/*
* Hibernate Validator, declare and validate application constraints
*
* License: Apache License, Version 2.0
* See the license.txt file in the root directory or <http://www.apache.org/licenses/LICENSE-2.0>.
*/
package org.hibernate.validator.internal.util.annotationfactory;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Arrays;
import java.util.Collections;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
import org.hibernate.validator.internal.util.logging.Log;
import org.hibernate.validator.internal.util.logging.LoggerFactory;
import org.hibernate.validator.internal.util.privilegedactions.GetDeclaredMethod;
import org.hibernate.validator.internal.util.privilegedactions.GetDeclaredMethods;
import static org.hibernate.validator.internal.util.CollectionHelper.newHashMap;
/**
* A concrete implementation of <code>Annotation</code> that pretends it is a
* "real" source code annotation. It's also an <code>InvocationHandler</code>.
* <p>
* When you create an <code>AnnotationProxy</code>, you must initialize it
* with an <code>AnnotationDescriptor</code>.
* The adapter checks that the provided elements are the same elements defined
* in the annotation interface. However, it does <i>not</i> check that their
* values are the right type. If you omit an element, the adapter will use the
* default value for that element from the annotation interface, if it exists.
* If no default exists, it will throw an exception.
* </p>
*
* @author Paolo Perrotta
* @author Davide Marchignoli
* @author Gunnar Morling
* @see java.lang.annotation.Annotation
*/
class AnnotationProxy implements Annotation, InvocationHandler, Serializable {
private static final long serialVersionUID = 6907601010599429454L;
private static final Log log = LoggerFactory.make();
private final Class<? extends Annotation> annotationType;
private final Map<String, Object> values;
private final int hashCode;
AnnotationProxy(AnnotationDescriptor<?> descriptor) {
this.annotationType = descriptor.type();
values = Collections.unmodifiableMap( getAnnotationValues( descriptor ) );
this.hashCode = calculateHashCode();
}
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
if ( values.containsKey( method.getName() ) ) {
return values.get( method.getName() );
}
return method.invoke( this, args );
}
@Override
public Class<? extends Annotation> annotationType() {
return annotationType;
}
/**
* Performs an equality check as described in {@link Annotation#equals(Object)}.
*
* @param obj The object to compare
*
* @return Whether the given object is equal to this annotation proxy or not
*
* @see Annotation#equals(Object)
*/
@Override
public boolean equals(Object obj) {
if ( this == obj ) {
return true;
}
if ( obj == null ) {
return false;
}
if ( !annotationType.isInstance( obj ) ) {
return false;
}
Annotation other = annotationType.cast( obj );
//compare annotation member values
for ( Entry<String, Object> member : values.entrySet() ) {
Object value = member.getValue();
Object otherValue = getAnnotationMemberValue( other, member.getKey() );
if ( !areEqual( value, otherValue ) ) {
return false;
}
}
return true;
}
/**
* Calculates the hash code of this annotation proxy as described in
* {@link Annotation#hashCode()}.
*
* @return The hash code of this proxy.
