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JSR 380's RI, Hibernate Validator version ${hibernate-validator.version} and its dependencies repackaged as OSGi bundle

There is a newer version: 5.1.0

/*
 * Hibernate Validator, declare and validate application constraints
 *
 * License: Apache License, Version 2.0
 * See the license.txt file in the root directory or .
 */
package org.hibernate.validator.internal.util.annotation;

import java.lang.annotation.Annotation;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Proxy;
import java.security.AccessController;
import java.security.PrivilegedAction;

import org.hibernate.validator.internal.util.privilegedactions.ConstructorInstance;
import org.hibernate.validator.internal.util.privilegedactions.GetClassLoader;
import org.hibernate.validator.internal.util.privilegedactions.GetDeclaredConstructor;

/**
 * Creates live annotations (actually {@link AnnotationProxy} instances) from {@code AnnotationDescriptor}s.
 *
 * @author Paolo Perrotta
 * @author Davide Marchignoli
 * @author Hardy Ferentschik
 * @see AnnotationProxy
 */
public class AnnotationFactory {

	private AnnotationFactory() {
	}

	public static  T create(AnnotationDescriptor descriptor) {
		@SuppressWarnings("unchecked")
		Class proxyClass = (Class) Proxy.getProxyClass(
				run( GetClassLoader.fromClass( descriptor.getType() ) ),
				descriptor.getType()
		);
		InvocationHandler handler = new AnnotationProxy( descriptor );
		try {
			return getProxyInstance( proxyClass, handler );
		}
		catch (RuntimeException e) {
			throw e;
		}
		catch (Exception e) {
			throw new RuntimeException( e );
		}
	}

	private static  T getProxyInstance(Class proxyClass, InvocationHandler handler) throws
			SecurityException, NoSuchMethodException, IllegalArgumentException, InstantiationException,
			IllegalAccessException, InvocationTargetException {
		final Constructor constructor = run( GetDeclaredConstructor.action(
				proxyClass,
				InvocationHandler.class
		) );
		return run( ConstructorInstance.action( constructor, handler ) );
	}

	/**
	 * Runs the given privileged action, using a privileged block if required.
	 * 
	 * NOTE: This must never be changed into a publicly available method to avoid execution of arbitrary
	 * privileged actions within HV's protection domain.
	 */
	private static  T run(PrivilegedAction action) {
		return System.getSecurityManager() != null ? AccessController.doPrivileged( action ) : action.run();
	}
}