001/* 002 * Copyright 2002-2020 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.core.task; 018 019/** 020 * A callback interface for a decorator to be applied to any {@link Runnable} 021 * about to be executed. 022 * 023 * <p>Note that such a decorator is not necessarily being applied to the 024 * user-supplied {@code Runnable}/{@code Callable} but rather to the actual 025 * execution callback (which may be a wrapper around the user-supplied task). 026 * 027 * <p>The primary use case is to set some execution context around the task's 028 * invocation, or to provide some monitoring/statistics for task execution. 029 * 030 * <p><b>NOTE:</b> Exception handling in {@code TaskDecorator} implementations 031 * may be limited. Specifically in case of a {@code Future}-based operation, 032 * the exposed {@code Runnable} will be a wrapper which does not propagate 033 * any exceptions from its {@code run} method. 034 * 035 * @author Juergen Hoeller 036 * @since 4.3 037 * @see TaskExecutor#execute(Runnable) 038 * @see SimpleAsyncTaskExecutor#setTaskDecorator 039 * @see org.springframework.core.task.support.TaskExecutorAdapter#setTaskDecorator 040 */ 041public interface TaskDecorator { 042 043 /** 044 * Decorate the given {@code Runnable}, returning a potentially wrapped 045 * {@code Runnable} for actual execution, internally delegating to the 046 * original {@link Runnable#run()} implementation. 047 * @param runnable the original {@code Runnable} 048 * @return the decorated {@code Runnable} 049 */ 050 Runnable decorate(Runnable runnable); 051 052}