/*
* Copyright (C) 2014 by Array Systems Computing Inc. http://www.array.ca
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 3 of the License, or (at your option)
* any later version.
* This program 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 General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, see http://www.gnu.org/licenses/
*/
package org.esa.snap.graphbuilder.rcp.progress;
import com.bc.ceres.core.Assert;
import com.bc.ceres.core.ProgressMonitor;
import javax.swing.JLabel;
import javax.swing.JProgressBar;
import javax.swing.SwingUtilities;
import java.util.ArrayList;
import java.util.List;
/**
* A {@link com.bc.ceres.core.ProgressMonitor} which uses a
* Swing's {@link javax.swing.ProgressMonitor} to display progress.
*/
public class LabelBarProgressMonitor implements ProgressMonitor {
public static final String stopCommand = "stop";
public static final String updateCommand = "update";
private final JProgressBar progressBar;
private final JLabel messageLabel;
private double currentWork;
private double totalWork;
private int totalWorkUI;
private int currentWorkUI;
private int lastWorkUI;
private boolean cancelRequested;
private final List<ProgressBarListener> listenerList = new ArrayList<>(1);
public LabelBarProgressMonitor(JProgressBar progressBar) {
this(progressBar, null);
}
public LabelBarProgressMonitor(JProgressBar progressBar, JLabel messageLabel) {
this.progressBar = progressBar;
this.messageLabel = messageLabel;
}
/**
* Notifies that the main task is beginning. This must only be called once
* on a given progress monitor instance.
*
* @param name the name (or description) of the main task
* @param totalWork the total number of work units into which
* the main task is been subdivided. If the value is <code>UNKNOWN</code>
* the implementation is free to indicate progress in a way which
* doesn't require the total number of work units in advance.
*/
public void beginTask(String name, int totalWork) {
Assert.notNull(name, "name");
currentWork = 0.0;
this.totalWork = totalWork;
currentWorkUI = 0;
lastWorkUI = 0;
totalWorkUI = totalWork;
if (messageLabel != null) {
messageLabel.setText(name);
}
cancelRequested = false;
setDescription(name);
progressBar.setMaximum(totalWork);
}
/**
* Notifies that the work is done; that is, either the main task is completed
* or the user canceled it. This method may be called more than once
* (implementations should be prepared to handle this case).
*/
public void done() {
runInUI(new Runnable() {
public void run() {
if (progressBar != null) {
progressBar.setValue(progressBar.getMaximum());
for (final ProgressBarListener listener : listenerList) {
listener.notifyProgressDone();
}
}
if (messageLabel != null) {
messageLabel.setText("");
}
}
});
}
/**
* Internal method to handle scaling correctly. This method
* must not be called by a client. Clients should
* always use the method </code>worked(int)</code>.
*
* @param work the amount of work done
*/
public void internalWorked(double work) {
currentWork += work;
currentWorkUI = (int) (totalWorkUI * currentWork / totalWork);
if (currentWorkUI > lastWorkUI) {
runInUI(new Runnable() {
public void run() {
if (progressBar != null) {
int progress = progressBar.getMinimum() + currentWorkUI;
progressBar.setValue(progress);
for (final ProgressBarListener listener : listenerList) {
listener.notifyProgressStart();
}
}
lastWorkUI = currentWorkUI;
}
});
}
}
/**
* Returns whether cancelation of current operation has been requested.
* Long-running operations should poll to see if cancelation
* has been requested.
*
* @return <code>true</code> if cancellation has been requested,
* and <code>false</code> otherwise
* @see #setCanceled(boolean)
*/
public boolean isCanceled() {
return cancelRequested;
}
/**
* Sets the cancel state to the given value.
*
* @param canceled <code>true</code> indicates that cancelation has
* been requested (but not necessarily acknowledged);
* <code>false</code> clears this flag
* @see #isCanceled()
*/
public void setCanceled(boolean canceled) {
cancelRequested = canceled;
if (canceled) {
done();
}
}
/**
* Sets the task name to the given value. This method is used to
* restore the task label after a nested operation was executed.
* Normally there is no need for clients to call this method.
*
* @param name the name (or description) of the main task
* @see #beginTask(String, int)
*/
public void setTaskName(final String name) {
runInUI(new Runnable() {
public void run() {
if (messageLabel != null) {
messageLabel.setText(name);
}
}
});
}
/**
* Notifies that a subtask of the main task is beginning.
* Subtasks are optional; the main task might not have subtasks.
*
* @param name the name (or description) of the subtask
*/
public void setSubTaskName(final String name) {
if (messageLabel != null) {
messageLabel.setText(name);
}
}
/**
* Notifies that a given number of work unit of the main task
* has been completed. Note that this amount represents an
* installment, as opposed to a cumulative amount of work done
* to date.
*
* @param work the number of work units just completed
*/
public void worked(int work) {
internalWorked(work);
}
////////////////////////////////////////////////////////////////////////
// Stuff to be performed in Swing's event-dispatching thread
private static void runInUI(Runnable task) {
if (SwingUtilities.isEventDispatchThread()) {
task.run();
} else {
SwingUtilities.invokeLater(task);
}
}
private void setDescription(final String description) {
if (messageLabel != null) {
messageLabel.setText(description);
}
}
public void addListener(final ProgressBarListener listener) {
if (!listenerList.contains(listener)) {
listenerList.add(listener);
}
}
public void removeListener(final ProgressBarListener listener) {
listenerList.remove(listener);
}
public interface ProgressBarListener {
void notifyProgressStart();
void notifyProgressDone();
}
}