org.hibernate.bytecode.buildtime
Class AbstractInstrumenter

java.lang.Object
  org.hibernate.bytecode.buildtime.AbstractInstrumenter

All Implemented Interfaces:

Instrumenter

Direct Known Subclasses:

CGLIBInstrumenter, JavassistInstrumenter

public abstract class AbstractInstrumenter
extends Object
implements Instrumenter

Provides the basic templating of how instrumentation should occur.

Author:

Steve Ebersole

Nested Class Summary

protected class

AbstractInstrumenter.CustomFieldFilter Allows control over what exacctly to transform.

Nested classes/interfaces inherited from interface org.hibernate.bytecode.buildtime.Instrumenter

Instrumenter.Options

Field Summary

protected Logger	logger
protected Instrumenter.Options	options

Constructor Summary

AbstractInstrumenter(Logger logger, Instrumenter.Options options)
Creates the basic instrumentation strategy.

Method Summary

protected boolean	checkMagic(File file, long magic)
void	execute(Set files) The main instrumentation entry point.
protected abstract ClassDescriptor	getClassDescriptor(byte[] byecode) Given the bytecode of a java class, retrieve the descriptor for that class.
protected abstract ClassTransformer	getClassTransformer(ClassDescriptor descriptor, Set classNames) Create class transformer for the class.
protected boolean	isClassFile(File file) Does this file represent a compiled class?
protected boolean	isJarFile(File file) Does this file represent a zip file of some format?
protected void	processClassFile(File file, Set classNames) Process a class file.
protected void	processFile(File file, Set classNames) Actually process the file by applying instrumentation transformations to any classes it contains.
protected void	processJarFile(File file, Set classNames) Process an archive file.

Methods inherited from class java.lang.Object

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

Field Detail

logger

protected final Logger logger

options

protected final Instrumenter.Options options

Constructor Detail

AbstractInstrumenter

public AbstractInstrumenter(Logger logger,
                            Instrumenter.Options options)

Creates the basic instrumentation strategy.

Parameters:

logger - The bridge to the environment's logging system.

options - User-supplied options.

Method Detail

getClassDescriptor

protected abstract ClassDescriptor getClassDescriptor(byte[] byecode)
                                               throws Exception

Given the bytecode of a java class, retrieve the descriptor for that class.

Parameters:

byecode - The class bytecode.

Returns:

The class's descriptor

Throws:

Exception - Indicates problems access the bytecode.

getClassTransformer

protected abstract ClassTransformer getClassTransformer(ClassDescriptor descriptor,
                                                        Set classNames)

Create class transformer for the class.

Parameters:

descriptor - The descriptor of the class to be instrumented.

classNames - The names of all classes to be instrumented; the "pipeline" if you will.

Returns:

The transformer for the given class; may return null to indicate that transformation should be skipped (ala already instrumented).

execute

public void execute(Set files)

The main instrumentation entry point. Given a set of files, perform instrumentation on each discovered class file.

Specified by:

execute in interface Instrumenter

Parameters:

files - The files.

isClassFile

protected final boolean isClassFile(File file)
                             throws IOException

Does this file represent a compiled class?

Parameters:

file - The file to check.

Returns:

True if the file is a class; false otherwise.

Throws:

IOException - Indicates problem access the file.

isJarFile

protected final boolean isJarFile(File file)
                           throws IOException

Does this file represent a zip file of some format?

Parameters:

file - The file to check.

Returns:

True if the file is n archive; false otherwise.

Throws:

IOException - Indicates problem access the file.

checkMagic

protected final boolean checkMagic(File file,
                                   long magic)
                            throws IOException

Throws:

IOException

processFile

protected void processFile(File file,
                           Set classNames)
                    throws Exception

Actually process the file by applying instrumentation transformations to any classes it contains.

Again, just like with collectClassNames(java.io.File, java.util.Set) this method can handle both class and archive files.

Parameters:

file - The file to process.

classNames - The 'pipeline' of classes to be processed. Only actually populated when the user specifies to perform extended instrumentation.

Throws:

Exception - Indicates an issue either access files or applying the transformations.

processClassFile

protected void processClassFile(File file,
                                Set classNames)
                         throws Exception

Process a class file. Delegated to from processFile(java.io.File, java.util.Set) in the case of a class file.

Parameters:

file - The class file to process.

classNames - The 'pipeline' of classes to be processed. Only actually populated when the user specifies to perform extended instrumentation.

Throws:

Exception - Indicates an issue either access files or applying the transformations.

processJarFile

protected void processJarFile(File file,
                              Set classNames)
                       throws Exception

Process an archive file. Delegated to from processFile(java.io.File, java.util.Set) in the case of an archive file.

Parameters:

file - The archive file to process.

classNames - The 'pipeline' of classes to be processed. Only actually populated when the user specifies to perform extended instrumentation.

Throws:

Exception - Indicates an issue either access files or applying the transformations.