/*
 * Copyright 2002-2016 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
 *
 *      https://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 org.springframework.dao.DataAccessException;
import org.springframework.lang.Nullable;

Interface implemented by Spring integrations with data access technologies
that throw runtime exceptions, such as JPA and Hibernate.
This allows consistent usage of combined exception translation functionality,
without forcing a single translator to understand every single possible type
of exception.
Author:
Rod Johnson, Juergen Hoeller
Since:
2.0/**
 * Interface implemented by Spring integrations with data access technologies
 * that throw runtime exceptions, such as JPA and Hibernate.
 *
 * <p>This allows consistent usage of combined exception translation functionality,
 * without forcing a single translator to understand every single possible type
 * of exception.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 2.0
 */
@FunctionalInterface
public interface PersistenceExceptionTranslator {

	
Translate the given runtime exception thrown by a persistence framework to a corresponding exception from Spring's generic DataAccessException hierarchy, if possible. 
Do not translate exceptions that are not understood by this translator:
for example, if coming from another persistence framework, or resulting
from user code or otherwise unrelated to persistence.
Of particular importance is the correct translation to
DataIntegrityViolationException, for example on constraint violation.
Implementations may use Spring JDBC's sophisticated exception translation
to provide further information in the event of SQLException as a root cause.
Params:
ex – a RuntimeException to translate
See Also:
DataIntegrityViolationException
SQLExceptionTranslator
Returns:
the corresponding DataAccessException (or null if the exception could not be translated, as in this case it may result from user code rather than from an actual persistence problem)/**
	 * Translate the given runtime exception thrown by a persistence framework to a
	 * corresponding exception from Spring's generic
	 * {@link org.springframework.dao.DataAccessException} hierarchy, if possible.
	 * <p>Do not translate exceptions that are not understood by this translator:
	 * for example, if coming from another persistence framework, or resulting
	 * from user code or otherwise unrelated to persistence.
	 * <p>Of particular importance is the correct translation to
	 * DataIntegrityViolationException, for example on constraint violation.
	 * Implementations may use Spring JDBC's sophisticated exception translation
	 * to provide further information in the event of SQLException as a root cause.
	 * @param ex a RuntimeException to translate
	 * @return the corresponding DataAccessException (or {@code null} if the
	 * exception could not be translated, as in this case it may result from
	 * user code rather than from an actual persistence problem)
	 * @see org.springframework.dao.DataIntegrityViolationException
	 * @see org.springframework.jdbc.support.SQLExceptionTranslator
	 */
	@Nullable
	DataAccessException translateExceptionIfPossible(RuntimeException ex);

}