/*
* Copyright 2002-2008 the original author or authors.
*
* 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.springframework.dao.support;
import java.util.ArrayList;
import java.util.List;
import org.springframework.dao.DataAccessException;
import org.springframework.util.Assert;
/**
* Implementation of {@link PersistenceExceptionTranslator} that supports chaining,
* allowing the addition of PersistenceExceptionTranslator instances in order.
* Returns <code>non-null</code> on the first (if any) match.
*
* @author Rod Johnson
* @author Juergen Hoeller
* @since 2.0
*/
public class ChainedPersistenceExceptionTranslator implements PersistenceExceptionTranslator {
/** List of PersistenceExceptionTranslators */
private final List<PersistenceExceptionTranslator> delegates = new ArrayList<PersistenceExceptionTranslator>(4);
/**
* Add a PersistenceExceptionTranslator to the chained delegate list.
*/
public final void addDelegate(PersistenceExceptionTranslator pet) {
Assert.notNull(pet, "PersistenceExceptionTranslator must not be null");
this.delegates.add(pet);
}
/**
* Return all registered PersistenceExceptionTranslator delegates (as array).
*/
public final PersistenceExceptionTranslator[] getDelegates() {
return this.delegates.toArray(new PersistenceExceptionTranslator[this.delegates.size()]);
}
public DataAccessException translateExceptionIfPossible(RuntimeException ex) {
for (PersistenceExceptionTranslator pet : this.delegates) {
DataAccessException translatedDex = pet.translateExceptionIfPossible(ex);
if (translatedDex != null) {
return translatedDex;
}
}
return null;
}
}
|