// $Id: GroupChainGenerator.java 17620 2009-10-04 19:19:28Z hardy.ferentschik $
/*
* JBoss, Home of Professional Open Source
* Copyright 2009, Red Hat, Inc. and/or its affiliates, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.hibernate.validator.engine.groups;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.validation.GroupDefinitionException;
import javax.validation.GroupSequence;
import javax.validation.ValidationException;
/**
* Used to determine the execution order.
*
* @author Hardy Ferentschik
*/
public class GroupChainGenerator {
private final Map<Class<?>, List<Group>> resolvedSequences = new HashMap<Class<?>, List<Group>>();
public GroupChain getGroupChainFor(Collection<Class<?>> groups) {
if ( groups == null || groups.size() == 0 ) {
throw new IllegalArgumentException( "At least one groups has to be specified." );
}
for ( Class<?> clazz : groups ) {
if ( !clazz.isInterface() ) {
throw new ValidationException( "A group has to be an interface. " + clazz.getName() + " is not." );
}
}
GroupChain chain = new GroupChain();
for ( Class<?> clazz : groups ) {
if ( clazz.getAnnotation( GroupSequence.class ) == null ) {
Group group = new Group( clazz );
chain.insertGroup( group );
insertInheritedGroups( clazz, chain );
}
else {
insertSequence( clazz, chain );
}
}
return chain;
}
private void insertInheritedGroups(Class<?> clazz, GroupChain chain) {
for ( Class<?> extendedInterface : clazz.getInterfaces() ) {
Group group = new Group( extendedInterface );
chain.insertGroup( group );
insertInheritedGroups( extendedInterface, chain );
}
}
private void insertSequence(Class<?> clazz, GroupChain chain) {
List<Group> sequence;
if ( resolvedSequences.containsKey( clazz ) ) {
sequence = resolvedSequences.get( clazz );
}
else {
sequence = resolveSequence( clazz, new ArrayList<Class<?>>() );
}
chain.insertSequence( sequence );
}
private List<Group> resolveSequence(Class<?> group, List<Class<?>> processedSequences) {
if ( processedSequences.contains( group ) ) {
throw new GroupDefinitionException( "Cyclic dependency in groups definition" );
}
else {
processedSequences.add( group );
}
List<Group> resolvedGroupSequence = new ArrayList<Group>();
GroupSequence sequenceAnnotation = group.getAnnotation( GroupSequence.class );
Class<?>[] sequenceArray = sequenceAnnotation.value();
for ( Class<?> clazz : sequenceArray ) {
if ( clazz.getAnnotation( GroupSequence.class ) == null ) {
resolvedGroupSequence.add( new Group( clazz, group ) );
}
else {
List<Group> tmpSequence = resolveSequence( clazz, processedSequences );
addTmpSequence( resolvedGroupSequence, tmpSequence );
}
}
resolvedSequences.put( group, resolvedGroupSequence );
return resolvedGroupSequence;
}
private void addTmpSequence(List<Group> resolvedGroupSequence, List<Group> tmpSequence) {
for ( Group tmpGroup : tmpSequence ) {
if ( resolvedGroupSequence.contains( tmpGroup ) && resolvedGroupSequence.indexOf( tmpGroup ) < resolvedGroupSequence.size() - 1 ) {
throw new GroupDefinitionException( "Unable to expand group sequence." );
}
resolvedGroupSequence.add( tmpGroup );
}
}
}