001/* 002 * Copyright 2002-2012 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.aop.interceptor; 018 019import java.io.Serializable; 020 021import org.aopalliance.intercept.MethodInterceptor; 022import org.aopalliance.intercept.MethodInvocation; 023 024import org.springframework.util.ConcurrencyThrottleSupport; 025 026/** 027 * Interceptor that throttles concurrent access, blocking invocations 028 * if a specified concurrency limit is reached. 029 * 030 * <p>Can be applied to methods of local services that involve heavy use 031 * of system resources, in a scenario where it is more efficient to 032 * throttle concurrency for a specific service rather than restricting 033 * the entire thread pool (e.g. the web container's thread pool). 034 * 035 * <p>The default concurrency limit of this interceptor is 1. 036 * Specify the "concurrencyLimit" bean property to change this value. 037 * 038 * @author Juergen Hoeller 039 * @since 11.02.2004 040 * @see #setConcurrencyLimit 041 */ 042@SuppressWarnings("serial") 043public class ConcurrencyThrottleInterceptor extends ConcurrencyThrottleSupport 044 implements MethodInterceptor, Serializable { 045 046 public ConcurrencyThrottleInterceptor() { 047 setConcurrencyLimit(1); 048 } 049 050 @Override 051 public Object invoke(MethodInvocation methodInvocation) throws Throwable { 052 beforeAccess(); 053 try { 054 return methodInvocation.proceed(); 055 } 056 finally { 057 afterAccess(); 058 } 059 } 060 061}