Java tutorial
/** * Copyright 2010-2016 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 * * 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.mybatis.spring; import java.sql.SQLException; import javax.sql.DataSource; import org.apache.ibatis.exceptions.PersistenceException; import org.springframework.dao.DataAccessException; import org.springframework.dao.support.PersistenceExceptionTranslator; import org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator; import org.springframework.jdbc.support.SQLExceptionTranslator; import org.springframework.transaction.TransactionException; /** * Default exception translator. * * Translates MyBatis SqlSession returned exception into a Spring * {@code DataAccessException} using Spring's {@code SQLExceptionTranslator} * Can load {@code SQLExceptionTranslator} eagerly of when the * first exception is translated. * * @author Eduardo Macarron */ public class MyBatisExceptionTranslator implements PersistenceExceptionTranslator { private final DataSource dataSource; private SQLExceptionTranslator exceptionTranslator; /** * Creates a new {@code DataAccessExceptionTranslator} instance. * * @param dataSource DataSource to use to find metadata and establish which error codes are usable. * @param exceptionTranslatorLazyInit if true, the translator instantiates internal stuff only the first time will * have the need to translate exceptions. */ public MyBatisExceptionTranslator(DataSource dataSource, boolean exceptionTranslatorLazyInit) { this.dataSource = dataSource; if (!exceptionTranslatorLazyInit) { this.initExceptionTranslator(); } } /** * {@inheritDoc} */ @Override public DataAccessException translateExceptionIfPossible(RuntimeException e) { if (e instanceof PersistenceException) { // Batch exceptions come inside another PersistenceException // recursion has a risk of infinite loop so better make another if if (e.getCause() instanceof PersistenceException) { e = (PersistenceException) e.getCause(); } if (e.getCause() instanceof SQLException) { this.initExceptionTranslator(); return this.exceptionTranslator.translate(e.getMessage() + "\n", null, (SQLException) e.getCause()); } else if (e.getCause() instanceof TransactionException) { throw (TransactionException) e.getCause(); } return new MyBatisSystemException(e); } return null; } /** * Initializes the internal translator reference. */ private synchronized void initExceptionTranslator() { if (this.exceptionTranslator == null) { this.exceptionTranslator = new SQLErrorCodeSQLExceptionTranslator(this.dataSource); } } }