/*
* 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.jdbc.support;
import java.sql.SQLException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.UncategorizedSQLException;
import org.springframework.util.Assert;
/**
* Base class for {@link SQLExceptionTranslator} implementations that allow for
* fallback to some other {@link SQLExceptionTranslator}.
*
* @author Juergen Hoeller
* @since 2.5.6
*/
public abstract class AbstractFallbackSQLExceptionTranslator implements SQLExceptionTranslator {
/** Logger available to subclasses */
protected final Log logger = LogFactory.getLog(getClass());
private SQLExceptionTranslator fallbackTranslator;
/**
* Override the default SQL state fallback translator
* (typically a {@link SQLStateSQLExceptionTranslator}).
*/
public void setFallbackTranslator(SQLExceptionTranslator fallback) {
this.fallbackTranslator = fallback;
}
/**
* Return the fallback exception translator, if any.
*/
public SQLExceptionTranslator getFallbackTranslator() {
return this.fallbackTranslator;
}
/**
* Pre-checks the arguments, calls {@link #doTranslate}, and invokes the
* {@link #getFallbackTranslator() fallback translator} if necessary.
*/
public DataAccessException translate(String task, String sql, SQLException ex) {
Assert.notNull(ex, "Cannot translate a null SQLException");
if (task == null) {
task = "";
}
if (sql == null) {
sql = "";
}
DataAccessException dex = doTranslate(task, sql, ex);
if (dex != null) {
// Specific exception match found.
return dex;
}
// Looking for a fallback...
SQLExceptionTranslator fallback = getFallbackTranslator();
if (fallback != null) {
return fallback.translate(task, sql, ex);
}
// We couldn't identify it more precisely.
return new UncategorizedSQLException(task, sql, ex);
}
/**
* Template method for actually translating the given exception.
* <p>The passed-in arguments will have been pre-checked. Furthermore, this method
* is allowed to return <code>null</code> to indicate that no exception match has
* been found and that fallback translation should kick in.
* @param task readable text describing the task being attempted
* @param sql SQL query or update that caused the problem (may be <code>null</code>)
* @param ex the offending <code>SQLException</code>
* @return the DataAccessException, wrapping the <code>SQLException</code>;
* or <code>null</code> if no exception match found
*/
protected abstract DataAccessException doTranslate(String task, String sql, SQLException ex);
/**
* Build a message <code>String</code> for the given {@link java.sql.SQLException}.
* <p>To be called by translator subclasses when creating an instance of a generic
* {@link org.springframework.dao.DataAccessException} class.
* @param task readable text describing the task being attempted
* @param sql the SQL statement that caused the problem (may be <code>null</code>)
* @param ex the offending <code>SQLException</code>
* @return the message <code>String</code> to use
*/
protected String buildMessage(String task, String sql, SQLException ex) {
return task + "; SQL [" + sql + "]; " + ex.getMessage();
}
}
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