org.apache.bcel.classfile
Class Attribute

java.lang.Object
  org.apache.bcel.classfile.Attribute

All Implemented Interfaces:

Serializable, Cloneable, Node

Direct Known Subclasses:

Code, ConstantValue, Deprecated, ExceptionTable, InnerClasses, LineNumberTable, LocalVariableTable, PMGClass, Signature, SourceFile, StackMap, Synthetic, Unknown

public abstract class Attribute
extends Object
implements Cloneable, Node, Serializable

Abstract super class for Attribute objects. Currently the ConstantValue, SourceFile, Code, Exceptiontable, LineNumberTable, LocalVariableTable, InnerClasses and Synthetic attributes are supported. The Unknown attribute stands for non-standard-attributes.

Version:

$Id: Attribute.java 386056 2006-03-15 11:31:56Z tcurdt $

See Also:

ConstantValue, SourceFile, Code, Unknown, ExceptionTable, LineNumberTable, LocalVariableTable, InnerClasses, Synthetic, Deprecated, Signature, Serialized Form

Field Summary

protected ConstantPool	constant_pool
protected int	length
protected int	name_index
protected byte	tag

Constructor Summary

protected

Attribute(byte tag, int name_index, int length, ConstantPool constant_pool)

Method Summary

abstract void	accept(Visitor v) Called by objects that are traversing the nodes of the tree implicitely defined by the contents of a Java class.
static void	addAttributeReader(String name, AttributeReader r) Add an Attribute reader capable of parsing (user-defined) attributes named "name".
Object	clone() Use copy() if you want to have a deep copy(), i.e., with all references copied correctly.
abstract Attribute	copy(ConstantPool _constant_pool)
void	dump(DataOutputStream file) Dump attribute to file stream in binary format.
ConstantPool	getConstantPool()
int	getLength()
int	getNameIndex()
byte	getTag()
static Attribute	readAttribute(DataInputStream file, ConstantPool constant_pool)
static void	removeAttributeReader(String name) Remove attribute reader
void	setConstantPool(ConstantPool constant_pool)
void	setLength(int length)
void	setNameIndex(int name_index)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

name_index

protected int name_index

length

protected int length

tag

protected byte tag

constant_pool

protected ConstantPool constant_pool

Constructor Detail

Attribute

protected Attribute(byte tag,
                    int name_index,
                    int length,
                    ConstantPool constant_pool)

Method Detail

accept

public abstract void accept(Visitor v)

Called by objects that are traversing the nodes of the tree implicitely defined by the contents of a Java class. I.e., the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.

Specified by:

accept in interface Node

Parameters:

v - Visitor object

dump

public void dump(DataOutputStream file)
          throws IOException

Dump attribute to file stream in binary format.

Parameters:

file - Output file stream

Throws:

IOException

addAttributeReader

public static void addAttributeReader(String name,
                                      AttributeReader r)

Add an Attribute reader capable of parsing (user-defined) attributes named "name". You should not add readers for the standard attributes such as "LineNumberTable", because those are handled internally.

Parameters:

name - the name of the attribute as stored in the class file

r - the reader object

removeAttributeReader

public static void removeAttributeReader(String name)

Remove attribute reader

Parameters:

name - the name of the attribute as stored in the class file

readAttribute

public static final Attribute readAttribute(DataInputStream file,
                                            ConstantPool constant_pool)
                                     throws IOException,
                                            ClassFormatException

Throws:

IOException

ClassFormatException

getLength

public final int getLength()

Returns:

Length of attribute field in bytes.

setLength

public final void setLength(int length)

Parameters:

length - length in bytes.

setNameIndex

public final void setNameIndex(int name_index)

Parameters:

name_index - of attribute.

getNameIndex

public final int getNameIndex()

Returns:

Name index in constant pool of attribute name.

getTag

public final byte getTag()

Returns:

Tag of attribute, i.e., its type. Value may not be altered, thus there is no setTag() method.

getConstantPool

public final ConstantPool getConstantPool()

Returns:

Constant pool used by this object.

See Also:

ConstantPool

setConstantPool

public final void setConstantPool(ConstantPool constant_pool)

Parameters:

constant_pool - Constant pool to be used for this object.

See Also:

ConstantPool

clone

public Object clone()

Use copy() if you want to have a deep copy(), i.e., with all references copied correctly.

Overrides:

clone in class Object

Returns:

shallow copy of this attribute

copy

public abstract Attribute copy(ConstantPool _constant_pool)

Returns:

deep copy of this attribute

toString

public String toString()

Overrides:

toString in class Object

Returns:

attribute name.