*
* @see Annotation#hashCode()
*/
@Override
public int hashCode() {
return hashCode;
}
@Override
public String toString() {
StringBuilder result = new StringBuilder();
result.append( '@' ).append( annotationType.getName() ).append( '(' );
for ( String s : getRegisteredMethodsInAlphabeticalOrder() ) {
result.append( s ).append( '=' ).append( values.get( s ) ).append( ", " );
}
// remove last separator:
if ( values.size() > 0 ) {
result.delete( result.length() - 2, result.length() );
result.append( ")" );
}
else {
result.delete( result.length() - 1, result.length() );
}
return result.toString();
}
private Map<String, Object> getAnnotationValues(AnnotationDescriptor<?> descriptor) {
Map<String, Object> result = newHashMap();
int processedValuesFromDescriptor = 0;
final Method[] declaredMethods = run( GetDeclaredMethods.action( annotationType ) );
for ( Method m : declaredMethods ) {
if ( descriptor.containsElement( m.getName() ) ) {
result.put( m.getName(), descriptor.valueOf( m.getName() ) );
processedValuesFromDescriptor++;
}
else if ( m.getDefaultValue() != null ) {
result.put( m.getName(), m.getDefaultValue() );
}
else {
throw log.getNoValueProvidedForAnnotationParameterException(
m.getName(),
annotationType
);
}
}
if ( processedValuesFromDescriptor != descriptor.numberOfElements() ) {
Set<String> unknownParameters = descriptor.getElements().keySet();
unknownParameters.removeAll( result.keySet() );
throw log.getTryingToInstantiateAnnotationWithUnknownParametersException(
annotationType,
unknownParameters
);
}
return result;
}
private int calculateHashCode() {
int hashCode = 0;
for ( Entry<String, Object> member : values.entrySet() ) {
Object value = member.getValue();
int nameHashCode = member.getKey().hashCode();
int valueHashCode =
!value.getClass().isArray() ? value.hashCode() :
value.getClass() == boolean[].class ? Arrays.hashCode( (boolean[]) value ) :
value.getClass() == byte[].class ? Arrays.hashCode( (byte[]) value ) :
value.getClass() == char[].class ? Arrays.hashCode( (char[]) value ) :
value.getClass() == double[].class ? Arrays.hashCode( (double[]) value ) :
value.getClass() == float[].class ? Arrays.hashCode( (float[]) value ) :
value.getClass() == int[].class ? Arrays.hashCode( (int[]) value ) :
value.getClass() == long[].class ? Arrays.hashCode(
(long[]) value
) :
value.getClass() == short[].class ? Arrays
.hashCode( (short[]) value ) :
Arrays.hashCode( (Object[]) value );
hashCode += 127 * nameHashCode ^ valueHashCode;
}
return hashCode;
}
private SortedSet<String> getRegisteredMethodsInAlphabeticalOrder() {
SortedSet<String> result = new TreeSet<String>();
result.addAll( values.keySet() );
return result;
}
private boolean areEqual(Object o1, Object o2) {
return
!o1.getClass().isArray() ? o1.equals( o2 ) :
o1.getClass() == boolean[].class ? Arrays.equals( (boolean[]) o1, (boolean[]) o2 ) :
o1.getClass() == byte[].class ? Arrays.equals( (byte[]) o1, (byte[]) o2 ) :
o1.getClass() == char[].class ? Arrays.equals( (char[]) o1, (char[]) o2 ) :
o1.getClass() == double[].class ? Arrays.equals(
(double[]) o1,
(double[]) o2
) :
o1.getClass() == float[].class ? Arrays.equals(
(float[]) o1,
(float[]) o2
) :
o1.getClass() == int[].class ? Arrays.equals(
(int[]) o1,
(int[]) o2
) :
o1.getClass() == long[].class ? Arrays.equals(
(long[]) o1,
(long[]) o2
) :
o1.getClass() == short[].class ? Arrays.equals(
(short[]) o1,
(short[]) o2
) :
Arrays.equals(
(Object[]) o1,
(Object[]) o2
);
}
private Object getAnnotationMemberValue(Annotation annotation, String name) {
try {
return run( GetDeclaredMethod.action( annotation.annotationType(), name ) ).invoke( annotation );
}
catch (IllegalAccessException e) {
throw log.getUnableToRetrieveAnnotationParameterValueException( e );
}
catch (IllegalArgumentException e) {
throw log.getUnableToRetrieveAnnotationParameterValueException( e );
}
catch (InvocationTargetException e) {
throw log.getUnableToRetrieveAnnotationParameterValueException( e );
}
}
/**
* Runs the given privileged action, using a privileged block if required.
* <p>
* <b>NOTE:</b> This must never be changed into a publicly available method to avoid execution of arbitrary
* privileged actions within HV's protection domain.
*/
private <T> T run(PrivilegedAction<T> action) {
return System.getSecurityManager() != null ? AccessController.doPrivileged( action ) : action.run();
}
}