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/* * Copyright 2002-2019 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.instrument.classloading.jboss; import java.lang.instrument.ClassFileTransformer; import java.lang.reflect.Field; import java.lang.reflect.Method; import org.springframework.instrument.classloading.LoadTimeWeaver; import org.springframework.instrument.classloading.SimpleThrowawayClassLoader; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.ClassUtils; import org.springframework.util.ReflectionUtils; /** * {@link LoadTimeWeaver} implementation for JBoss's instrumentable ClassLoader. * Thanks to Ales Justin and Marius Bogoevici for the initial prototype. * * <p>As of Spring Framework 5.0, this weaver supports WildFly 8+. * As of Spring Framework 5.1.5, it also supports WildFly 13+. * * @author Costin Leau * @author Juergen Hoeller * @since 3.0 */ public class JBossLoadTimeWeaver implements LoadTimeWeaver { private static final String DELEGATING_TRANSFORMER_CLASS_NAME = "org.jboss.as.server.deployment.module.DelegatingClassFileTransformer"; private static final String WRAPPER_TRANSFORMER_CLASS_NAME = "org.jboss.modules.JLIClassTransformer"; private final ClassLoader classLoader; private final Object delegatingTransformer; private final Method addTransformer; /** * Create a new instance of the {@link JBossLoadTimeWeaver} class using * the default {@link ClassLoader class loader}. * @see org.springframework.util.ClassUtils#getDefaultClassLoader() */ public JBossLoadTimeWeaver() { this(ClassUtils.getDefaultClassLoader()); } /** * Create a new instance of the {@link JBossLoadTimeWeaver} class using * the supplied {@link ClassLoader}. * @param classLoader the {@code ClassLoader} to delegate to for weaving */ public JBossLoadTimeWeaver(@Nullable ClassLoader classLoader) { Assert.notNull(classLoader, "ClassLoader must not be null"); this.classLoader = classLoader; try { Field transformer = ReflectionUtils.findField(classLoader.getClass(), "transformer"); if (transformer == null) { throw new IllegalArgumentException("Could not find 'transformer' field on JBoss ClassLoader: " + classLoader.getClass().getName()); } transformer.setAccessible(true); Object suggestedTransformer = transformer.get(classLoader); if (suggestedTransformer.getClass().getName().equals(WRAPPER_TRANSFORMER_CLASS_NAME)) { Field wrappedTransformer = ReflectionUtils.findField(suggestedTransformer.getClass(), "transformer"); if (wrappedTransformer == null) { throw new IllegalArgumentException( "Could not find 'transformer' field on JBoss JLIClassTransformer: " + suggestedTransformer.getClass().getName()); } wrappedTransformer.setAccessible(true); suggestedTransformer = wrappedTransformer.get(suggestedTransformer); } if (!suggestedTransformer.getClass().getName().equals(DELEGATING_TRANSFORMER_CLASS_NAME)) { throw new IllegalStateException( "Transformer not of the expected type DelegatingClassFileTransformer: " + suggestedTransformer.getClass().getName()); } this.delegatingTransformer = suggestedTransformer; Method addTransformer = ReflectionUtils.findMethod(this.delegatingTransformer.getClass(), "addTransformer", ClassFileTransformer.class); if (addTransformer == null) { throw new IllegalArgumentException( "Could not find 'addTransformer' method on JBoss DelegatingClassFileTransformer: " + this.delegatingTransformer.getClass().getName()); } addTransformer.setAccessible(true); this.addTransformer = addTransformer; } catch (Throwable ex) { throw new IllegalStateException("Could not initialize JBoss LoadTimeWeaver", ex); } } @Override public void addTransformer(ClassFileTransformer transformer) { try { this.addTransformer.invoke(this.delegatingTransformer, transformer); } catch (Throwable ex) { throw new IllegalStateException("Could not add transformer on JBoss ClassLoader: " + this.classLoader, ex); } } @Override public ClassLoader getInstrumentableClassLoader() { return this.classLoader; } @Override public ClassLoader getThrowawayClassLoader() { return new SimpleThrowawayClassLoader(getInstrumentableClassLoader()); } }