com.github.nill14.utils.init.impl.AnnotationLifecycleInitializer Maven / Gradle / Ivy

Go to download
package com.github.nill14.utils.init.impl;

import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Optional;
import java.util.stream.Stream;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

import com.github.nill14.utils.init.api.ILazyPojo;
import com.github.nill14.utils.init.api.IPojoFactory;
import com.github.nill14.utils.init.api.IPojoInitializer;

@SuppressWarnings("serial")
public class AnnotationLifecycleInitializer implements IPojoInitializer {

	@Override
	public void init(ILazyPojo lazyPojo, IPojoFactory pojoFactory, Object instance) {
		doPostConstruct(instance);
	}

	@Override
	public void destroy(ILazyPojo lazyPojo, IPojoFactory pojoFactory, Object instance) {
		doPreDestroy(instance);
		
	}
	
	private Optional getMethod(Object instance, Class annotationClass) {
		Method[] methods = instance.getClass().getDeclaredMethods();
		return Stream.of(methods)
				.filter(m -> !Modifier.isStatic(m.getModifiers()))
				.filter(m -> m.isAnnotationPresent(annotationClass))
				.findFirst();
	}	
	
	private Object invoke(Object instance, Method method, Object[] args) {
		try {
			return method.invoke(instance, args);
		} catch (IllegalAccessException | IllegalArgumentException e) {
			throw new RuntimeException(e);
		} catch (InvocationTargetException e) {
			throw new RuntimeException(e.getTargetException());
		}
	}
	
	private void doPreDestroy(Object instance) {
		Optional optional = getMethod(instance, PreDestroy.class);
		if (optional.isPresent()) {
			Method method = optional.get();
			method.setAccessible(true);
			invoke(instance, method, null);
		}
	}

	private void doPostConstruct(Object instance) {
		Optional optional = getMethod(instance, PostConstruct.class);
		if (optional.isPresent()) {
			Method method = optional.get();
			method.setAccessible(true);
			invoke(instance, method, null);
		}
	}

}