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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.transaction.interceptor; import java.lang.reflect.Method; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.factory.BeanClassLoaderAware; import org.springframework.beans.factory.InitializingBean; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.ClassUtils; import org.springframework.util.ObjectUtils; import org.springframework.util.PatternMatchUtils; /** * Simple {@link TransactionAttributeSource} implementation that * allows attributes to be stored per method in a {@link Map}. * * @author Rod Johnson * @author Juergen Hoeller * @since 24.04.2003 * @see #isMatch * @see NameMatchTransactionAttributeSource */ public class MethodMapTransactionAttributeSource implements TransactionAttributeSource, BeanClassLoaderAware, InitializingBean { /** Logger available to subclasses. */ protected final Log logger = LogFactory.getLog(getClass()); /** Map from method name to attribute value. */ @Nullable private Map<String, TransactionAttribute> methodMap; @Nullable private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader(); private boolean eagerlyInitialized = false; private boolean initialized = false; /** Map from Method to TransactionAttribute. */ private final Map<Method, TransactionAttribute> transactionAttributeMap = new HashMap<>(); /** Map from Method to name pattern used for registration. */ private final Map<Method, String> methodNameMap = new HashMap<>(); /** * Set a name/attribute map, consisting of "FQCN.method" method names * (e.g. "com.mycompany.mycode.MyClass.myMethod") and * {@link TransactionAttribute} instances (or Strings to be converted * to {@code TransactionAttribute} instances). * <p>Intended for configuration via setter injection, typically within * a Spring bean factory. Relies on {@link #afterPropertiesSet()} * being called afterwards. * @param methodMap said {@link Map} from method name to attribute value * @see TransactionAttribute * @see TransactionAttributeEditor */ public void setMethodMap(Map<String, TransactionAttribute> methodMap) { this.methodMap = methodMap; } @Override public void setBeanClassLoader(ClassLoader beanClassLoader) { this.beanClassLoader = beanClassLoader; } /** * Eagerly initializes the specified * {@link #setMethodMap(java.util.Map) "methodMap"}, if any. * @see #initMethodMap(java.util.Map) */ @Override public void afterPropertiesSet() { initMethodMap(this.methodMap); this.eagerlyInitialized = true; this.initialized = true; } /** * Initialize the specified {@link #setMethodMap(java.util.Map) "methodMap"}, if any. * @param methodMap a Map from method names to {@code TransactionAttribute} instances * @see #setMethodMap */ protected void initMethodMap(@Nullable Map<String, TransactionAttribute> methodMap) { if (methodMap != null) { methodMap.forEach(this::addTransactionalMethod); } } /** * Add an attribute for a transactional method. * <p>Method names can end or start with "*" for matching multiple methods. * @param name class and method name, separated by a dot * @param attr attribute associated with the method * @throws IllegalArgumentException in case of an invalid name */ public void addTransactionalMethod(String name, TransactionAttribute attr) { Assert.notNull(name, "Name must not be null"); int lastDotIndex = name.lastIndexOf('.'); if (lastDotIndex == -1) { throw new IllegalArgumentException( "'" + name + "' is not a valid method name: format is FQN.methodName"); } String className = name.substring(0, lastDotIndex); String methodName = name.substring(lastDotIndex + 1); Class<?> clazz = ClassUtils.resolveClassName(className, this.beanClassLoader); addTransactionalMethod(clazz, methodName, attr); } /** * Add an attribute for a transactional method. * Method names can end or start with "*" for matching multiple methods. * @param clazz target interface or class * @param mappedName mapped method name * @param attr attribute associated with the method */ public void addTransactionalMethod(Class<?> clazz, String mappedName, TransactionAttribute attr) { Assert.notNull(clazz, "Class must not be null"); Assert.notNull(mappedName, "Mapped name must not be null"); String name = clazz.getName() + '.' + mappedName; Method[] methods = clazz.getDeclaredMethods(); List<Method> matchingMethods = new ArrayList<>(); for (Method method : methods) { if (isMatch(method.getName(), mappedName)) { matchingMethods.add(method); } } if (matchingMethods.isEmpty()) { throw new IllegalArgumentException( "Could not find method '" + mappedName + "' on class [" + clazz.getName() + "]"); } // Register all matching methods for (Method method : matchingMethods) { String regMethodName = this.methodNameMap.get(method); if (regMethodName == null || (!regMethodName.equals(name) && regMethodName.length() <= name.length())) { // No already registered method name, or more specific // method name specification now -> (re-)register method. if (logger.isDebugEnabled() && regMethodName != null) { logger.debug("Replacing attribute for transactional method [" + method + "]: current name '" + name + "' is more specific than '" + regMethodName + "'"); } this.methodNameMap.put(method, name); addTransactionalMethod(method, attr); } else { if (logger.isDebugEnabled()) { logger.debug("Keeping attribute for transactional method [" + method + "]: current name '" + name + "' is not more specific than '" + regMethodName + "'"); } } } } /** * Add an attribute for a transactional method. * @param method the method * @param attr attribute associated with the method */ public void addTransactionalMethod(Method method, TransactionAttribute attr) { Assert.notNull(method, "Method must not be null"); Assert.notNull(attr, "TransactionAttribute must not be null"); if (logger.isDebugEnabled()) { logger.debug("Adding transactional method [" + method + "] with attribute [" + attr + "]"); } this.transactionAttributeMap.put(method, attr); } /** * Return if the given method name matches the mapped name. * <p>The default implementation checks for "xxx*", "*xxx" and "*xxx*" * matches, as well as direct equality. * @param methodName the method name of the class * @param mappedName the name in the descriptor * @return if the names match * @see org.springframework.util.PatternMatchUtils#simpleMatch(String, String) */ protected boolean isMatch(String methodName, String mappedName) { return PatternMatchUtils.simpleMatch(mappedName, methodName); } @Override @Nullable public TransactionAttribute getTransactionAttribute(Method method, @Nullable Class<?> targetClass) { if (this.eagerlyInitialized) { return this.transactionAttributeMap.get(method); } else { synchronized (this.transactionAttributeMap) { if (!this.initialized) { initMethodMap(this.methodMap); this.initialized = true; } return this.transactionAttributeMap.get(method); } } } @Override public boolean equals(@Nullable Object other) { if (this == other) { return true; } if (!(other instanceof MethodMapTransactionAttributeSource)) { return false; } MethodMapTransactionAttributeSource otherTas = (MethodMapTransactionAttributeSource) other; return ObjectUtils.nullSafeEquals(this.methodMap, otherTas.methodMap); } @Override public int hashCode() { return MethodMapTransactionAttributeSource.class.hashCode(); } @Override public String toString() { return getClass().getName() + ": " + this.methodMap; } }