/* * 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 com.google.common.annotations.Beta; import com.google.common.annotations.GwtIncompatible; import com.google.errorprone.annotations.CanIgnoreReturnValue; import java.util.concurrent.Callable; import java.util.concurrent.ExecutionException; import java.util.concurrent.TimeUnit; import java.util.concurrent.TimeoutException; /** * Imposes a time limit on method calls. * * @author Kevin Bourrillion * @author Jens Nyman * @since 1.0 */ @Beta @GwtIncompatible public interface TimeLimiter { /** * Returns an instance of {@code interfaceType} that delegates all method calls to the * {@code target} object, enforcing the specified time limit on each call. This time-limited * delegation is also performed for calls to {@link Object#equals}, {@link Object#hashCode}, and * {@link Object#toString}. * * <p>If the target method call finishes before the limit is reached, the return value or * exception is propagated to the caller exactly as-is. If, on the other hand, the time limit is * reached, the proxy will attempt to abort the call to the target, and will throw an * {@link UncheckedTimeoutException} to the caller. * * <p>It is important to note that the primary purpose of the proxy object is to return control to * the caller when the timeout elapses; aborting the target method call is of secondary concern. * The particular nature and strength of the guarantees made by the proxy is * implementation-dependent. However, it is important that each of the methods on the target * object behaves appropriately when its thread is interrupted. * * <p>For example, to return the value of {@code target.someMethod()}, but substitute {@code * DEFAULT_VALUE} if this method call takes over 50 ms, you can use this code: * * <pre> * TimeLimiter limiter = . . .; * TargetType proxy = limiter.newProxy( * target, TargetType.class, 50, TimeUnit.MILLISECONDS); * try { * return proxy.someMethod(); * } catch (UncheckedTimeoutException e) { * return DEFAULT_VALUE; * } * </pre> * * @param target the object to proxy * @param interfaceType the interface you wish the returned proxy to implement * @param timeoutDuration with timeoutUnit, the maximum length of time that callers are willing to * wait on each method call to the proxy * @param timeoutUnit with timeoutDuration, the maximum length of time that callers are willing to * wait on each method call to the proxy * @return a time-limiting proxy * @throws IllegalArgumentException if {@code interfaceType} is a regular class, enum, or * annotation type, rather than an interface */ <T> T newProxy(T target, Class<T> interfaceType, long timeoutDuration, TimeUnit timeoutUnit); /** * Invokes a specified Callable, timing out after the specified time limit. If the target method * call finished before the limit is reached, the return value or exception is propagated to the * caller exactly as-is. If, on the other hand, the time limit is reached, we attempt to abort the * call to the target, and throw an {@link UncheckedTimeoutException} to the caller. * * @param callable the Callable to execute * @param timeoutDuration with timeoutUnit, the maximum length of time to wait * @param timeoutUnit with timeoutDuration, the maximum length of time to wait * @param interruptible whether to respond to thread interruption by aborting the operation and * throwing InterruptedException; if false, the operation is allowed to complete or time out, * and the current thread's interrupt status is re-asserted. * @return the result returned by the Callable * @throws InterruptedException if {@code interruptible} is true and our thread is interrupted * during execution * @throws UncheckedTimeoutException if the time limit is reached * @deprecated Use one of the other {@code call[Uninterruptibly]WithTimeout()} or {@code * run[Uninterruptibly]WithTimeout()} methods. This method is scheduled to be removed in Guava * 23.0. */ @Deprecated @CanIgnoreReturnValue <T> T callWithTimeout( Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit, boolean interruptible) throws Exception; /** * Invokes a specified Callable, timing out after the specified time limit. If the target method * call finishes before the limit is reached, the return value or a wrapped exception is * propagated. If, on the other hand, the time limit is reached, we attempt to abort the call to * the target, and throw a {@link TimeoutException} to the caller. * * @param callable the Callable to execute * @param timeoutDuration with timeoutUnit, the maximum length of time to wait * @param timeoutUnit with timeoutDuration, the maximum length of time to wait * @return the result returned by the Callable * @throws TimeoutException if the time limit is reached * @throws InterruptedException if the current thread was interrupted during execution * @throws ExecutionException if {@code callable} throws a checked exception * @throws UncheckedExecutionException if {@code callable} throws a {@code RuntimeException} * @throws ExecutionError if {@code callable} throws an {@code Error} * @since 22.0 */ <T> T callWithTimeout(Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException, InterruptedException, ExecutionException; /** * Invokes a specified Callable, timing out after the specified time limit. If the target method * call finishes before the limit is reached, the return value or a wrapped exception is * propagated. If, on the other hand, the time limit is reached, we attempt to abort the call to * the target, and throw a {@link TimeoutException} to the caller. * * <p>The difference with {@link #callWithTimeout(Callable, long, TimeUnit)} is that this method * will ignore interrupts on the current thread. * * @param callable the Callable to execute * @param timeoutDuration with timeoutUnit, the maximum length of time to wait * @param timeoutUnit with timeoutDuration, the maximum length of time to wait * @return the result returned by the Callable * @throws TimeoutException if the time limit is reached * @throws ExecutionException if {@code callable} throws a checked exception * @throws UncheckedExecutionException if {@code callable} throws a {@code RuntimeException} * @throws ExecutionError if {@code callable} throws an {@code Error} * @since 22.0 */ <T> T callUninterruptiblyWithTimeout( Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException, ExecutionException; /** * Invokes a specified Runnable, timing out after the specified time limit. If the target method * run finishes before the limit is reached, this method returns or a wrapped exception is * propagated. If, on the other hand, the time limit is reached, we attempt to abort the run, and * throw a {@link TimeoutException} to the caller. * * @param runnable the Runnable to execute * @param timeoutDuration with timeoutUnit, the maximum length of time to wait * @param timeoutUnit with timeoutDuration, the maximum length of time to wait * @throws TimeoutException if the time limit is reached * @throws InterruptedException if the current thread was interrupted during execution * @throws UncheckedExecutionException if {@code runnable} throws a {@code RuntimeException} * @throws ExecutionError if {@code runnable} throws an {@code Error} * @since 22.0 */ void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException, InterruptedException; /** * Invokes a specified Runnable, timing out after the specified time limit. If the target method * run finishes before the limit is reached, this method returns or a wrapped exception is * propagated. If, on the other hand, the time limit is reached, we attempt to abort the run, and * throw a {@link TimeoutException} to the caller. * * <p>The difference with {@link #runWithTimeout(Runnable, long, TimeUnit)} is that this method * will ignore interrupts on the current thread. * * @param runnable the Runnable to execute * @param timeoutDuration with timeoutUnit, the maximum length of time to wait * @param timeoutUnit with timeoutDuration, the maximum length of time to wait * @throws TimeoutException if the time limit is reached * @throws UncheckedExecutionException if {@code runnable} throws a {@code RuntimeException} * @throws ExecutionError if {@code runnable} throws an {@code Error} * @since 22.0 */ void runUninterruptiblyWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit) throws TimeoutException; }