public byte[] transform(
      ClassLoader loader,
      String className,
      Class<?> classBeingRedefined,
      ProtectionDomain protectionDomain,
      byte[] classfileBuffer)
      throws IllegalClassFormatException {
    if (infos.isEmpty()) {
      return null;
    }
    String convertedClassName = className.replace('/', '.');
    SingleTableInheritanceInfo key = new SingleTableInheritanceInfo();
    key.setClassName(convertedClassName);
    int pos = infos.indexOf(key);
    if (pos >= 0) {
      try {
        if (LOG.isDebugEnabled()) {
          LOG.debug("Converting " + convertedClassName + " to a SingleTable inheritance strategy.");
        }
        SingleTableInheritanceInfo myInfo = infos.get(pos);
        ClassFile classFile =
            new ClassFile(new DataInputStream(new ByteArrayInputStream(classfileBuffer)));
        ConstPool constantPool = classFile.getConstPool();
        AnnotationsAttribute annotationsAttribute =
            new AnnotationsAttribute(constantPool, AnnotationsAttribute.visibleTag);
        List<?> attributes = classFile.getAttributes();
        Iterator<?> itr = attributes.iterator();
        while (itr.hasNext()) {
          Object object = itr.next();
          if (AnnotationsAttribute.class.isAssignableFrom(object.getClass())) {
            AnnotationsAttribute attr = (AnnotationsAttribute) object;
            Annotation[] items = attr.getAnnotations();
            for (Annotation annotation : items) {
              String typeName = annotation.getTypeName();
              if (!typeName.equals(Inheritance.class.getName())
                  && ((myInfo.getDiscriminatorName() == null
                          && !typeName.equals(Table.class.getName()))
                      || myInfo.getDiscriminatorName() != null)) {
                annotationsAttribute.addAnnotation(annotation);
              }
            }
            itr.remove();
          }
        }
        Annotation inheritance = new Annotation(Inheritance.class.getName(), constantPool);
        ClassPool pool = ClassPool.getDefault();
        pool.importPackage("javax.persistence");
        pool.importPackage("java.lang");
        EnumMemberValue strategy =
            (EnumMemberValue)
                Annotation.createMemberValue(constantPool, pool.makeClass("InheritanceType"));
        strategy.setType(InheritanceType.class.getName());
        strategy.setValue(InheritanceType.SINGLE_TABLE.name());
        inheritance.addMemberValue("strategy", strategy);
        annotationsAttribute.addAnnotation(inheritance);
        if (myInfo.getDiscriminatorName() != null) {
          Annotation discriminator =
              new Annotation(DiscriminatorColumn.class.getName(), constantPool);
          StringMemberValue name = new StringMemberValue(constantPool);
          name.setValue(myInfo.getDiscriminatorName());
          discriminator.addMemberValue("name", name);
          EnumMemberValue discriminatorType =
              (EnumMemberValue)
                  Annotation.createMemberValue(constantPool, pool.makeClass("DiscriminatorType"));
          discriminatorType.setType(DiscriminatorType.class.getName());
          discriminatorType.setValue(myInfo.getDiscriminatorType().name());
          discriminator.addMemberValue("discriminatorType", discriminatorType);
          IntegerMemberValue length = new IntegerMemberValue(constantPool);
          length.setValue(myInfo.getDiscriminatorLength());
          discriminator.addMemberValue("length", length);

          annotationsAttribute.addAnnotation(discriminator);
        }
        classFile.addAttribute(annotationsAttribute);
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        DataOutputStream os = new DataOutputStream(bos);
        classFile.write(os);
        os.close();

        return bos.toByteArray();
      } catch (Exception ex) {
        ex.printStackTrace();
        throw new IllegalClassFormatException(
            "Unable to convert "
                + convertedClassName
                + " to a SingleTable inheritance strategy: "
                + ex.getMessage());
      }
    } else {
      return null;
    }
  }
Esempio n. 2
0
 /** {@inheritDoc} */
 @Override
 protected void generate() {
   this.inheritance =
       InheritanceType.valueOf(
           this.getAttribute(ElementConstants.ATTR_STRATEGY, InheritanceType.SINGLE_TABLE.name()));
 }