/*
* Copyright 2000-2016 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* @author max
*/
package com.intellij.util.io.storage;
import com.intellij.openapi.Disposable;
import com.intellij.openapi.application.AccessToken;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.util.registry.Registry;
import com.intellij.util.EventDispatcher;
import gnu.trove.THashSet;
import org.jetbrains.annotations.NotNull;
import javax.swing.*;
import java.util.*;
public class HeavyProcessLatch {
private static final Logger LOG = Logger.getInstance("#com.intellij.util.io.storage.HeavyProcessLatch");
public static final HeavyProcessLatch INSTANCE = new HeavyProcessLatch();
private final Set<String> myHeavyProcesses = new THashSet<String>();
private final EventDispatcher<HeavyProcessListener> myEventDispatcher = EventDispatcher.create(HeavyProcessListener.class);
private final EventDispatcher<HeavyProcessListener> myUIProcessDispatcher = EventDispatcher.create(HeavyProcessListener.class);
private volatile Thread myUiActivityThread;
/**
Don't wait forever in case someone forgot to stop prioritizing before waiting for other threads to complete
wait just for 12 seconds; this will be noticeable (and we'll get 2 thread dumps) but not fatal
*/
private static final int MAX_PRIORITIZATION_MILLIS = 12 * 1000;
private volatile long myPrioritizingStarted;
private final List<Runnable> toExecuteOutOfHeavyActivity = new ArrayList<Runnable>();
private HeavyProcessLatch() {
}
/**
* @deprecated use {@link #processStarted(String)} instead
*/
@Deprecated
public void processStarted() {
processStarted("");
}
@NotNull
public AccessToken processStarted(@NotNull final String operationName) {
synchronized (myHeavyProcesses) {
myHeavyProcesses.add(operationName);
}
myEventDispatcher.getMulticaster().processStarted();
return new AccessToken() {
@Override
public void finish() {
processFinished(operationName);
}
};
}
private void processFinished(@NotNull String operationName) {
synchronized (myHeavyProcesses) {
myHeavyProcesses.remove(operationName);
}
myEventDispatcher.getMulticaster().processFinished();
List<Runnable> toRunNow;
synchronized (myHeavyProcesses) {
if (isRunning()) {
toRunNow = Collections.emptyList();
}
else {
toRunNow = new ArrayList<Runnable>(toExecuteOutOfHeavyActivity);
toExecuteOutOfHeavyActivity.clear();
}
}
for (Runnable runnable : toRunNow) {
try {
runnable.run();
}
catch (Exception e) {
LOG.error(e);
}
}
}
public boolean isRunning() {
synchronized (myHeavyProcesses) {
return !myHeavyProcesses.isEmpty();
}
}
public String getRunningOperationName() {
synchronized (myHeavyProcesses) {
return myHeavyProcesses.isEmpty() ? null : myHeavyProcesses.iterator().next();
}
}
public interface HeavyProcessListener extends EventListener {
void processStarted();
void processFinished();
}
public void addListener(@NotNull HeavyProcessListener listener,
@NotNull Disposable parentDisposable) {
myEventDispatcher.addListener(listener, parentDisposable);
}
public void addUIActivityListener(@NotNull HeavyProcessListener listener,
@NotNull Disposable parentDisposable) {
myUIProcessDispatcher.addListener(listener, parentDisposable);
}
public void executeOutOfHeavyProcess(@NotNull Runnable runnable) {
boolean runNow;
synchronized (myHeavyProcesses) {
if (isRunning()) {
runNow = false;
toExecuteOutOfHeavyActivity.add(runnable);
}
else {
runNow = true;
}
}
if (runNow) {
runnable.run();
}
}
/**
* Gives current event processed on Swing thread higher priority
* by letting other threads to sleep a bit whenever they call checkCanceled.
* @see #stopThreadPrioritizing()
*/
public void prioritizeUiActivity() {
LOG.assertTrue(SwingUtilities.isEventDispatchThread());
if (!Registry.is("ide.prioritize.ui.thread", false)) {
return;
}
myPrioritizingStarted = System.currentTimeMillis();
myUiActivityThread = Thread.currentThread();
myUIProcessDispatcher.getMulticaster().processStarted();
}
/**
* Removes priority from Swing thread, if present. Should be invoked before a thread starts waiting for other threads in idle mode,
* to ensure those other threads complete ASAP.
* @see #prioritizeUiActivity()
*/
public void stopThreadPrioritizing() {
if (myUiActivityThread == null) return;
myUiActivityThread = null;
myUIProcessDispatcher.getMulticaster().processFinished();
}
/**
* @return whether there is a prioritized thread, but not the current one
*/
public boolean isInsideLowPriorityThread() {
Thread uiThread = myUiActivityThread;
if (uiThread != null && uiThread != Thread.currentThread()) {
Thread.State state = uiThread.getState();
if (state == Thread.State.WAITING || state == Thread.State.TIMED_WAITING || state == Thread.State.BLOCKED) {
return false;
}
long time = System.currentTimeMillis() - myPrioritizingStarted;
if (time < 5) {
return false; // don't sleep when EDT activities are very short (e.g. empty processing of mouseMoved events)
}
if (time > MAX_PRIORITIZATION_MILLIS) {
stopThreadPrioritizing();
return false;
}
return true;
}
return false;
}
/**
* @return whether there is a prioritized thread currently
*/
public boolean hasPrioritizedThread() {
return myUiActivityThread != null;
}
}