| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 |
| * |
| * http://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.apache.openjpa.enhance; |
| |
| import java.lang.instrument.Instrumentation; |
| import java.security.AccessController; |
| import java.util.List; |
| |
| import org.apache.openjpa.conf.OpenJPAConfiguration; |
| import org.apache.openjpa.conf.OpenJPAConfigurationImpl; |
| import org.apache.openjpa.lib.conf.Configuration; |
| import org.apache.openjpa.lib.conf.Configurations; |
| import org.apache.openjpa.lib.log.Log; |
| import org.apache.openjpa.lib.util.J2DoPrivHelper; |
| import org.apache.openjpa.lib.util.Options; |
| import org.apache.openjpa.util.ClassResolver; |
| |
| /** |
| * <p> |
| * Java agent that makes persistent classes work with OpenJPA at runtime. This |
| * is achieved by either running the enhancer on the classes as they are loaded, |
| * or by redefining the classes on the fly. The agent is launched at JVM startup |
| * from the command line: |
| * </p> |
| * |
| * <p> |
| * <code>java -javaagent:openjpa.jar[=<options>]</code> The options string |
| * should be formatted as a OpenJPA plugin, and may contain any properties |
| * understood by the OpenJPA enhancer or any configuration properties. For |
| * example: |
| * </p> |
| * |
| * <p> |
| * <code>java -javaagent:openjpa.jar</code> |
| * </p> |
| * |
| * <p> |
| * By default, if specified, the agent runs the OpenJPA enhancer on all classes |
| * listed in the first persistence unit as they are loaded, and redefines all |
| * other persistent classes when they are encountered. To disable enhancement at |
| * class-load time and rely solely on the redefinition logic, set the |
| * ClassLoadEnhancement flag to false. To disable redefinition and rely solely |
| * on pre-deployment or class-load enhancement, set the RuntimeRedefinition flag |
| * to false. |
| * </p> |
| * |
| * <p> |
| * <code>java -javaagent:openjpa.jar=ClassLoadEnhancement=false</code> |
| * </p> |
| * |
| * @author Abe White |
| * @author Patrick Linskey |
| */ |
| public class PCEnhancerAgent { |
| |
| private static boolean loadAttempted = false; |
| private static boolean loadSuccessful = false; |
| private static boolean disableDynamicAgent = false; |
| |
| /** |
| * @return True if the Agent has ran successfully. False otherwise. |
| */ |
| public static synchronized boolean getLoadSuccessful() { |
| return loadSuccessful; |
| } |
| |
| public static void disableDynamicAgent(){ |
| disableDynamicAgent=true; |
| } |
| |
| /** |
| * @return True if the agent is loaded successfully |
| */ |
| public static synchronized boolean loadDynamicAgent(Log log) { |
| if (!loadAttempted && !disableDynamicAgent) { |
| Instrumentation inst = |
| InstrumentationFactory.getInstrumentation(log); |
| if (inst != null) { |
| premain("", inst); |
| return true; |
| } |
| // If we successfully get the Instrumentation, we will call premain |
| // where loadAttempted will be set to true. This case is the path |
| // where we were unable to get Instrumentation so we need to set the |
| // loadAttempted flag to true. We do this so we will only run |
| // through this code one time. |
| loadAttempted = true; |
| } |
| |
| return false; |
| } |
| |
| public static void premain(String args, Instrumentation inst) { |
| // If the enhancer has already completed, noop. This can happen |
| // if runtime enhancement is specified via javaagent, and |
| // openJPA tries to dynamically enhance. |
| // The agent will be disabled when running in an application |
| // server. |
| synchronized (PCEnhancerAgent.class) { |
| if (loadAttempted) { |
| return; |
| } |
| // See the comment in loadDynamicAgent as to why we set this to true |
| // in multiple places. |
| loadAttempted = true; |
| } |
| |
| Options opts = Configurations.parseProperties(args); |
| |
| if (opts.containsKey("ClassLoadEnhancement") || |
| opts.containsKey("classLoadEnhancement")) { |
| if (opts.getBooleanProperty( |
| "ClassLoadEnhancement", "classLoadEnhancement", true)) |
| registerClassLoadEnhancer(inst, opts); |
| } |
| else if (opts.containsKey("RuntimeEnhancement") || |
| opts.containsKey("runtimeEnhancement")) { |
| // Deprecated property setting |
| if (opts.getBooleanProperty( |
| "RuntimeEnhancement", "runtimeEnhancement", true)) |
| registerClassLoadEnhancer(inst, opts); |
| } else { |
| // if neither is set, then we should be turning it on. We need this |
| // logic instead of just a getBooleanProperty() because of the |
| // backwards-compat logic flow. |
| registerClassLoadEnhancer(inst, opts); |
| } |
| |
| if (opts.getBooleanProperty( |
| "RuntimeRedefinition", "runtimeRedefinition", true)) { |
| InstrumentationFactory.setInstrumentation(inst); |
| } else { |
| InstrumentationFactory.setDynamicallyInstallAgent(false); |
| } |
| loadSuccessful = true; |
| } |
| |
| private static void registerClassLoadEnhancer(Instrumentation inst, |
| Options opts) { |
| List<String> anchors = Configurations. |
| getFullyQualifiedAnchorsInPropertiesLocation(opts); |
| for (String a : anchors) { |
| Options clonedOptions = (Options) opts.clone(); |
| clonedOptions.setProperty("properties", a); |
| OpenJPAConfiguration conf = new OpenJPAConfigurationImpl(); |
| Configurations.populateConfiguration(conf, clonedOptions); |
| // don't allow connections |
| conf.setConnectionUserName(null); |
| conf.setConnectionPassword(null); |
| conf.setConnectionURL(null); |
| conf.setConnectionDriverName(null); |
| conf.setConnectionFactoryName(null); |
| // set single class resolver |
| final ClassLoader tmpLoader = AccessController |
| .doPrivileged(J2DoPrivHelper |
| .newTemporaryClassLoaderAction(AccessController |
| .doPrivileged(J2DoPrivHelper.getContextClassLoaderAction()) |
| )); |
| conf.setClassResolver(new ClassResolver() { |
| @Override |
| public ClassLoader getClassLoader(Class context, |
| ClassLoader env) { |
| return tmpLoader; |
| } |
| }); |
| conf.setReadOnly(Configuration.INIT_STATE_FREEZING); |
| conf.instantiateAll(); // avoid threading issues |
| |
| PCClassFileTransformer transformer = PCClassFileTransformer.newInstance |
| (conf.newMetaDataRepositoryInstance(), clonedOptions, |
| tmpLoader); |
| inst.addTransformer(transformer); |
| conf.close(); |
| } |
| } |
| } |