net.vidageek.mirror.reflect.DefaultAnnotationHandler Maven / Gradle / Ivy

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package net.vidageek.mirror.reflect;

import java.lang.annotation.Annotation;

import net.vidageek.mirror.dsl.Mirror;
import net.vidageek.mirror.provider.ReflectionProvider;
import net.vidageek.mirror.reflect.dsl.AnnotationHandler;
import net.vidageek.mirror.reflect.dsl.MethodAnnotationHandler;

/**
 * This class is responsible for choosing where to reflect a single annotation.
 * 
 * @author dnfeitosa
 */
public final class DefaultAnnotationHandler implements AnnotationHandler {

	private final Class clazz;

	private final Class annotation;

	private final ReflectionProvider provider;

	public DefaultAnnotationHandler(final ReflectionProvider provider, final Class clazz, final Class annotation) {
		if (clazz == null) {
			throw new IllegalArgumentException("Argument clazz cannot be null.");
		}
		if (annotation == null) {
			throw new IllegalArgumentException("Argument annotation cannot be null.");
		}
		this.provider = provider;
		this.clazz = clazz;
		this.annotation = annotation;
	}

	public T atField(final String fieldName) {
		if ((fieldName == null) || (fieldName.trim().length() == 0)) {
			throw new IllegalArgumentException("fieldName cannot be null or empty.");
		}
		return provider
				.getAnnotatedElementReflectionProvider(new Mirror(provider).on(clazz).reflect().field(fieldName))
				.getAnnotation(annotation);
	}

	@SuppressWarnings("unchecked")
	public MethodAnnotationHandler atMethod(final String methodName) {
		if ((methodName == null) || (methodName.trim().length() == 0)) {
			throw new IllegalArgumentException("methodName cannot be null or empty");
		}
		return new DefaultMethodAnnotationHandler(provider, clazz, methodName, annotation);
	}

	public T atClass() {
		return provider.getAnnotatedElementReflectionProvider(clazz).getAnnotation(annotation);
	}

}