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/*
* Distributed as part of c3p0 v.0.9.5.3
*
* Copyright (C) 2018 Machinery For Change, Inc.
*
* Author: Steve Waldman
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of EITHER:
*
* 1) The GNU Lesser General Public License (LGPL), version 2.1, as
* published by the Free Software Foundation
*
* OR
*
* 2) The Eclipse Public License (EPL), version 1.0
*
* You may choose which license to accept if you wish to redistribute
* or modify this work. You may offer derivatives of this work
* under the license you have chosen, or you may provide the same
* choice of license which you have been offered here.
*
* This software 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.
*
* You should have received copies of both LGPL v2.1 and EPL v1.0
* along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
* If not, the text of these licenses are currently available at
*
* LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php
*
*/
package com.mchange.v2.c3p0;
import java.sql.Statement;
import java.sql.SQLException;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;
/**
* Most clients need never use or know about this interface -- c3p0-provided Statements
* can be treated like any other Statement.
*
* An interface implemented by proxy Connections returned
* by c3p0 PooledDataSources. It provides protected access to the underlying
* dbms-vendor specific Connection, which may be useful if you want to
* access non-standard API offered by your jdbc driver.
*/
public interface C3P0ProxyStatement extends Statement
{
/**
* A token representing an unwrapped, unproxied jdbc Connection
* for use in {@link #rawStatementOperation}
*/
public final static Object RAW_STATEMENT = new Object();
/**
*
Allows one to work with the unproxied, raw vendor-provided Statement . Some
* database companies never got over the "common interfaces mean
* no more vendor lock-in!" thing, and offer non-standard API
* on their Statements. This method permits you to "pierce" the
* connection-pooling layer to call non-standard methods on the
* original Statement, or to pass the original Statement to
* functions that are not implementation neutral.
*
* To use this functionality, you'll need to cast a Statement
* retrieved from a c3p0-provided Connection to a
* C3P0ProxyStatement.
*
* This method works by making a reflective call of method m on
* Object target (which may be null for static methods), passing
* and argument list args. For the method target, or for any argument,
* you may substitute the special token C3P0ProxyStatement.RAW_STATEMENT
*
* Any ResultSets returned by the operation will be proxied
* and c3p0-managed, meaning that these resources will be automatically closed
* if the user does not close them first when this Statement is closed or checked
* into the statement cache. Any other resources returned by the operation are the user's
* responsibility to clean up!
*
* If you have turned statement pooling on, incautious use of this method can corrupt the
* PreparedStatement cache, by breaking the invariant
* that all cached PreparedStatements should be equivalent to a PreparedStatement newly created
* with the same arguments to prepareStatement(...) or prepareCall(...). If your vendor supplies API
* that allows you to modify the state or configuration of a Statement in some nonstandard way,
* and you do not undo this modification prior to closing the Statement or the Connection that
* prepared it, future preparers of the same Statement may or may not see your modification,
* depending on your use of the cache. Thus, it is inadvisable to use this method to call
* nonstandard mutators on PreparedStatements if statement pooling is turned on..
*/
public Object rawStatementOperation(Method m, Object target, Object[] args)
throws IllegalAccessException, IllegalArgumentException, InvocationTargetException, SQLException;
}