001/*
002 * Copyright (C) 2006 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
005 * in compliance with the License. You may obtain a copy of the License at
006 *
007 * http://www.apache.org/licenses/LICENSE-2.0
008 *
009 * Unless required by applicable law or agreed to in writing, software distributed under the License
010 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
011 * or implied. See the License for the specific language governing permissions and limitations under
012 * the License.
013 */
014
015package com.google.common.util.concurrent;
016
017import com.google.common.annotations.GwtIncompatible;
018import com.google.common.annotations.J2ktIncompatible;
019import com.google.errorprone.annotations.CanIgnoreReturnValue;
020import com.google.errorprone.annotations.DoNotMock;
021import java.util.concurrent.Callable;
022import java.util.concurrent.ExecutionException;
023import java.util.concurrent.TimeUnit;
024import java.util.concurrent.TimeoutException;
025import org.jspecify.annotations.Nullable;
026
027/**
028 * Imposes a time limit on method calls.
029 *
030 * @author Kevin Bourrillion
031 * @author Jens Nyman
032 * @since 1.0
033 */
034@DoNotMock("Use FakeTimeLimiter")
035@J2ktIncompatible
036@GwtIncompatible
037@SuppressWarnings("GoodTime") // should have java.time.Duration overloads
038public interface TimeLimiter {
039
040  /**
041   * Returns an instance of {@code interfaceType} that delegates all method calls to the {@code
042   * target} object, enforcing the specified time limit on each call. This time-limited delegation
043   * is also performed for calls to {@link Object#equals}, {@link Object#hashCode}, and {@link
044   * Object#toString}.
045   *
046   * <p>If the target method call finishes before the limit is reached, the return value or
047   * exception is propagated to the caller exactly as-is. If, on the other hand, the time limit is
048   * reached, the proxy will attempt to abort the call to the target, and will throw an {@link
049   * UncheckedTimeoutException} to the caller.
050   *
051   * <p>It is important to note that the primary purpose of the proxy object is to return control to
052   * the caller when the timeout elapses; aborting the target method call is of secondary concern.
053   * The particular nature and strength of the guarantees made by the proxy is
054   * implementation-dependent. However, it is important that each of the methods on the target
055   * object behaves appropriately when its thread is interrupted.
056   *
057   * <p>For example, to return the value of {@code target.someMethod()}, but substitute {@code
058   * DEFAULT_VALUE} if this method call takes over 50 ms, you can use this code:
059   *
060   * <pre>
061   *   TimeLimiter limiter = . . .;
062   *   TargetType proxy = limiter.newProxy(
063   *       target, TargetType.class, 50, TimeUnit.MILLISECONDS);
064   *   try {
065   *     return proxy.someMethod();
066   *   } catch (UncheckedTimeoutException e) {
067   *     return DEFAULT_VALUE;
068   *   }
069   * </pre>
070   *
071   * @param target the object to proxy
072   * @param interfaceType the interface you wish the returned proxy to implement
073   * @param timeoutDuration with timeoutUnit, the maximum length of time that callers are willing to
074   *     wait on each method call to the proxy
075   * @param timeoutUnit with timeoutDuration, the maximum length of time that callers are willing to
076   *     wait on each method call to the proxy
077   * @return a time-limiting proxy
078   * @throws IllegalArgumentException if {@code interfaceType} is a regular class, enum, or
079   *     annotation type, rather than an interface
080   */
081  <T> T newProxy(T target, Class<T> interfaceType, long timeoutDuration, TimeUnit timeoutUnit);
082
083  /**
084   * Invokes a specified Callable, timing out after the specified time limit. If the target method
085   * call finishes before the limit is reached, the return value or a wrapped exception is
086   * propagated. If, on the other hand, the time limit is reached, we attempt to abort the call to
087   * the target, and throw a {@link TimeoutException} to the caller.
