Class remapper ASM/Byte Buddy example

Bar.java

package x;

public class Bar extends Foo {

    @Override
    public void m() {
        System.out.println("bar");
    }
}

Demo.java

import static net.bytebuddy.matcher.ElementMatchers.named;

import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.commons.ClassRemapper;
import org.objectweb.asm.commons.SimpleRemapper;

import net.bytebuddy.agent.ByteBuddyAgent;
import net.bytebuddy.agent.builder.AgentBuilder;
import net.bytebuddy.asm.AsmVisitorWrapper;
import net.bytebuddy.description.field.FieldDescription;
import net.bytebuddy.description.field.FieldList;
import net.bytebuddy.description.method.MethodList;
import net.bytebuddy.description.type.TypeDescription;
import net.bytebuddy.dynamic.DynamicType;
import net.bytebuddy.implementation.Implementation;
import net.bytebuddy.pool.TypePool;
import net.bytebuddy.utility.JavaModule;
import x.Qux;

class Demo {
    public static void main(String[] args) {
        new AgentBuilder.Default()
            .with(AgentBuilder.Listener.StreamWriting.toSystemError().withTransformationsOnly())
            .with(AgentBuilder.RedefinitionStrategy.RETRANSFORMATION)
            .type(named("x.Qux"))
            .transform((builder, typeDescription, classLoader, module) -> builder.visit(new AsmVisitorWrapper.AbstractBase() {
              public ClassVisitor wrap(
                TypeDescription instrumentedType, ClassVisitor classVisitor,
                Implementation.Context implementationContext, TypePool typePool,
                FieldList<FieldDescription.InDefinedShape> fields, MethodList<?> methods,
                int writerFlags, int readerFlags
              ) {
                return new ClassRemapper(classVisitor, new SimpleRemapper("x/Foo", "x/Bar"));
              }
            }).installOn(ByteBuddyAgent.install());

        new Qux().demo();
    }
}

Foo.java

package x;

public class Foo {

    public void m() {
        System.out.println("foo");
    }
}

Qux.java

package x;

public class Qux {

    public void demo() {
        new Foo().m();
    }
}

Glad to have found this example, thanks.