scouter.javassist.Translator Maven / Gradle / Ivy
/*
* Javassist, a Java-bytecode translator toolkit.
* Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. Alternatively, the contents of this file may be used under
* the terms of the GNU Lesser General Public License Version 2.1 or later,
* or the Apache License Version 2.0.
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*/
package scouter.javassist;
/**
* An observer of Loader.
* The users can define a class implementing this
* interface and attach an instance of that class to a
* Loader object so that it can translate a class file
* when the class file is loaded into the JVM.
*
* @see Loader#addTranslator(ClassPool, Translator)
*/
public interface Translator {
/**
* Is invoked by a Loader for initialization
* when the object is attached to the Loader object.
* This method can be used for getting (for caching) some
* CtClass objects that will be accessed
* in onLoad() in Translator.
*
* @param pool the ClassPool that this translator
* should use.
* @see Loader
* @throws NotFoundException if a CtClass cannot be found.
* @throws CannotCompileException if the initialization by this method
* fails.
*/
void start(ClassPool pool)
throws NotFoundException, CannotCompileException;
/**
* Is invoked by a Loader for notifying that
* a class is loaded. The Loader calls
*
*
* pool.get(classname).toBytecode()
*
* to read the class file after onLoad() returns.
*
* classname may be the name of a class
* that has not been created yet.
* If so, onLoad() must create that class so that
* the Loader can read it after onLoad()
* returns.
*
* @param pool the ClassPool that this translator
* should use.
* @param classname the name of the class being loaded.
* @see Loader
* @throws NotFoundException if a CtClass cannot be found.
* @throws CannotCompileException if the code transformation
* by this method fails.
*/
void onLoad(ClassPool pool, String classname)
throws NotFoundException, CannotCompileException;
}