Merge "ProgressMonitor: Refactor to use background alarms"

4 files changed, 411 insertions, 158 deletions

diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Diff.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Diff.java
index 506031713a..5cc058950c 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Diff.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Diff.java
@@ -52,6 +52,7 @@ import java.io.BufferedOutputStream;
 import java.io.PrintWriter;
 import java.text.MessageFormat;
 import java.util.List;
+import java.util.concurrent.TimeUnit;
 
 import org.eclipse.jgit.diff.DiffAlgorithm;
 import org.eclipse.jgit.diff.DiffAlgorithm.SupportedAlgorithm;
@@ -189,7 +190,9 @@ class Diff extends TextBuiltin {
 			} else if (newTree == null)
 				newTree = new FileTreeIterator(db);
 
-			diffFmt.setProgressMonitor(new TextProgressMonitor());
+			TextProgressMonitor pm = new TextProgressMonitor();
+			pm.setDelayStart(2, TimeUnit.SECONDS);
+			diffFmt.setProgressMonitor(pm);
 			diffFmt.setPathFilter(pathFilter);
 			if (detectRenames != null)
 				diffFmt.setDetectRenames(detectRenames.booleanValue());
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/BatchingProgressMonitor.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/BatchingProgressMonitor.java
new file mode 100644
index 0000000000..5eb959752b
--- /dev/null
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/BatchingProgressMonitor.java
@@ -0,0 +1,271 @@
+/*
+ * Copyright (C) 2008-2011, Google Inc.
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.eclipse.jgit.lib;
+
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+
+/** ProgressMonitor that batches update events. */
+public abstract class BatchingProgressMonitor implements ProgressMonitor {
+	private static final ScheduledThreadPoolExecutor alarmQueue;
+
+	static final Object alarmQueueKiller;
+
+	static {
+		// To support garbage collection, start our thread but
+		// swap out the thread factory. When our class is GC'd
+		// the alarmQueueKiller will finalize and ask the executor
+		// to shutdown, ending the worker.
+		//
+		int threads = 1;
+		alarmQueue = new ScheduledThreadPoolExecutor(threads,
+				new ThreadFactory() {
+					public Thread newThread(Runnable taskBody) {
+						Thread thr = new Thread("JGit-AlarmQueue");
+						thr.setDaemon(true);
+						return thr;
+					}
+				});
+		alarmQueue.allowCoreThreadTimeOut(false);
+		alarmQueue.setMaximumPoolSize(alarmQueue.getCorePoolSize());
+		alarmQueue.setContinueExistingPeriodicTasksAfterShutdownPolicy(false);
+		alarmQueue.setExecuteExistingDelayedTasksAfterShutdownPolicy(false);
+		alarmQueue.prestartAllCoreThreads();
+
+		// Now that the threads are running, its critical to swap out
+		// our own thread factory for one that isn't in the ClassLoader.
+		// This allows the class to GC.
+		//
+		alarmQueue.setThreadFactory(Executors.defaultThreadFactory());
+
+		alarmQueueKiller = new Object() {
+			@Override
+			protected void finalize() {
+				alarmQueue.shutdownNow();
+			}
+		};
+	}
+
+	private long delayStartTime;
+
+	private TimeUnit delayStartUnit = TimeUnit.MILLISECONDS;
+
+	private Task task;
+
+	/**
+	 * Set an optional delay before the first output.
+	 *
+	 * @param time
+	 *            how long to wait before output. If 0 output begins on the
+	 *            first {@link #update(int)} call.
+	 * @param unit
+	 *            time unit of {@code time}.
+	 */
+	public void setDelayStart(long time, TimeUnit unit) {
+		delayStartTime = time;
+		delayStartUnit = unit;
+	}
+
+	public void start(int totalTasks) {
+		// Ignore the number of tasks.
+	}
+
+	public void beginTask(String title, int work) {
+		endTask();
+		task = new Task(title, work);
+		if (delayStartTime != 0)
+			task.delay(delayStartTime, delayStartUnit);
+	}
+
+	public void update(int completed) {
+		if (task != null)
+			task.update(this, completed);
+	}
+
+	public void endTask() {
+		if (task != null) {
+			task.end(this);
+			task = null;
+		}
+	}
+
+	public boolean isCancelled() {
+		return false;
+	}
+
+	/**
+	 * Update the progress monitor if the total work isn't known,
+	 *
+	 * @param taskName
+	 *            name of the task.
+	 * @param workCurr
+	 *            number of units already completed.
+	 */
+	protected abstract void onUpdate(String taskName, int workCurr);
+
+	/**
