org.apache.tomcat.jdbc.pool.interceptor

Class ConnectionState

java.lang.Object

org.apache.tomcat.jdbc.pool.JdbcInterceptor

org.apache.tomcat.jdbc.pool.interceptor.ConnectionState

All Implemented Interfaces:

InvocationHandler

public class ConnectionState
extends JdbcInterceptor

Interceptor that keep track of connection state to avoid roundtrips to the database. The ConnectionPool is optimized to do as little work as possible. The pool itself doesn't remember settings like Connection.setAutoCommit(boolean), Connection.setReadOnly(boolean), Connection.setCatalog(String) or Connection.setTransactionIsolation(int). It relies on the application to remember how and when these settings have been applied. In the cases where the application code doesn't know or want to keep track of the state, this interceptor helps cache the state, and it also avoids roundtrips to the database asking for it.

Field Summary

Fields

Modifier and Type	Field and Description
protected Boolean	autoCommit
protected String	catalog
protected Boolean	readOnly
protected String[]	readState
protected Integer	transactionIsolation
protected String[]	writeState

Fields inherited from class org.apache.tomcat.jdbc.pool.JdbcInterceptor

CLOSE_VAL, EQUALS_VAL, GETCONNECTION_VAL, HASHCODE_VAL, ISCLOSED_VAL, ISVALID_VAL, ISWRAPPERFOR_VAL, properties, TOSTRING_VAL, UNWRAP_VAL

Constructor Summary

Constructors

Constructor and Description
ConnectionState()

Method Summary

Modifier and Type	Method and Description
void	disconnected(ConnectionPool parent, PooledConnection con, boolean finalizing) Called when Connection.close() is called on the underlying connection.
Object	invoke(Object proxy, Method method, Object[] args) Gets invoked each time an operation on Connection is invoked.
void	reset(ConnectionPool parent, PooledConnection con) Gets called each time the connection is borrowed from the pool This means that if an interceptor holds a reference to the connection the interceptor can be reused for another connection.

Methods inherited from class org.apache.tomcat.jdbc.pool.JdbcInterceptor

compare, compare, getNext, getProperties, isUseEquals, poolClosed, poolStarted, setNext, setProperties, setUseEquals

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

readState

protected final String[] readState

writeState

protected final String[] writeState

autoCommit

protected Boolean autoCommit

transactionIsolation

protected Integer transactionIsolation

readOnly

protected Boolean readOnly

catalog

protected String catalog

Constructor Detail

ConnectionState

public ConnectionState()

Method Detail

reset

public void reset(ConnectionPool parent,
                  PooledConnection con)

Description copied from class: JdbcInterceptor

Gets called each time the connection is borrowed from the pool This means that if an interceptor holds a reference to the connection the interceptor can be reused for another connection.
This method may be called with null as both arguments when we are closing down the connection.

Specified by:

reset in class JdbcInterceptor

Parameters:

parent - - the connection pool owning the connection

con - - the pooled connection

disconnected

public void disconnected(ConnectionPool parent,
                         PooledConnection con,
                         boolean finalizing)

Description copied from class: JdbcInterceptor

Called when Connection.close() is called on the underlying connection. This is to notify the interceptors, that the physical connection has been released. Implementation of this method should be thought through with care, as no actions should trigger an exception.

Overrides:

disconnected in class JdbcInterceptor

Parameters:

parent - - the connection pool that this connection belongs to

con - - the pooled connection that holds this connection

finalizing - - if this connection is finalizing. True means that the pooled connection will not reconnect the underlying connection

invoke

public Object invoke(Object proxy,
                     Method method,
                     Object[] args)
              throws Throwable

Description copied from class: JdbcInterceptor

Gets invoked each time an operation on Connection is invoked.

Specified by:

invoke in interface InvocationHandler

Overrides:

invoke in class JdbcInterceptor

Throws:

Throwable