net.sf.farrago.query
Class FarragoReentrantStmt

java.lang.Object
  net.sf.farrago.query.FarragoReentrantStmt

Direct Known Subclasses:

DdlRelationalHandler.ReentrantIndexBuilderStmt, FarragoReentrantStmtExecutor

public abstract class FarragoReentrantStmt
extends Object

FarragoReentrantStmt provides infrastructure for safely executing a reentrant statement as part of the preparation of some outer statement. The caller is required to define a subclass which executes the internal statement; the base class takes care of releasing resources correctly regardless of how the internal statement fares.

Version:

$Id: //open/dev/farrago/src/net/sf/farrago/query/FarragoReentrantStmt.java#10 $

Author:

John V. Sichi

Field Summary

private FarragoSessionPreparingStmt	preparingStmt
private FarragoSessionStmtContext	rootStmtContext
private FarragoSessionStmtContext	stmtContext

Constructor Summary

FarragoReentrantStmt(FarragoSessionStmtContext rootStmtContext)

Method Summary

void	execute(FarragoSession session, boolean allocateSession) Executes the reentrant statement; subclass specified what to do in executeImpl().
protected abstract void	executeImpl() Supplies subclass-specific behavior.
protected FarragoSessionPreparingStmt	getPreparingStmt()
protected FarragoSessionStmtContext	getRootStmtContext()
protected FarragoSessionStmtContext	getStmtContext()

Methods inherited from class java.lang.Object

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

Field Detail

preparingStmt

private FarragoSessionPreparingStmt preparingStmt

stmtContext

private FarragoSessionStmtContext stmtContext

rootStmtContext

private FarragoSessionStmtContext rootStmtContext

Constructor Detail

FarragoReentrantStmt

public FarragoReentrantStmt(FarragoSessionStmtContext rootStmtContext)

Method Detail

getPreparingStmt

protected FarragoSessionPreparingStmt getPreparingStmt()

getStmtContext

protected FarragoSessionStmtContext getStmtContext()

getRootStmtContext

protected FarragoSessionStmtContext getRootStmtContext()

executeImpl

protected abstract void executeImpl()
                             throws Exception

Supplies subclass-specific behavior.

Throws:

Exception

execute

public void execute(FarragoSession session,
                    boolean allocateSession)

Executes the reentrant statement; subclass specified what to do in executeImpl().

Parameters:

session - session on which to execute

allocateSession - if true, allocate a re-entrant session; if false, use the given session directly