+	 * Finish the progress monitor when the total wasn't known in advance.
+	 *
+	 * @param taskName
+	 *            name of the task.
+	 * @param workCurr
+	 *            total number of units processed.
+	 */
+	protected abstract void onEndTask(String taskName, int workCurr);
+
+	/**
+	 * Update the progress monitor when the total is known in advance.
+	 *
+	 * @param taskName
+	 *            name of the task.
+	 * @param workCurr
+	 *            number of units already completed.
+	 * @param workTotal
+	 *            estimated number of units to process.
+	 * @param percentDone
+	 *            {@code workCurr * 100 / workTotal}.
+	 */
+	protected abstract void onUpdate(String taskName, int workCurr,
+			int workTotal, int percentDone);
+
+	/**
+	 * Finish the progress monitor when the total is known in advance.
+	 *
+	 * @param taskName
+	 *            name of the task.
+	 * @param workCurr
+	 *            total number of units processed.
+	 * @param workTotal
+	 *            estimated number of units to process.
+	 * @param percentDone
+	 *            {@code workCurr * 100 / workTotal}.
+	 */
+	protected abstract void onEndTask(String taskName, int workCurr,
+			int workTotal, int percentDone);
+
+	private static class Task implements Runnable {
+		/** Title of the current task. */
+		private final String taskName;
+
+		/** Number of work units, or {@link ProgressMonitor#UNKNOWN}. */
+		private final int totalWork;
+
+		/** True when timer expires and output should occur on next update. */
+		private volatile boolean display;
+
+		/** Scheduled timer, supporting cancellation if task ends early. */
+		private Future<?> timerFuture;
+
+		/** True if the task has displayed anything. */
+		private boolean output;
+
+		/** Number of work units already completed. */
+		private int lastWork;
+
+		/** Percentage of {@link #totalWork} that is done. */
+		private int lastPercent;
+
+		Task(String taskName, int totalWork) {
+			this.taskName = taskName;
+			this.totalWork = totalWork;
+			this.display = true;
+		}
+
+		void delay(long time, TimeUnit unit) {
+			display = false;
+			timerFuture = alarmQueue.schedule(this, time, unit);
+		}
+
+		public void run() {
+			display = true;
+		}
+
+		void update(BatchingProgressMonitor pm, int completed) {
+			lastWork += completed;
+
+			if (totalWork == UNKNOWN) {
+				// Only display once per second, as the alarm fires.
+				if (display) {
+					pm.onUpdate(taskName, lastWork);
+					output = true;
+					restartTimer();
+				}
+			} else {
+				// Display once per second or when 1% is done.
+				int currPercent = lastWork * 100 / totalWork;
+				if (display) {
+					pm.onUpdate(taskName, lastWork, totalWork, currPercent);
+					output = true;
+					restartTimer();
+					lastPercent = currPercent;
+				} else if (currPercent != lastPercent) {
+					pm.onUpdate(taskName, lastWork, totalWork, currPercent);
+					output = true;
+					lastPercent = currPercent;
+				}
+			}
+		}
+
+		private void restartTimer() {
+			display = false;
+			timerFuture = alarmQueue.schedule(this, 1, TimeUnit.SECONDS);
+		}
+
+		void end(BatchingProgressMonitor pm) {
+			if (output) {
+				if (totalWork == UNKNOWN) {
+					pm.onEndTask(taskName, lastWork);
+				} else {
+					int pDone = lastWork * 100 / totalWork;
+					pm.onEndTask(taskName, lastWork, totalWork, pDone);
+				}
+			}
+			if (timerFuture != null)
+				timerFuture.cancel(false /* no interrupt */);
+		}
+	}
+}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/TextProgressMonitor.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/TextProgressMonitor.java
index a668b11be8..7e48609070 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/TextProgressMonitor.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/TextProgressMonitor.java
@@ -44,99 +44,103 @@
 
 package org.eclipse.jgit.lib;
 
-/**
- * A simple progress reporter printing on stderr
- */
-public class TextProgressMonitor implements ProgressMonitor {
-	private boolean output;
-
-	private long taskBeganAt;
-
-	private String msg;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.Writer;
 
-	private int lastWorked;
+/** A simple progress reporter printing on a stream. */
+public class TextProgressMonitor extends BatchingProgressMonitor {
+	private final Writer out;
 
-	private int totalWork;
+	private boolean write;
 
