001/* 002 * Copyright 2002-2019 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.context.weaving; 018 019import java.lang.instrument.ClassFileTransformer; 020 021import org.apache.commons.logging.Log; 022import org.apache.commons.logging.LogFactory; 023 024import org.springframework.beans.factory.BeanClassLoaderAware; 025import org.springframework.beans.factory.DisposableBean; 026import org.springframework.instrument.InstrumentationSavingAgent; 027import org.springframework.instrument.classloading.InstrumentationLoadTimeWeaver; 028import org.springframework.instrument.classloading.LoadTimeWeaver; 029import org.springframework.instrument.classloading.ReflectiveLoadTimeWeaver; 030import org.springframework.instrument.classloading.glassfish.GlassFishLoadTimeWeaver; 031import org.springframework.instrument.classloading.jboss.JBossLoadTimeWeaver; 032import org.springframework.instrument.classloading.tomcat.TomcatLoadTimeWeaver; 033import org.springframework.instrument.classloading.weblogic.WebLogicLoadTimeWeaver; 034import org.springframework.instrument.classloading.websphere.WebSphereLoadTimeWeaver; 035import org.springframework.lang.Nullable; 036import org.springframework.util.Assert; 037 038/** 039 * Default {@link LoadTimeWeaver} bean for use in an application context, 040 * decorating an automatically detected internal {@code LoadTimeWeaver}. 041 * 042 * <p>Typically registered for the default bean name "{@code loadTimeWeaver}"; 043 * the most convenient way to achieve this is Spring's 044 * {@code <context:load-time-weaver>} XML tag or {@code @EnableLoadTimeWeaving} 045 * on a {@code @Configuration} class. 046 * 047 * <p>This class implements a runtime environment check for obtaining the 048 * appropriate weaver implementation. As of Spring Framework 5.0, it detects 049 * Oracle WebLogic 10+, GlassFish 4+, Tomcat 8+, WildFly 8+, IBM WebSphere 8.5+, 050 * {@link InstrumentationSavingAgent Spring's VM agent}, and any {@link ClassLoader} 051 * supported by Spring's {@link ReflectiveLoadTimeWeaver} (such as Liberty's). 052 * 053 * @author Juergen Hoeller 054 * @author Ramnivas Laddad 055 * @author Costin Leau 056 * @since 2.5 057 * @see org.springframework.context.ConfigurableApplicationContext#LOAD_TIME_WEAVER_BEAN_NAME 058 */ 059public class DefaultContextLoadTimeWeaver implements LoadTimeWeaver, BeanClassLoaderAware, DisposableBean { 060 061 protected final Log logger = LogFactory.getLog(getClass()); 062 063 @Nullable 064 private LoadTimeWeaver loadTimeWeaver; 065 066 067 public DefaultContextLoadTimeWeaver() { 068 } 069 070 public DefaultContextLoadTimeWeaver(ClassLoader beanClassLoader) { 071 setBeanClassLoader(beanClassLoader); 072 } 073 074 075 @Override 076 public void setBeanClassLoader(ClassLoader classLoader) { 077 LoadTimeWeaver serverSpecificLoadTimeWeaver = createServerSpecificLoadTimeWeaver(classLoader); 078 if (serverSpecificLoadTimeWeaver != null) { 079 if (logger.isDebugEnabled()) { 080 logger.debug("Determined server-specific load-time weaver: " + 081 serverSpecificLoadTimeWeaver.getClass().getName()); 082 } 083 this.loadTimeWeaver = serverSpecificLoadTimeWeaver; 084 } 085 else if (InstrumentationLoadTimeWeaver.isInstrumentationAvailable()) { 086 logger.debug("Found Spring's JVM agent for instrumentation"); 087 this.loadTimeWeaver = new InstrumentationLoadTimeWeaver(classLoader); 088 } 089 else { 090 try { 091 this.loadTimeWeaver = new ReflectiveLoadTimeWeaver(classLoader); 092 if (logger.isDebugEnabled()) { 093 logger.debug("Using reflective load-time weaver for class loader: " + 094 this.loadTimeWeaver.getInstrumentableClassLoader().getClass().getName()); 095 } 096 } 097 catch (IllegalStateException ex) { 098 throw new IllegalStateException(ex.getMessage() + " Specify a custom LoadTimeWeaver or start your " + 099 "Java virtual machine with Spring's agent: -javaagent:spring-instrument-{version}.jar"); 100 } 101 } 102 } 103 104 /* 105 * This method never fails, allowing to try other possible ways to use an 106 * server-agnostic weaver. This non-failure logic is required since 107 * determining a load-time weaver based on the ClassLoader name alone may 108 * legitimately fail due to other mismatches. 109 */ 110 @Nullable 111 protected LoadTimeWeaver createServerSpecificLoadTimeWeaver(ClassLoader classLoader) { 112 String name = classLoader.getClass().getName(); 113 try { 114 if (name.startsWith("org.apache.catalina")) { 115 return new TomcatLoadTimeWeaver(classLoader); 116 } 117 else if (name.startsWith("org.glassfish")) { 118 return new GlassFishLoadTimeWeaver(classLoader); 119 } 120 else if (name.startsWith("org.jboss.modules")) { 121 return new JBossLoadTimeWeaver(classLoader); 122 } 123 else if (name.startsWith("com.ibm.ws.classloader")) { 124 return new WebSphereLoadTimeWeaver(classLoader); 125 } 126 else if (name.startsWith("weblogic")) { 127 return new WebLogicLoadTimeWeaver(classLoader); 128 } 129 } 130 catch (Exception ex) { 131 if (logger.isInfoEnabled()) { 132 logger.info("Could not obtain server-specific LoadTimeWeaver: " + ex.getMessage()); 133 } 134 } 135 return null; 136 } 137 138 @Override 139 public void destroy() { 140 if (this.loadTimeWeaver instanceof InstrumentationLoadTimeWeaver) { 141 if (logger.isDebugEnabled()) { 142 logger.debug("Removing all registered transformers for class loader: " + 143 this.loadTimeWeaver.getInstrumentableClassLoader().getClass().getName()); 144 } 145 ((InstrumentationLoadTimeWeaver) this.loadTimeWeaver).removeTransformers(); 146 } 147 } 148 149 150 @Override 151 public void addTransformer(ClassFileTransformer transformer) { 152 Assert.state(this.loadTimeWeaver != null, "Not initialized"); 153 this.loadTimeWeaver.addTransformer(transformer); 154 } 155 156 @Override 157 public ClassLoader getInstrumentableClassLoader() { 158 Assert.state(this.loadTimeWeaver != null, "Not initialized"); 159 return this.loadTimeWeaver.getInstrumentableClassLoader(); 160 } 161 162 @Override 163 public ClassLoader getThrowawayClassLoader() { 164 Assert.state(this.loadTimeWeaver != null, "Not initialized"); 165 return this.loadTimeWeaver.getThrowawayClassLoader(); 166 } 167 168}