org.apache.derby.impl.sql.execute.xplain
Class XPLAINFactory

java.lang.Object
  extended by org.apache.derby.impl.sql.execute.xplain.XPLAINFactory
All Implemented Interfaces:
XPLAINFactoryIF

public class XPLAINFactory
extends java.lang.Object
implements XPLAINFactoryIF

This is the module implementation of the XPLAINFactoryIF. It gets lazy-loaded when needed. The factory method determines which visitor to use. The visitor is cached in this factory for later reuse.


Field Summary
private  java.lang.String currentSchema
          the current cached schema
private  XPLAINVisitor currentVisitor
          the last instance of a visitor is cached
 
Fields inherited from interface org.apache.derby.iapi.sql.execute.xplain.XPLAINFactoryIF
MODULE
 
Constructor Summary
XPLAINFactory()
           
 
Method Summary
 void freeResources()
          uncache the visitor and reset the factory state
 XPLAINVisitor getXPLAINVisitor()
          the factory method, which gets called to determine and return an appropriate XPLAINVisitor instance
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

currentVisitor

private XPLAINVisitor currentVisitor
the last instance of a visitor is cached


currentSchema

private java.lang.String currentSchema
the current cached schema

Constructor Detail

XPLAINFactory

public XPLAINFactory()
Method Detail

getXPLAINVisitor

public XPLAINVisitor getXPLAINVisitor()
                               throws StandardException
the factory method, which gets called to determine and return an appropriate XPLAINVisitor instance

Specified by:
getXPLAINVisitor in interface XPLAINFactoryIF
Returns:
a XPLAINVisitor to traverse the ResultSetStatistics
Throws:
StandardException
See Also:
XPLAINVisitor

freeResources

public void freeResources()
uncache the visitor and reset the factory state

Specified by:
freeResources in interface XPLAINFactoryIF

Built on Thu 2010-12-23 20:49:13+0000, from revision ???

Apache Derby V10.6 Internals - Copyright © 2004,2007 The Apache Software Foundation. All Rights Reserved.