; // msec permitted without access
private long last;
private final Timer t1;
private final java.util.Timer t2;
private final TimerTask task;
private final JTextField blockageField;
private final JTextField heapField;
private static final NumberFormat format = new DecimalFormat("0.00");
private JCheckBox heapLiveCheckBox;
private boolean heapLive;
public Monitor() {
setLayout(new GridLayout(3, 1));
t1 = new Timer(DELAY_CPU, this);
t1.setRepeats(true);
t2 = new java.util.Timer(true);
task = new TimerTask() {
public void run() {
updateHeap();
}
};
last = System.currentTimeMillis();
JPanel sub = new JPanel();
sub.add(new JLabel("Last blockage above " + GRACE + "msec:"));
blockageField = new JTextField(10);
Font font = new Font("Monospaced", Font.PLAIN, blockageField.getFont().getSize());
blockageField.setFont(font);
blockageField.setEditable(false);
sub.add(blockageField);
add(sub);
sub = new JPanel();
sub.add(new JLabel("Heap:"));
heapField = new JTextField(10);
heapField.setFont(font);
heapField.setEditable(false);
sub.add(heapField);
heapLiveCheckBox = new JCheckBox("Immediate Heap Updates");
heapLiveCheckBox.setMnemonic('h');
sub.add(heapLiveCheckBox);
add(sub);
sub = new JPanel();
JButton gc = new JButton("GC");
gc.setMnemonic('g');
gc.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ev) {
System.gc();
System.runFinalization();
System.gc();
}
});
sub.add(gc);
add(sub);
}
public void addNotify() {
super.addNotify();
t1.start();
t2.schedule(task, 0L, DELAY_HEAP);
}
public void removeNotify() {
t1.stop();
t2.cancel();
}
public void actionPerformed(ActionEvent e) {
long now = System.currentTimeMillis();
long block = now - last;
if (block > GRACE) {
System.err.println("AWT blocked for " + block + "msec");
blockageField.setText(Long.toString(block) + "msec");
blockageField.paintImmediately(0, 0, blockageField.getWidth(), blockageField.getHeight());
}
last = now;
// Also update heapLive since we are in AWT:
heapLive = heapLiveCheckBox.isSelected();
}
private void updateHeap() {
// setText is thread-safe:
heapField.setText(format.format(heapUsedMega()) + "Mb");
if (heapLive) {
// Show live updates even when AWT is blocked.
// Note that this can sometimes cause weird painting problems
// in other windows, so off by default.
heapField.paintImmediately(0, 0, heapField.getWidth(), heapField.getHeight());
}
}
private static float heapUsedMega() {
Runtime r = Runtime.getRuntime();
return (r.totalMemory() - r.freeMemory()) / 1024.0f / 1024.0f;
}
}
|