 	/** Initialize a new progress monitor. */
 	public TextProgressMonitor() {
-		taskBeganAt = System.currentTimeMillis();
+		this(new PrintWriter(System.err));
 	}
 
-	public void start(final int totalTasks) {
-		// Ignore the number of tasks.
-		taskBeganAt = System.currentTimeMillis();
+	/**
+	 * Initialize a new progress monitor.
+	 *
+	 * @param out
+	 *            the stream to receive messages on.
+	 */
+	public TextProgressMonitor(Writer out) {
+		this.out = out;
+		this.write = true;
 	}
 
-	public void beginTask(final String title, final int total) {
-		endTask();
-		msg = title;
-		lastWorked = 0;
-		totalWork = total;
+	@Override
+	protected void onUpdate(String taskName, int workCurr) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, workCurr);
+		send(s);
 	}
 
-	public void update(final int completed) {
-		if (msg == null)
-			return;
-
-		final int cmp = lastWorked + completed;
-		if (!output && System.currentTimeMillis() - taskBeganAt < 500)
-			return;
-		if (totalWork == UNKNOWN) {
-			display(cmp);
-			System.err.flush();
-		} else {
-			if ((cmp * 100 / totalWork) != (lastWorked * 100) / totalWork) {
-				display(cmp);
-				System.err.flush();
-			}
-		}
-		lastWorked = cmp;
-		output = true;
+	@Override
+	protected void onEndTask(String taskName, int workCurr) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, workCurr);
+		s.append("\n");
+		send(s);
 	}
 
-	private void display(final int cmp) {
-		final StringBuilder m = new StringBuilder();
-		m.append('\r');
-		m.append(msg);
-		m.append(": ");
-		while (m.length() < 25)
-			m.append(' ');
+	private void format(StringBuilder s, String taskName, int workCurr) {
+		s.append("\r");
+		s.append(taskName);
+		s.append(": ");
+		while (s.length() < 25)
+			s.append(' ');
+		s.append(workCurr);
+	}
 
-		if (totalWork == UNKNOWN) {
-			m.append(cmp);
-		} else {
-			final String twstr = String.valueOf(totalWork);
-			String cmpstr = String.valueOf(cmp);
-			while (cmpstr.length() < twstr.length())
-				cmpstr = " " + cmpstr;
-			final int pcnt = (cmp * 100 / totalWork);
-			if (pcnt < 100)
-				m.append(' ');
-			if (pcnt < 10)
-				m.append(' ');
-			m.append(pcnt);
-			m.append("% (");
-			m.append(cmpstr);
-			m.append("/");
-			m.append(twstr);
-			m.append(")");
-		}
+	@Override
+	protected void onUpdate(String taskName, int cmp, int totalWork, int pcnt) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, cmp, totalWork, pcnt);
+		send(s);
+	}
 
-		System.err.print(m);
+	@Override
+	protected void onEndTask(String taskName, int cmp, int totalWork, int pcnt) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, cmp, totalWork, pcnt);
+		s.append("\n");
+		send(s);
 	}
 
-	public boolean isCancelled() {
-		return false;
+	private void format(StringBuilder s, String taskName, int cmp,
+			int totalWork, int pcnt) {
+		s.append("\r");
+		s.append(taskName);
+		s.append(": ");
+		while (s.length() < 25)
+			s.append(' ');
+
+		String endStr = String.valueOf(totalWork);
+		String curStr = String.valueOf(cmp);
+		while (curStr.length() < endStr.length())
+			curStr = " " + curStr;
+		if (pcnt < 100)
+			s.append(' ');
+		if (pcnt < 10)
+			s.append(' ');
+		s.append(pcnt);
+		s.append("% (");
+		s.append(curStr);
+		s.append("/");
+		s.append(endStr);
+		s.append(")");
 	}
 
-	public void endTask() {
-		if (output) {
-			if (totalWork != UNKNOWN)
-				display(totalWork);
-			System.err.println();
+	private void send(StringBuilder s) {
+		if (write) {
+			try {
+				out.write(s.toString());
+				out.flush();
+			} catch (IOException err) {
+				write = false;
+			}
 		}
-		output = false;
-		msg = null;
 	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/SideBandProgressMonitor.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/SideBandProgressMonitor.java
index efce7b1da7..c7b22bdabf 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/SideBandProgressMonitor.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/SideBandProgressMonitor.java
@@ -43,110 +43,85 @@
 
 package org.eclipse.jgit.transport;
 
+import java.io.IOException;
 import java.io.OutputStream;
-import java.io.OutputStreamWriter;
-import java.io.PrintWriter;
 
