com.google.common.util.concurrent.SimpleTimeLimiter Maven / Gradle / Ivy
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/*
* Copyright (C) 2006 The Guava Authors
*
* 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.
*/
package com.google.common.util.concurrent;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.ObjectArrays;
import com.google.common.collect.Sets;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;
/**
* A TimeLimiter that runs method calls in the background using an {@link ExecutorService}. If the
* time limit expires for a given method call, the thread running the call will be interrupted.
*
* @author Kevin Bourrillion
* @author Jens Nyman
* @since 1.0
*/
@Beta
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class SimpleTimeLimiter implements TimeLimiter {
private final ExecutorService executor;
private SimpleTimeLimiter(ExecutorService executor) {
this.executor = checkNotNull(executor);
}
/**
* Creates a TimeLimiter instance using the given executor service to execute method calls.
*
* Warning: using a bounded executor may be counterproductive! If the thread pool fills
* up, any time callers spend waiting for a thread may count toward their time limit, and in this
* case the call may even time out before the target method is ever invoked.
*
* @param executor the ExecutorService that will execute the method calls on the target objects;
* for example, a {@link Executors#newCachedThreadPool()}.
* @since 22.0
*/
public static SimpleTimeLimiter create(ExecutorService executor) {
return new SimpleTimeLimiter(executor);
}
@Override
public T newProxy(
T target, Class interfaceType, long timeoutDuration, TimeUnit timeoutUnit) {
checkNotNull(target);
checkNotNull(interfaceType);
checkNotNull(timeoutUnit);
checkPositiveTimeout(timeoutDuration);
checkArgument(interfaceType.isInterface(), "interfaceType must be an interface type");
Set interruptibleMethods = findInterruptibleMethods(interfaceType);
InvocationHandler handler =
new InvocationHandler() {
@Override
@CheckForNull
public Object invoke(Object obj, Method method, @CheckForNull @Nullable Object[] args)
throws Throwable {
Callable<@Nullable Object> callable =
() -> {
try {
return method.invoke(target, args);
} catch (InvocationTargetException e) {
throw throwCause(e, false /* combineStackTraces */);
}
};
return callWithTimeout(
callable, timeoutDuration, timeoutUnit, interruptibleMethods.contains(method));
}
};
return newProxy(interfaceType, handler);
}
// TODO: replace with version in common.reflect if and when it's open-sourced
private static T newProxy(Class interfaceType, InvocationHandler handler) {
Object object =
Proxy.newProxyInstance(
interfaceType.getClassLoader(), new Class[] {interfaceType}, handler);
return interfaceType.cast(object);
}
private T callWithTimeout(
Callable callable, long timeoutDuration, TimeUnit timeoutUnit, boolean amInterruptible)
throws Exception {
checkNotNull(callable);
checkNotNull(timeoutUnit);
checkPositiveTimeout(timeoutDuration);
Future future = executor.submit(callable);
try {
if (amInterruptible) {
try {
return future.get(timeoutDuration, timeoutUnit);
} catch (InterruptedException e) {
future.cancel(true);
throw e;
}
} else {
return Uninterruptibles.getUninterruptibly(future, timeoutDuration, timeoutUnit);
}
} catch (ExecutionException e) {
throw throwCause(e, true /* combineStackTraces */);
} catch (TimeoutException e) {
future.cancel(true);
throw new UncheckedTimeoutException(e);
}
}
@CanIgnoreReturnValue
@Override
public T callWithTimeout(
Callable callable, long timeoutDuration, TimeUnit timeoutUnit)
throws TimeoutException, InterruptedException, ExecutionException {
checkNotNull(callable);
checkNotNull(timeoutUnit);
checkPositiveTimeout(timeoutDuration);
Future future = executor.submit(callable);
try {
return future.get(timeoutDuration, timeoutUnit);
} catch (InterruptedException | TimeoutException e) {
future.cancel(true /* mayInterruptIfRunning */);
throw e;
} catch (ExecutionException e) {
wrapAndThrowExecutionExceptionOrError(e.getCause());
throw new AssertionError();
}
}
@CanIgnoreReturnValue
@Override
public T callUninterruptiblyWithTimeout(
Callable callable, long timeoutDuration, TimeUnit timeoutUnit)
throws TimeoutException, ExecutionException {
checkNotNull(callable);
checkNotNull(timeoutUnit);
checkPositiveTimeout(timeoutDuration);
Future future = executor.submit(callable);
try {
return Uninterruptibles.getUninterruptibly(future, timeoutDuration, timeoutUnit);
} catch (TimeoutException e) {
future.cancel(true /* mayInterruptIfRunning */);
throw e;
} catch (ExecutionException e) {
wrapAndThrowExecutionExceptionOrError(e.getCause());
throw new AssertionError();
}
}
@Override
public void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)
throws TimeoutException, InterruptedException {
checkNotNull(runnable);
checkNotNull(timeoutUnit);
checkPositiveTimeout(timeoutDuration);
Future future = executor.submit(runnable);
try {
future.get(timeoutDuration, timeoutUnit);
} catch (InterruptedException | TimeoutException e) {
future.cancel(true /* mayInterruptIfRunning */);
throw e;
} catch (ExecutionException e) {
wrapAndThrowRuntimeExecutionExceptionOrError(e.getCause());
throw new AssertionError();
}
}
@Override
public void runUninterruptiblyWithTimeout(
Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException {
checkNotNull(runnable);
checkNotNull(timeoutUnit);
checkPositiveTimeout(timeoutDuration);
Future future = executor.submit(runnable);
try {
Uninterruptibles.getUninterruptibly(future, timeoutDuration, timeoutUnit);
} catch (TimeoutException e) {
future.cancel(true /* mayInterruptIfRunning */);
throw e;
} catch (ExecutionException e) {
wrapAndThrowRuntimeExecutionExceptionOrError(e.getCause());
throw new AssertionError();
}
}
private static Exception throwCause(Exception e, boolean combineStackTraces) throws Exception {
Throwable cause = e.getCause();
if (cause == null) {
throw e;
}
if (combineStackTraces) {
StackTraceElement[] combined =
ObjectArrays.concat(cause.getStackTrace(), e.getStackTrace(), StackTraceElement.class);
cause.setStackTrace(combined);
}
if (cause instanceof Exception) {
throw (Exception) cause;
}
if (cause instanceof Error) {
throw (Error) cause;
}
// The cause is a weird kind of Throwable, so throw the outer exception.
throw e;
}
private static Set findInterruptibleMethods(Class interfaceType) {
Set set = Sets.newHashSet();
for (Method m : interfaceType.getMethods()) {
if (declaresInterruptedEx(m)) {
set.add(m);
}
}
return set;
}
private static boolean declaresInterruptedEx(Method method) {
for (Class exType : method.getExceptionTypes()) {
// debate: == or isAssignableFrom?
if (exType == InterruptedException.class) {
return true;
}
}
return false;
}
private void wrapAndThrowExecutionExceptionOrError(Throwable cause) throws ExecutionException {
if (cause instanceof Error) {
throw new ExecutionError((Error) cause);
} else if (cause instanceof RuntimeException) {
throw new UncheckedExecutionException(cause);
} else {
throw new ExecutionException(cause);
}
}
private void wrapAndThrowRuntimeExecutionExceptionOrError(Throwable cause) {
if (cause instanceof Error) {
throw new ExecutionError((Error) cause);
} else {
throw new UncheckedExecutionException(cause);
}
}
private static void checkPositiveTimeout(long timeoutDuration) {
checkArgument(timeoutDuration > 0, "timeout must be positive: %s", timeoutDuration);
}
}