com.google.monitoring.runtime.instrumentation

Class AllocationInstrumenter

java.lang.Object

com.google.monitoring.runtime.instrumentation.AllocationInstrumenter

All Implemented Interfaces:

ClassFileTransformer

public class AllocationInstrumenter
extends Object
implements ClassFileTransformer

Instruments bytecodes that allocate heap memory to call a recording hook. This will add a static invocation to a recorder function to any bytecode that looks like it will be allocating heap memory allowing users to implement heap profiling schemes.

Author:

Ami Fischman, Jeremy Manson

Method Summary

Modifier and Type	Method and Description
static byte[]	instrument(byte[] originalBytes, ClassLoader loader)
static byte[]	instrument(byte[] originalBytes, String recorderClass, String recorderMethod, ClassLoader loader) Given the bytes representing a class, go through all the bytecode in it and instrument any occurences of new/newarray/anewarray/multianewarray with pre- and post-allocation hooks.
static void	premain(String agentArgs, Instrumentation inst)
byte[]	transform(ClassLoader loader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] origBytes)

Methods inherited from class java.lang.Object

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

Method Detail

premain

public static void premain(String agentArgs,
                           Instrumentation inst)

transform

public byte[] transform(ClassLoader loader,
                        String className,
                        Class<?> classBeingRedefined,
                        ProtectionDomain protectionDomain,
                        byte[] origBytes)

Specified by:

transform in interface ClassFileTransformer

instrument

public static byte[] instrument(byte[] originalBytes,
                                String recorderClass,
                                String recorderMethod,
                                ClassLoader loader)

Given the bytes representing a class, go through all the bytecode in it and instrument any occurences of new/newarray/anewarray/multianewarray with pre- and post-allocation hooks. Even more fun, intercept calls to the reflection API's Array.newInstance() and instrument those too.

Parameters:

originalBytes - the original byte[] code.

recorderClass - the String internal name of the class containing the recorder method to run.

recorderMethod - the String name of the recorder method to run.

loader - the ClassLoader for this class.

Returns:

the instrumented byte[] code.

instrument

public static byte[] instrument(byte[] originalBytes,
                                ClassLoader loader)

Parameters:

originalBytes - The original version of the class.

loader - The ClassLoader of this class.

Returns:

the instrumented version of this class.

See Also:

documentation for the 4-arg version. This is a convenience version that uses the recorder in this class.