088   *
089   * @param callable the Callable to execute
090   * @param timeoutDuration with timeoutUnit, the maximum length of time to wait
091   * @param timeoutUnit with timeoutDuration, the maximum length of time to wait
092   * @return the result returned by the Callable
093   * @throws TimeoutException if the time limit is reached
094   * @throws InterruptedException if the current thread was interrupted during execution
095   * @throws ExecutionException if {@code callable} throws a checked exception
096   * @throws UncheckedExecutionException if {@code callable} throws a {@code RuntimeException}
097   * @throws ExecutionError if {@code callable} throws an {@code Error}
098   * @since 22.0
099   */
100  @CanIgnoreReturnValue
101  @ParametricNullness
102  <T extends @Nullable Object> T callWithTimeout(
103      Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit)
104      throws TimeoutException, InterruptedException, ExecutionException;
105
106  /**
107   * Invokes a specified Callable, timing out after the specified time limit. If the target method
108   * call finishes before the limit is reached, the return value or a wrapped exception is
109   * propagated. If, on the other hand, the time limit is reached, we attempt to abort the call to
110   * the target, and throw a {@link TimeoutException} to the caller.
111   *
112   * <p>The difference with {@link #callWithTimeout(Callable, long, TimeUnit)} is that this method
113   * will ignore interrupts on the current thread.
114   *
115   * @param callable the Callable to execute
116   * @param timeoutDuration with timeoutUnit, the maximum length of time to wait
117   * @param timeoutUnit with timeoutDuration, the maximum length of time to wait
118   * @return the result returned by the Callable
119   * @throws TimeoutException if the time limit is reached
120   * @throws ExecutionException if {@code callable} throws a checked exception
121   * @throws UncheckedExecutionException if {@code callable} throws a {@code RuntimeException}
122   * @throws ExecutionError if {@code callable} throws an {@code Error}
123   * @since 22.0
124   */
125  @CanIgnoreReturnValue
126  @ParametricNullness
127  <T extends @Nullable Object> T callUninterruptiblyWithTimeout(
128      Callable<T> callable, long timeoutDuration, TimeUnit timeoutUnit)
129      throws TimeoutException, ExecutionException;
130
131  /**
132   * Invokes a specified Runnable, timing out after the specified time limit. If the target method
133   * run finishes before the limit is reached, this method returns or a wrapped exception is
134   * propagated. If, on the other hand, the time limit is reached, we attempt to abort the run, and
135   * throw a {@link TimeoutException} to the caller.
136   *
137   * @param runnable the Runnable to execute
138   * @param timeoutDuration with timeoutUnit, the maximum length of time to wait
139   * @param timeoutUnit with timeoutDuration, the maximum length of time to wait
140   * @throws TimeoutException if the time limit is reached
141   * @throws InterruptedException if the current thread was interrupted during execution
142   * @throws UncheckedExecutionException if {@code runnable} throws a {@code RuntimeException}
143   * @throws ExecutionError if {@code runnable} throws an {@code Error}
144   * @since 22.0
145   */
146  void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)
147      throws TimeoutException, InterruptedException;
148
149  /**
150   * Invokes a specified Runnable, timing out after the specified time limit. If the target method
151   * run finishes before the limit is reached, this method returns or a wrapped exception is
152   * propagated. If, on the other hand, the time limit is reached, we attempt to abort the run, and
153   * throw a {@link TimeoutException} to the caller.
154   *
155   * <p>The difference with {@link #runWithTimeout(Runnable, long, TimeUnit)} is that this method
156   * will ignore interrupts on the current thread.
157   *
158   * @param runnable the Runnable to execute
159   * @param timeoutDuration with timeoutUnit, the maximum length of time to wait
160   * @param timeoutUnit with timeoutDuration, the maximum length of time to wait
161   * @throws TimeoutException if the time limit is reached
162   * @throws UncheckedExecutionException if {@code runnable} throws a {@code RuntimeException}
163   * @throws ExecutionError if {@code runnable} throws an {@code Error}
164   * @since 22.0
165   */
166  void runUninterruptiblyWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)
167      throws TimeoutException;
168}