com.sun.org.apache.bcel.internal.generic.MethodGen Java Examples

The following examples show how to use com.sun.org.apache.bcel.internal.generic.MethodGen. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.

Example #1

Source File: BCELifier.java From Bytecoder with Apache License 2.0

6 votes

@Override
public void visitMethod( final Method method ) {
    final MethodGen mg = new MethodGen(method, _clazz.getClassName(), _cp);
    _out.println("    InstructionList il = new InstructionList();");
    _out.println("    MethodGen method = new MethodGen("
            + printFlags(method.getAccessFlags(), FLAGS.METHOD) + ", "
            + printType(mg.getReturnType()) + ", "
            + printArgumentTypes(mg.getArgumentTypes()) + ", "
            + "new String[] { " + Utility.printArray(mg.getArgumentNames(), false, true)
            + " }, \"" + method.getName() + "\", \"" + _clazz.getClassName() + "\", il, _cp);");
    _out.println();
    final BCELFactory factory = new BCELFactory(mg, _out);
    factory.start();
    _out.println("    method.setMaxStack();");
    _out.println("    method.setMaxLocals();");
    _out.println("    _cg.addMethod(method.getMethod());");
    _out.println("    il.dispose();");
}

Example #2

Source File: Bug8003147Test.java From openjdk-jdk9 with GNU General Public License v2.0

5 votes

@Test
public void test() throws Exception {
    // Note: com.sun.org.apache.bcel.internal.classfile.JavaClass doesn't
    // support InvokeDynamic, so can't use lambda, also can't use string1 +
    // string2, because javac will generate a dynamic call where invoking
    // string1.concat(string2), so create a separate Bug8003147TestClass
    JAXPTestUtilities.tryRunWithTmpPermission(() -> {
        String classfile = getSystemProperty("test.classes") + "/parsers/Bug8003147TestClass.class";
        JavaClass jc = new ClassParser(classfile).parse();

        // rename class
        ConstantPool cp = jc.getConstantPool();
        int cpIndex = ((ConstantClass) cp.getConstant(jc.getClassNameIndex())).getNameIndex();
        cp.setConstant(cpIndex, new ConstantUtf8("parsers/Bug8003147TestClassPrime"));
        ClassGen gen = new ClassGen(jc);
        Method[] methods = jc.getMethods();
        int index;
        for (index = 0; index < methods.length; index++) {
            if (methods[index].getName().equals("doSomething")) {
                break;
            }
        }
        Method m = methods[index];
        MethodGen mg = new MethodGen(m, gen.getClassName(), gen.getConstantPool());
        gen.replaceMethod(m, mg.getMethod());
        String path = classfile.replace("Bug8003147TestClass", "Bug8003147TestClassPrime");
        gen.getJavaClass().dump(new FileOutputStream(path));

        try {
            Class.forName("parsers.Bug8003147TestClassPrime");
        } catch (ClassFormatError cfe) {
            cfe.printStackTrace();
            Assert.fail("modified version of class does not pass verification");
        }
    }, new FilePermission(getSystemProperty("test.classes") + "/-", "read,write"));
}

Example #3

Source File: BCELFactory.java From Bytecoder with Apache License 2.0

4 votes

BCELFactory(final MethodGen mg, final PrintWriter out) {
    _mg = mg;
    _cp = mg.getConstantPool();
    _out = out;
}