com.xdev.jadoth.sqlengine.interfaces.ConnectionProvider Maven / Gradle / Ivy
package com.xdev.jadoth.sqlengine.interfaces;
/*-
* #%L
* XDEV Application Framework
* %%
* Copyright (C) 2003 - 2020 XDEV Software
* %%
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Lesser Public License for more details.
*
* You should have received a copy of the GNU General Lesser Public
* License along with this program. If not, see
* .
* #L%
*/
import java.sql.Connection;
import java.sql.SQLException;
import com.xdev.jadoth.sqlengine.dbms.DbmsAdaptor;
import com.xdev.jadoth.sqlengine.dbms.DbmsConnectionInformation;
import com.xdev.jadoth.sqlengine.exceptions.SQLEngineException;
/**
* A connection provider manages JDBC connections and returns an appropriate
* connection instance.
* In the trivial case, this can be always the same connection instance.
* Other implementations might apply more sophisticated connection management
* like connection pooling, return connections on a per-thread basis and/or take
* the application context into account for making the decision which connection
* to provide.
*
* For every connection, there is also provided an apropriate DbmsAdaptor
* instance for that.
* This may be always the same DbmsAdaptor instance if all managed connections
* connect to the same DBMS type or, depending on implementation, may as well be
* a different DbmsAdaptor instance depending on the used connection.
*
* @param
* the generic type
* @author Thomas Muenz
*/
public interface ConnectionProvider>
{
/**
* Releases all resources held by this connection provider instance.
*/
public void close();
/**
* Closes a specific connection used by this connection provider instance.
*
* @param connection
* the connection instance to be closed
*/
public void closeConnection(Connection connection);
/**
* Returns a connection instance as this connection provider sees fit.
*
* @return the connection
*/
public Connection getConnection();
/**
* Gets the dbms adaptor.
*
* @return the apropriate DbmsAdaptor instance for all provided connections
*/
public A getDbmsAdaptor();
/**
* Default implementation of ConnectionProvider that
* encapsulates a single JDBC connection instance. Thus, the connection
* instance provided by this connection provider is always the same.
*
* @param
* the generic type
* @author Thomas Muenz
*/
public class Body> implements ConnectionProvider
{
// /////////////////////////////////////////////////////////////////////////
// instance fields //
// //////////////////
/** The dbms connection information. */
private DbmsConnectionInformation dbmsConnectionInformation;
/** The connection. */
private Connection connection;
/** The dbms adaptor. */
private A dbmsAdaptor;
// /////////////////////////////////////////////////////////////////////////
// constructors //
// ///////////////
/**
* Instantiates a new body.
*
* @param conInfo
* the con info
* @param jdbcUrlExtension
* the jdbc url extension
*/
public Body(final DbmsConnectionInformation conInfo)
{
super();
this.dbmsConnectionInformation = conInfo;
this.dbmsAdaptor = conInfo.getDbmsAdaptor();
this.connection = conInfo.createConnection();
}
// /////////////////////////////////////////////////////////////////////////
// getters //
// ///////////////////
/**
* Returns the encapsulated JDBC connection instance.
*
* @return the connection
*/
@Override
public Connection getConnection()
{
return this.connection;
}
/**
* Gets the dbms adaptor.
*
* @return the dbmsAdaptor
*/
@Override
public A getDbmsAdaptor()
{
return this.dbmsAdaptor;
}
/**
* Gets the dbms connection information.
*
* @return the dbmsConnectionInformation that provided the JDBC
* Connection and DbmsAdaptor instances
*/
public DbmsConnectionInformation getDbmsConnectionInformation()
{
return dbmsConnectionInformation;
}
// /////////////////////////////////////////////////////////////////////////
// override methods //
// ///////////////////
/**
* Closes the encapsulated connection.
*/
@Override
public void close()
{
if(this.connection == null)
return;
try
{
this.connection.close();
}
catch(SQLException e)
{
throw new SQLEngineException(e);
}
}
/**
* Calls close() if connection is the encapsulated
* connection. Does nothing otherwise.
*
* @param connection
* the connection
*/
@Override
public void closeConnection(final Connection connection)
{
if(this.connection != connection)
return;
this.close();
}
}
}