com.videobug.agent.weaver

Class Weaver

java.lang.Object

com.videobug.agent.weaver.Weaver

All Implemented Interfaces:

IErrorLogger

public class Weaver
extends Object
implements IErrorLogger

This class manages bytecode injection process and weaving logs.

Field Summary

Fields

Modifier and Type	Field and Description
static String	CATEGORY_ERROR_CLASSES
static String	CATEGORY_WOVEN_CLASSES
static String	CLASS_ID_FILE
static String	DATA_ID_FILE
static String	ERROR_LOG_FILE
static String	METHOD_ID_FILE
static String	PROPERTY_FILE
static String	SEPARATOR
static char	SEPARATOR_CHAR

Constructor Summary

Constructors

Constructor and Description
Weaver(File outputDir, WeaveConfig config) Set up the object to manage a weaving process.

Method Summary

Modifier and Type	Method and Description
void	close() Close files written by the weaver.
byte[]	finishClassProcess(com.insidious.common.weaver.ClassInfo classInfo, WeaveLog result) Write the weaving result to files.
void	log(String message) Record a message
void	log(Throwable throwable) Record a runtime error.
void	setDumpEnabled(boolean dump) Set the bytecode dump option.
byte[]	weave(String container, String className, byte[] target, ClassLoader loader) Execute bytecode injection for a given class.

Methods inherited from class java.lang.Object

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

Field Detail

PROPERTY_FILE

public static final String PROPERTY_FILE

See Also:

Constant Field Values

SEPARATOR

public static final String SEPARATOR

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Constant Field Values

SEPARATOR_CHAR

public static final char SEPARATOR_CHAR

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Constant Field Values

CLASS_ID_FILE

public static final String CLASS_ID_FILE

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Constant Field Values

METHOD_ID_FILE

public static final String METHOD_ID_FILE

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Constant Field Values

DATA_ID_FILE

public static final String DATA_ID_FILE

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Constant Field Values

ERROR_LOG_FILE

public static final String ERROR_LOG_FILE

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Constant Field Values

CATEGORY_WOVEN_CLASSES

public static final String CATEGORY_WOVEN_CLASSES

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Constant Field Values

CATEGORY_ERROR_CLASSES

public static final String CATEGORY_ERROR_CLASSES

See Also:

Constant Field Values

Constructor Detail

Weaver

public Weaver(File outputDir,
              WeaveConfig config)

Set up the object to manage a weaving process. This constructor creates files to store the information.

Parameters:

outputDir - location to save the weave data

config - weave configuration

Method Detail

log

public void log(String message)

Record a message

Specified by:

log in interface IErrorLogger

Parameters:

message - string to be logged

log

public void log(Throwable throwable)

Record a runtime error.

Specified by:

log in interface IErrorLogger

Parameters:

throwable - object to be logged

close

public void close()

Close files written by the weaver.

Specified by:

close in interface IErrorLogger

setDumpEnabled

public void setDumpEnabled(boolean dump)

Set the bytecode dump option.

Parameters:

dump - If true is set, the weaver writes the woven class files to the output directory.

weave

public byte[] weave(String container,
                    String className,
                    byte[] target,
                    ClassLoader loader)

Execute bytecode injection for a given class.

Parameters:

container - specifies a location (e.g. a Jar file path) where a class is loaded.

className - specifies a class file path.

target - is the content of the class.

loader - is a class loader that loaded the class.

Returns:

a byte array containing the woven class. This method returns null if an error occurred.

finishClassProcess

public byte[] finishClassProcess(com.insidious.common.weaver.ClassInfo classInfo,
                                 WeaveLog result)

Write the weaving result to files. Without calling this method, this object discards data when a weaving failed.

Parameters:

classInfo - records the class information.

result - records the state after weaving.

Returns:

updated byte code with probes added