package org.apache.commons.jcs.auxiliary.disk.jdbc.mysql;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.sql.DataSource;
import org.apache.commons.jcs.auxiliary.disk.jdbc.TableState;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* The MySQL Table Optimizer can optimize MySQL tables. It knows how to optimize for MySQL databases
* in particular and how to repair the table if it is corrupted in the process.
* <p>
* We will probably be able to abstract out a generic optimizer interface from this class in the
* future.
* <p>
* @author Aaron Smuts
*/
public class MySQLTableOptimizer
{
/** The logger */
private static final Log log = LogFactory.getLog( MySQLTableOptimizer.class );
/** The data source */
private DataSource dataSource = null;
/** The name of the table. */
private String tableName = null;
/** optimizing, etc. */
private TableState tableState;
/**
* This constructs an optimizer with the disk cacn properties.
* <p>
* @param attributes
* @param tableState We mark the table status as optimizing when this is happening.
* @param dataSource access to the database
*/
public MySQLTableOptimizer( MySQLDiskCacheAttributes attributes, TableState tableState, DataSource dataSource )
{
setTableName( attributes.getTableName() );
this.tableState = tableState;
this.dataSource = dataSource;
}
/**
* A scheduler will call this method. When it is called the table state is marked as optimizing.
* TODO we need to verify that no deletions are running before we call optimize. We should wait
* if a deletion is in progress.
* <p>
* This restores when there is an optimization error. The error output looks like this:
*
* <pre>
* mysql> optimize table JCS_STORE_FLIGHT_OPTION_ITINERARY;
* +---------------------------------------------+----------+----------+---------------------+
* | Table | Op | Msg_type | Msg_text |
* +---------------------------------------------+----------+----------+---------------------+
* | jcs_cache.JCS_STORE_FLIGHT_OPTION_ITINERARY | optimize | error | 2 when fixing table |
* | jcs_cache.JCS_STORE_FLIGHT_OPTION_ITINERARY | optimize | status | Operation failed |
* +---------------------------------------------+----------+----------+---------------------+
* 2 rows in set (51.78 sec)
* </pre>
*
* A successful repair response looks like this:
*
* <pre>
* mysql> REPAIR TABLE JCS_STORE_FLIGHT_OPTION_ITINERARY;
* +---------------------------------------------+--------+----------+----------------------------------------------+
* | Table | Op | Msg_type | Msg_text |
* +---------------------------------------------+--------+----------+----------------------------------------------+
* | jcs_cache.JCS_STORE_FLIGHT_OPTION_ITINERARY | repair | error | 2 when fixing table |
* | jcs_cache.JCS_STORE_FLIGHT_OPTION_ITINERARY | repair | warning | Number of rows changed from 131276 to 260461 |
* | jcs_cache.JCS_STORE_FLIGHT_OPTION_ITINERARY | repair | status | OK |
* +---------------------------------------------+--------+----------+----------------------------------------------+
* 3 rows in set (3 min 5.94 sec)
* </pre>
*
* A successful optimization looks like this:
*
* <pre>
* mysql> optimize table JCS_STORE_DEFAULT;
* +-----------------------------+----------+----------+----------+
* | Table | Op | Msg_type | Msg_text |
* +-----------------------------+----------+----------+----------+
* | jcs_cache.JCS_STORE_DEFAULT | optimize | status | OK |
* +-----------------------------+----------+----------+----------+
* 1 row in set (1.10 sec)
* </pre>
* @return true if it worked
*/
public boolean optimizeTable()
{
long start = System.currentTimeMillis();
boolean success = false;
if ( tableState.getState() == TableState.OPTIMIZATION_RUNNING )
{
log
.warn( "Skipping optimization. Optimize was called, but the table state indicates that an optimization is currently running." );
return false;
}
try
{
tableState.setState( TableState.OPTIMIZATION_RUNNING );
if ( log.isInfoEnabled() )
{
log.info( "Optimizing table [" + this.getTableName() + "]" );
}
Connection con;
try
{
con = dataSource.getConnection();
}
catch ( SQLException e )
{
log.error( "Problem getting connection.", e );
return false;
}
try
{
// TEST
Statement sStatement = null;
try
{
sStatement = con.createStatement();
ResultSet rs = sStatement.executeQuery( "optimize table " + this.getTableName() );
// first row is error, then status
// if there is only one row in the result set, everything
// should be fine.
