Spring Framework

org.springframework.instrument.classloading
Class InstrumentationLoadTimeWeaver

java.lang.Object
  extended by org.springframework.instrument.classloading.InstrumentationLoadTimeWeaver
All Implemented Interfaces:
LoadTimeWeaver

public class InstrumentationLoadTimeWeaver
extends java.lang.Object
implements LoadTimeWeaver

LoadTimeWeaver relying on VM Instrumentation.

Start the JVM specifying the Java agent to be used, like as follows:

-javaagent:path/to/org.springframework.instrument.jar

where org.springframework.instrument.jar is a JAR file containing the InstrumentationSavingAgent class, as shipped with Spring.

In Eclipse, for example, set the "Run configuration"'s JVM args to be of the form:

-javaagent:${project_loc}/lib/org.springframework.instrument.jar

Since:
2.0
Author:
Rod Johnson, Juergen Hoeller
See Also:
InstrumentationSavingAgent

Constructor Summary
InstrumentationLoadTimeWeaver()
          Create a new InstrumentationLoadTimeWeaver for the default ClassLoader.
InstrumentationLoadTimeWeaver(java.lang.ClassLoader classLoader)
          Create a new InstrumentationLoadTimeWeaver for the given ClassLoader.
 
Method Summary
 void addTransformer(java.lang.instrument.ClassFileTransformer transformer)
          Add a ClassFileTransformer to be applied by this LoadTimeWeaver.
 java.lang.ClassLoader getInstrumentableClassLoader()
          We have the ability to weave the current class loader when starting the JVM in this way, so the instrumentable class loader will always be the current loader.
 java.lang.ClassLoader getThrowawayClassLoader()
          This implementation always returns a SimpleThrowawayClassLoader.
static boolean isInstrumentationAvailable()
          Check whether an Instrumentation instance is available for the current VM.
 void removeTransformers()
          Remove all registered transformers, in inverse order of registration.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

InstrumentationLoadTimeWeaver

public InstrumentationLoadTimeWeaver()
Create a new InstrumentationLoadTimeWeaver for the default ClassLoader.


InstrumentationLoadTimeWeaver

public InstrumentationLoadTimeWeaver(java.lang.ClassLoader classLoader)
Create a new InstrumentationLoadTimeWeaver for the given ClassLoader.

Parameters:
classLoader - the ClassLoader that registered transformers are supposed to apply to
Method Detail

addTransformer

public void addTransformer(java.lang.instrument.ClassFileTransformer transformer)
Description copied from interface: LoadTimeWeaver
Add a ClassFileTransformer to be applied by this LoadTimeWeaver.

Specified by:
addTransformer in interface LoadTimeWeaver
Parameters:
transformer - the ClassFileTransformer to add

getInstrumentableClassLoader

public java.lang.ClassLoader getInstrumentableClassLoader()
We have the ability to weave the current class loader when starting the JVM in this way, so the instrumentable class loader will always be the current loader.

Specified by:
getInstrumentableClassLoader in interface LoadTimeWeaver
Returns:
the ClassLoader which will expose instrumented classes according to the registered transformers

getThrowawayClassLoader

public java.lang.ClassLoader getThrowawayClassLoader()
This implementation always returns a SimpleThrowawayClassLoader.

Specified by:
getThrowawayClassLoader in interface LoadTimeWeaver
Returns:
a temporary throwaway ClassLoader; should return a new instance for each call, with no existing state

removeTransformers

public void removeTransformers()
Remove all registered transformers, in inverse order of registration.


isInstrumentationAvailable

public static boolean isInstrumentationAvailable()
Check whether an Instrumentation instance is available for the current VM.

See Also:
getInstrumentation()

Spring Framework