/**
* EasyBeans
* Copyright (C) 2007 Bull S.A.S.
* Contact: easybeans@ow2.org
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* --------------------------------------------------------------------------
* $Id: GenerateClass.java 5369 2010-02-24 14:58:19Z benoitf $
* --------------------------------------------------------------------------
*/
package org.ow2.easybeans.component.smartclient.test;
import org.ow2.easybeans.asm.ClassWriter;
import org.ow2.easybeans.asm.MethodVisitor;
import org.ow2.easybeans.asm.Opcodes;
/**
* Allow to generate dynamically a class.
* @author Florent BENOIT
*/
public final class GenerateClass implements Opcodes {
/**
* Utility class, no public constructor.
*/
private GenerateClass() {
}
/**
* Gets the bytecode for the given generated classname and the content of
* the hello() method.
* @param className the name of the class to generate
* @param helloWorldString the content that hello() method will return
* @return the bytecode
* @throws Exception if bytecode can't be built
*/
public static byte[] getByteForClass(final String className, final String helloWorldString) throws Exception {
ClassWriter cw = new ClassWriter(0);
MethodVisitor mv;
cw.visit(V1_5, ACC_PUBLIC + ACC_SUPER, className, null, "java/lang/Object", null);
// Constructor
mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
mv.visitCode();
mv.visitVarInsn(ALOAD, 0);
mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
mv.visitInsn(RETURN);
mv.visitMaxs(1, 1);
mv.visitEnd();
// hello method
mv = cw.visitMethod(ACC_PUBLIC, "hello", "()Ljava/lang/String;", null, null);
mv.visitCode();
mv.visitLdcInsn(helloWorldString);
mv.visitInsn(ARETURN);
mv.visitMaxs(1, 1);
mv.visitEnd();
cw.visitEnd();
return cw.toByteArray();
}
}