org.xmlBlaster.contrib.db
Interface I_DbPool

All Superinterfaces:

I_ContribPlugin

All Known Implementing Classes:

DbPool

public interface I_DbPool

extends I_ContribPlugin

Interface to a JDBC pool implementation.

Author:

Marcel Ruff

Method Summary

void	erase(java.sql.Connection con) Destroy the JDBC connection
java.lang.String	getUser()
void	init(I_Info info) Needs to be called after construction.
void	release(java.sql.Connection con) Return the JDBC connection to the pool.
java.sql.Connection	reserve() Access a JDBC connection.
java.sql.Connection	select(java.sql.Connection connection, java.lang.String command, boolean autoCommit, I_ResultCb cb) To have full control.
java.sql.Connection	select(java.sql.Connection connection, java.lang.String command, I_ResultCb cb) Convenience method to execute a SELECT SQL command.
void	select(java.lang.String command, I_ResultCb cb) Convenience method to execute a SELECT SQL command in auto commit mode.
void	shutdown() Close all open connections and destroy the pool.
int	update(java.sql.Connection conn, java.lang.String command)
int	update(java.lang.String command) Convenience method to execute a INSERT/UPDATE/CREATE or DROP SQL command in auto commit mode.

Methods inherited from interface org.xmlBlaster.contrib.I_ContribPlugin

getUsedPropertyKeys

Method Detail

init

public void init(I_Info info)

Needs to be called after construction.

Specified by:

init in interface I_ContribPlugin

Parameters:

info - The configuration

reserve

public java.sql.Connection reserve()
                            throws java.lang.Exception

Access a JDBC connection.

Returns:

The JDBC connection

Throws:

java.lang.Exception

release

public void release(java.sql.Connection con)
             throws java.lang.Exception

Return the JDBC connection to the pool.

Parameters:

con - The JDBC connection

Throws:

java.lang.Exception

getUser

public java.lang.String getUser()

Returns:

the name of the user

erase

public void erase(java.sql.Connection con)
           throws java.lang.Exception

Destroy the JDBC connection

Parameters:

con - The JDBC connection

Throws:

java.lang.Exception

update

public int update(java.lang.String command)
           throws java.lang.Exception

Convenience method to execute a INSERT/UPDATE/CREATE or DROP SQL command in auto commit mode.

Parameters:

command - for example INSERT INTO TEST_POLL VALUES ('1', 'EDDI')

Returns:

Number of touched entries

Throws:

java.lang.Exception - Typically a SQLException

update

public int update(java.sql.Connection conn,
                  java.lang.String command)
           throws java.lang.Exception

Throws:

java.lang.Exception

select

public void select(java.lang.String command,
                   I_ResultCb cb)
            throws java.lang.Exception

Convenience method to execute a SELECT SQL command in auto commit mode.

Parameters:

command - for example SELECT * FROM TEST_POLL

cb - The callback handle for the retrieved ResultSet

Throws:

java.lang.Exception - Typically a SQLException

select

public java.sql.Connection select(java.sql.Connection connection,
                                  java.lang.String command,
                                  I_ResultCb cb)
                           throws java.lang.Exception

Convenience method to execute a SELECT SQL command.

On first call pass connection with null and a valid connection with an open transaction is returned by this method. You can now call this method passing the connection multiple times in the same transaction. When you are done you need to close the connection and put it back into the pool.

Example:

      Connection conn = null;

      try {
         conn = this.dbPool.select(conn, "SELECT A FROM B", new I_ResultCb() {
            public void result(ResultSet rs) throws Exception {
               // Processing result set
            }
         });

         conn = this.dbPool.select(conn, "SELECT B FROM  C", new I_ResultCb() {
            public void result(ResultSet rs) throws Exception {
               // Processing result set
            }
         });
      }
      finally {
         if (conn != null) {
            conn.commit();
            this.dbPool.release(conn);
         }
      }
 

Parameters:

connection - If null a connection is created

command - for example SELECT * FROM TEST_POLL

cb - The callback handle for the retrieved ResultSet

Returns:

If not null you need to put the connection back to the pool yourself

Throws:

java.lang.Exception - Typically a SQLException

select

public java.sql.Connection select(java.sql.Connection connection,
                                  java.lang.String command,
                                  boolean autoCommit,
                                  I_ResultCb cb)
                           throws java.lang.Exception

To have full control.

Parameters:

connection - If null a connection is created

command - for example SELECT * FROM TEST_POLL

autoCommit - if true force auto commit and cleanup the connection, in this case we return null

cb - The callback handle for the retrieved ResultSet

Returns:

If not null you need to put the connection back to the pool yourself

Throws:

java.lang.Exception - Typically a SQLException

shutdown

public void shutdown()
              throws java.lang.Exception

Close all open connections and destroy the pool. All resources are released.

Specified by:

shutdown in interface I_ContribPlugin

Throws:

java.lang.Exception

See Also:

I_Plugin