+import org.eclipse.jgit.lib.BatchingProgressMonitor;
 import org.eclipse.jgit.lib.Constants;
-import org.eclipse.jgit.lib.ProgressMonitor;
 
 /** Write progress messages out to the sideband channel. */
-class SideBandProgressMonitor implements ProgressMonitor {
-	private PrintWriter out;
+class SideBandProgressMonitor extends BatchingProgressMonitor {
+	private final OutputStream out;
 
-	private boolean output;
-
-	private long taskBeganAt;
-
-	private long lastOutput;
-
-	private String msg;
-
-	private int lastWorked;
-
-	private int totalWork;
+	private boolean write;
 
 	SideBandProgressMonitor(final OutputStream os) {
-		out = new PrintWriter(new OutputStreamWriter(os, Constants.CHARSET));
+		out = os;
+		write = true;
 	}
 
-	public void start(final int totalTasks) {
-		// Ignore the number of tasks.
-		taskBeganAt = System.currentTimeMillis();
-		lastOutput = taskBeganAt;
+	@Override
+	protected void onUpdate(String taskName, int workCurr) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, workCurr);
+		s.append("   \r");
+		send(s);
 	}
 
-	public void beginTask(final String title, final int total) {
-		endTask();
-		msg = title;
-		lastWorked = 0;
-		totalWork = total;
+	@Override
+	protected void onEndTask(String taskName, int workCurr) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, workCurr);
+		s.append(", done\n");
+		send(s);
 	}
 
-	public void update(final int completed) {
-		if (msg == null)
-			return;
-
-		final int cmp = lastWorked + completed;
-		final long now = System.currentTimeMillis();
-		if (!output && now - taskBeganAt < 500)
-			return;
-		if (totalWork == UNKNOWN) {
-			if (now - lastOutput >= 500) {
-				display(cmp, null);
-				lastOutput = now;
-			}
-		} else {
-			if ((cmp * 100 / totalWork) != (lastWorked * 100) / totalWork
-					|| now - lastOutput >= 500) {
-				display(cmp, null);
-				lastOutput = now;
-			}
-		}
-		lastWorked = cmp;
-		output = true;
+	private void format(StringBuilder s, String taskName, int workCurr) {
+		s.append(taskName);
+		s.append(": ");
+		s.append(workCurr);
 	}
 
-	private void display(final int cmp, final String eol) {
-		final StringBuilder m = new StringBuilder();
-		m.append(msg);
-		m.append(": ");
+	@Override
+	protected void onUpdate(String taskName, int cmp, int totalWork, int pcnt) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, cmp, totalWork, pcnt);
+		s.append("   \r");
+		send(s);
+	}
 
-		if (totalWork == UNKNOWN) {
-			m.append(cmp);
-		} else {
-			final int pcnt = (cmp * 100 / totalWork);
-			if (pcnt < 100)
-				m.append(' ');
-			if (pcnt < 10)
-				m.append(' ');
-			m.append(pcnt);
-			m.append("% (");
-			m.append(cmp);
-			m.append("/");
-			m.append(totalWork);
-			m.append(")");
-		}
-		if (eol != null)
-			m.append(eol);
-		else
-			m.append("   \r");
-		out.print(m);
-		out.flush();
+	@Override
+	protected void onEndTask(String taskName, int cmp, int totalWork, int pcnt) {
+		StringBuilder s = new StringBuilder();
+		format(s, taskName, cmp, totalWork, pcnt);
+		s.append("\n");
+		send(s);
 	}
 
-	public boolean isCancelled() {
-		return false;
+	private void format(StringBuilder s, String taskName, int cmp,
+			int totalWork, int pcnt) {
+		s.append(taskName);
+		s.append(": ");
+		if (pcnt < 100)
+			s.append(' ');
+		if (pcnt < 10)
+			s.append(' ');
+		s.append(pcnt);
+		s.append("% (");
+		s.append(cmp);
+		s.append("/");
+		s.append(totalWork);
+		s.append(")");
 	}
 
-	public void endTask() {
-		if (output) {
-			if (totalWork == UNKNOWN)
-				display(lastWorked, ", done\n");
-			else
-				display(totalWork, "\n");
+	private void send(StringBuilder s) {
+		if (write) {
+			try {
+				out.write(Constants.encode(s.toString()));
+				out.flush();
+			} catch (IOException err) {
+				write = false;
+			}
 		}
-		output = false;
-		msg = null;
 	}
 }