001/* 002 * Copyright 2002-2018 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.remoting.support; 018 019import org.apache.commons.logging.Log; 020import org.apache.commons.logging.LogFactory; 021 022import org.springframework.beans.factory.BeanClassLoaderAware; 023import org.springframework.lang.Nullable; 024import org.springframework.util.ClassUtils; 025 026/** 027 * Generic support base class for remote accessor and exporters, 028 * providing common bean ClassLoader handling. 029 * 030 * @author Juergen Hoeller 031 * @since 2.5.2 032 */ 033public abstract class RemotingSupport implements BeanClassLoaderAware { 034 035 /** Logger available to subclasses. */ 036 protected final Log logger = LogFactory.getLog(getClass()); 037 038 private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader(); 039 040 041 @Override 042 public void setBeanClassLoader(ClassLoader classLoader) { 043 this.beanClassLoader = classLoader; 044 } 045 046 /** 047 * Return the ClassLoader that this accessor operates in, 048 * to be used for deserializing and for generating proxies. 049 */ 050 protected ClassLoader getBeanClassLoader() { 051 return this.beanClassLoader; 052 } 053 054 055 /** 056 * Override the thread context ClassLoader with the environment's bean ClassLoader 057 * if necessary, i.e. if the bean ClassLoader is not equivalent to the thread 058 * context ClassLoader already. 059 * @return the original thread context ClassLoader, or {@code null} if not overridden 060 */ 061 @Nullable 062 protected ClassLoader overrideThreadContextClassLoader() { 063 return ClassUtils.overrideThreadContextClassLoader(getBeanClassLoader()); 064 } 065 066 /** 067 * Reset the original thread context ClassLoader if necessary. 068 * @param original the original thread context ClassLoader, 069 * or {@code null} if not overridden (and hence nothing to reset) 070 */ 071 protected void resetThreadContextClassLoader(@Nullable ClassLoader original) { 072 if (original != null) { 073 Thread.currentThread().setContextClassLoader(original); 074 } 075 } 076 077}