All Downloads are FREE. Search and download functionalities are using the official Maven repository.

com.google.common.util.concurrent.TimeLimiter Maven / Gradle / Ivy

The newest version!
/*
 * 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 java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;

/**
 * Produces proxies that impose a time limit on method
 * calls to the proxied object.  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:
 * 
 *   TimeLimiter limiter = . . .;
 *   TargetType proxy = limiter.newProxy(
 *       target, TargetType.class, 50, TimeUnit.MILLISECONDS);
 *   try {
 *     return proxy.someMethod();
 *   } catch (UncheckedTimeoutException e) {
 *     return DEFAULT_VALUE;
 *   }
 * 
*

Please see {@code SimpleTimeLimiterTest} for more usage examples. * * @author Kevin Bourrillion * @since 1.0 */ @Beta 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}. *

* 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. *

* 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. * * @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 newProxy(T target, Class 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. *

* Warning: The future of this method is in doubt. It may be nuked, or * changed significantly. * * @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 * @throws Exception */ T callWithTimeout(Callable callable, long timeoutDuration, TimeUnit timeoutUnit, boolean interruptible) throws Exception; }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy