ClassFileTransformer for capturing GeneratedClosure byte code

GeneratedClosureClassFileTransformer.java

	
	/**
	 * {@inheritDoc}
	 * @see java.lang.instrument.ClassFileTransformer#transform(java.lang.ClassLoader, java.lang.String, java.lang.Class, java.security.ProtectionDomain, byte[])
	 */
	@Override
	public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException {
		byte[] bytecode = classfileBuffer;
		if(classBeingRedefined==null) {
			if(loader instanceof GroovyClassLoader && isGeneratedClosure(bytecode)) {
				put(className, loader, bytecode);
				log.log("Class Load Stored [" , bytecode.length , "] Bytes for deferred class [" , className , "]");
			}
		} else {
			if(GeneratedClosure.class.isAssignableFrom(classBeingRedefined)) {
				put(classBeingRedefined, bytecode);
				log.log("Class Retransform Stored [" , bytecode.length , "] Bytes for deferred class [" , className , "]");				
			}			
		}
		return bytecode;
	}

	/**
	 * Determines if the passed bytecode represents a class that implements {@link GeneratedClosure}.
	 * @param bytecode The byte array
	 * @return true if the bytecode represents a class that implements {@link GeneratedClosure}, false otherwise.
	 */
	protected boolean isGeneratedClosure(byte[] bytecode) {
		try {
			for(String iface: new ClassReader(bytecode).getInterfaces()) {
				if(generatedClosureName.equals(iface)) return true;
			}
			return false;
		} catch (Exception e) {
			return false;
		}
	}