// This may be mysql version specific.
if ( rs.next() )
{
String status = rs.getString( "Msg_type" );
String message = rs.getString( "Msg_text" );
if ( log.isInfoEnabled() )
{
log.info( "Message Type: " + status );
log.info( "Message: " + message );
}
if ( "error".equals( status ) )
{
log.warn( "Optimization was in error. Will attempt to repair the table. Message: "
+ message );
// try to repair the table.
success = repairTable( sStatement );
}
else
{
success = true;
}
}
// log the table status
String statusString = getTableStatus( sStatement );
if ( log.isInfoEnabled() )
{
log.info( "Table status after optimizing table [" + this.getTableName() + "]\n" + statusString );
}
}
catch ( SQLException e )
{
log.error( "Problem optimizing table [" + this.getTableName() + "]", e );
return false;
}
finally
{
if (sStatement != null)
{
try
{
sStatement.close();
}
catch ( SQLException e )
{
log.error( "Problem closing statement.", e );
}
}
}
}
finally
{
try
{
con.close();
}
catch ( SQLException e )
{
log.error( "Problem closing connection.", e );
}
}
}
finally
{
tableState.setState( TableState.FREE );
long end = System.currentTimeMillis();
if ( log.isInfoEnabled() )
{
log.info( "Optimization of table [" + this.getTableName() + "] took " + ( end - start ) + " ms." );
}
}
return success;
}
/**
* This calls show table status and returns the result as a String.
* <p>
* @param sStatement
* @return String
* @throws SQLException
*/
protected String getTableStatus( Statement sStatement )
throws SQLException
{
ResultSet statusResultSet = sStatement.executeQuery( "show table status" );
StringBuilder statusString = new StringBuilder();
int numColumns = statusResultSet.getMetaData().getColumnCount();
while ( statusResultSet.next() )
{
statusString.append( "\n" );
for ( int i = 1; i <= numColumns; i++ )
{
statusString.append( statusResultSet.getMetaData().getColumnLabel( i ) + " ["
+ statusResultSet.getString( i ) + "] | " );
}
}
return statusString.toString();
}
/**
* This is called if the optimization is in error.
* <p>
* It looks for "OK" in response. If it find "OK" as a message in any result set row, it returns
* true. Otherwise we assume that the repair failed.
* <p>
* @param sStatement
* @return true if successful
* @throws SQLException
*/
protected boolean repairTable( Statement sStatement )
throws SQLException
{
boolean success = false;
// if( message != null && message.indexOf( ) )
ResultSet repairResult = sStatement.executeQuery( "repair table " + this.getTableName() );
StringBuilder repairString = new StringBuilder();
int numColumns = repairResult.getMetaData().getColumnCount();
while ( repairResult.next() )
{
for ( int i = 1; i <= numColumns; i++ )
{
repairString.append( repairResult.getMetaData().getColumnLabel( i ) + " [" + repairResult.getString( i )
+ "] | " );
}
String message = repairResult.getString( "Msg_text" );
if ( "OK".equals( message ) )
{
success = true;
}
}
if ( log.isInfoEnabled() )
{
log.info( repairString );
}
if ( !success )
{
log.warn( "Failed to repair the table. " + repairString );
}
return success;
}
/**
* @param tableName The tableName to set.
*/
public void setTableName( String tableName )
{
this.tableName = tableName;
}
/**
* @return Returns the tableName.
*/
public String getTableName()
{
return tableName;
}
}