org.glassfish.hk2.api.AnnotationLiteral Maven / Gradle / Ivy
/*
* Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.hk2.api;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Arrays;
/**
* Supports inline instantiation of annotation type instances.
*
* An instance of an annotation type may be obtained by subclassing
* AnnotationLiteral.
*
*
* public abstract class PayByQualifier
* extends AnnotationLiteral<PayBy>
* implements PayBy {}
*
*
*
* An extension of AnnotationLiteral must do two things:
* - Must have the target annotation as its generic type
* - Must implement the target type
*
*
* In particular, in-line anonymous extensions of AnnotationLiteral will not
* work because in-line anonymous extensions of AnnotationLiteral cannot implement
* the target annotation
*
* @author jwells
*
* @param the annotation type
*/
public abstract class AnnotationLiteral implements Annotation, Serializable {
/**
* For serialization
*/
private static final long serialVersionUID = -3645430766814376616L;
private transient Class annotationType;
private transient Method[] members;
protected AnnotationLiteral() {
Class thisClass = this.getClass();
boolean foundAnnotation = false;
for (Class iClass : thisClass.getInterfaces()) {
if (iClass.isAnnotation()) {
foundAnnotation = true;
break;
}
}
if (!foundAnnotation) {
throw new IllegalStateException("The subclass " + thisClass.getName() + " of AnnotationLiteral must implement an Annotation");
}
}
private Method[] getMembers()
{
if (members==null) {
members = AccessController.doPrivileged(new PrivilegedAction() {
@Override
public Method[] run() {
return annotationType().getDeclaredMethods();
}
});
if ( members.length>0 && !annotationType().isAssignableFrom(this.getClass()) ) {
throw new RuntimeException(getClass() + " does not implement the annotation type with members " + annotationType().getName());
}
}
return members;
}
private static Class getAnnotationLiteralSubclass(Class clazz)
{
Class superclass = clazz.getSuperclass();
if (superclass.equals(AnnotationLiteral.class))
{
return clazz;
}
else if (superclass.equals(Object.class))
{
return null;
}
else
{
return (getAnnotationLiteralSubclass(superclass));
}
}
@SuppressWarnings("unchecked")
private static Class getTypeParameter(Class annotationLiteralSuperclass)
{
Type type = annotationLiteralSuperclass.getGenericSuperclass();
if (type instanceof ParameterizedType)
{
ParameterizedType parameterizedType = (ParameterizedType) type;
if (parameterizedType.getActualTypeArguments().length == 1)
{
return (Class) parameterizedType
.getActualTypeArguments()[0];
}
}
return null;
}
public Class annotationType()
{
if (annotationType==null)
{
Class annotationLiteralSubclass = getAnnotationLiteralSubclass(this.getClass());
if (annotationLiteralSubclass == null)
{
throw new RuntimeException(getClass() + "is not a subclass of AnnotationLiteral");
}
annotationType = getTypeParameter(annotationLiteralSubclass);
if (annotationType == null)
{
throw new RuntimeException(getClass() + " does not specify the type parameter T of AnnotationLiteral");
}
}
return annotationType;
}
@Override
public boolean equals(Object other)
{
if (other instanceof Annotation)
{
Annotation that = (Annotation) other;
if (this.annotationType().equals(that.annotationType()))
{
for (Method member : getMembers())
{
Object thisValue = invoke(member, this);
Object thatValue = invoke(member, that);
if (thisValue instanceof byte[] && thatValue instanceof byte[])
{
if ( !Arrays.equals((byte[])thisValue, (byte[])thatValue) ) return false;
}
else if (thisValue instanceof short[] && thatValue instanceof short[])
{
if ( !Arrays.equals((short[])thisValue, (short[])thatValue) ) return false;
}
else if (thisValue instanceof int[] && thatValue instanceof int[])
{
if ( !Arrays.equals((int[])thisValue, (int[])thatValue) ) return false;
}
else if (thisValue instanceof long[] && thatValue instanceof long[])
{
if ( !Arrays.equals((long[])thisValue, (long[])thatValue) ) return false;
}
else if (thisValue instanceof float[] && thatValue instanceof float[])
{
if ( !Arrays.equals((float[])thisValue, (float[])thatValue) ) return false;
}
else if (thisValue instanceof double[] && thatValue instanceof double[])
{
if ( !Arrays.equals((double[])thisValue, (double[])thatValue) ) return false;
}
else if (thisValue instanceof char[] && thatValue instanceof char[])
{
if ( !Arrays.equals((char[])thisValue, (char[])thatValue) ) return false;
}
else if (thisValue instanceof boolean[] && thatValue instanceof boolean[])
{
if ( !Arrays.equals((boolean[])thisValue, (boolean[])thatValue) ) return false;
}
else if (thisValue instanceof Object[] && thatValue instanceof Object[])
{
if ( !Arrays.equals((Object[])thisValue, (Object[])thatValue) ) return false;
}
else
{
if (!thisValue.equals(thatValue)) return false;
}
}
return true;
}
}
return false;
}
@Override
public int hashCode()
{
int hashCode = 0;
for (Method member: getMembers())
{
int memberNameHashCode = 127 * member.getName().hashCode();
Object value = invoke(member, this);
int memberValueHashCode;
if (value instanceof boolean[])
{
memberValueHashCode = Arrays.hashCode((boolean[]) value);
}
else if (value instanceof short[])
{
memberValueHashCode = Arrays.hashCode((short[]) value);
}
else if (value instanceof int[])
{
memberValueHashCode = Arrays.hashCode((int[]) value);
}
else if (value instanceof long[])
{
memberValueHashCode = Arrays.hashCode((long[]) value);
}
else if (value instanceof float[])
{
memberValueHashCode = Arrays.hashCode((float[]) value);
}
else if (value instanceof double[])
{
memberValueHashCode = Arrays.hashCode((double[]) value);
}
else if (value instanceof byte[])
{
memberValueHashCode = Arrays.hashCode((byte[]) value);
}
else if (value instanceof char[])
{
memberValueHashCode = Arrays.hashCode((char[]) value);
}
else if (value instanceof Object[])
{
memberValueHashCode = Arrays.hashCode((Object[]) value);
}
else
{
memberValueHashCode = value.hashCode();
}
hashCode += memberNameHashCode ^ memberValueHashCode;
}
return hashCode;
}
private static void setAccessible(final AccessibleObject ao) {
AccessController.doPrivileged(new PrivilegedAction