org.apache.derby.impl.sql.compile

Class OptimizerTracer

java.lang.Object

org.apache.derby.impl.sql.compile.OptimizerTracer

All Implemented Interfaces:

OptionalTool

public class OptimizerTracer
extends java.lang.Object
implements OptionalTool

OptionalTool for tracing the Optimizer.

Constructor Summary

Constructors

Constructor and Description
OptimizerTracer() 0-arg constructor required by the OptionalTool contract

Method Summary

Modifier and Type	Method and Description
void	loadTool(java.lang.String... configurationParameters) Turns on optimizer tracing.
void	unloadTool(java.lang.String... configurationParameters) Print the optimizer trace and turn off tracing.

Methods inherited from class java.lang.Object

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

Constructor Detail

OptimizerTracer

public OptimizerTracer()

0-arg constructor required by the OptionalTool contract

Method Detail

loadTool

public void loadTool(java.lang.String... configurationParameters)
              throws java.sql.SQLException

Turns on optimizer tracing. May take optional parameters:

• xml - If the first arg is the "xml" literal, then trace output will be formatted as xml.
• custom, $class - If the first arg is the "custom" literal, then the next arg must be the name of a class which implements org.apache.derby.iapi.sql.compile.OptTrace and which has a 0-arg constructor. The 0-arg constructor is called and the resulting OptTrace object is plugged in to trace the optimizer.

Specified by:

loadTool in interface OptionalTool

Throws:

java.sql.SQLException

unloadTool

public void unloadTool(java.lang.String... configurationParameters)
                throws java.sql.SQLException

Print the optimizer trace and turn off tracing. Takes optional parameters:

• fileName - Where to write the optimizer trace. If omitted, the trace is written to System.out.

Specified by:

unloadTool in interface OptionalTool

Throws:

java.sql.SQLException