Side effects of bytebuddy rebasing to weaving process? about byte-buddy

[raphw]

Byte Buddy implements an immutable builder, there should be no side effects. Maybe the weaver fails as you refer to the loaded MyPrinter class?

You can use a TypePool to describe s class from class bytes.

[rage5474]

Thanks for the hint. This code is working fine for me. With this service it is even possible to modify not exported classes without modifying anything in the manifest. This is really great, because I can modify cross-cutting things in OSGi without using java agents.

@Component(immediate = true)
public class WeavingHookService implements WeavingHook {

  private static final String CLASS_TO_MODIFY = "my.waevinghook.example.internal.MyPrinter";

  @Override
  public void weave(WovenClass wovenClass) {

    if (wovenClass.getClassName().equals(CLASS_TO_MODIFY)) {
      try {
        byte[] originalBytes = wovenClass.getBytes();

        ClassFileLocator locator = ClassFileLocator.Simple
            .of(wovenClass.getClassName(),
                originalBytes);

        Unloaded<Object> newPrinter = new ByteBuddy()
            .rebase(TypePool.Default.of(wovenClass.getBundleWiring().getClassLoader())
                .describe(
                CLASS_TO_MODIFY).resolve(),
                locator)
            .method(ElementMatchers.named("getName"))
            .intercept(FixedValue.value("Raphael"))
            .make();

        wovenClass.setBytes(newPrinter.getBytes());
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
  }
}