Class Unknown

java.lang.Object

org.apache.bcel.classfile.Attribute

org.apache.bcel.classfile.Unknown

All Implemented Interfaces:

Cloneable, Node

public final class Unknown
extends Attribute

This class represents a reference to an unknown (that is, application-specific) attribute of a class. It is instantiated from the Attribute.readAttribute(java.io.DataInput, ConstantPool) method. Applications that need to read in application-specific attributes should create an UnknownAttributeReader implementation and attach it via Attribute.addAttributeReader(String, UnknownAttributeReader).

See Also:

• Attribute
• UnknownAttributeReader

Field Summary

Fields inherited from class Attribute

constant_pool, EMPTY_ARRAY, length, name_index, tag

Modifier and Type	Field	Description
protected ConstantPool	constant_pool	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter.
static final Attribute[]	EMPTY_ARRAY	Empty array.
protected int	length	Deprecated. (since 6.0) (since 6.0) will be made private; do not access directly, use getter/setter.
protected int	name_index	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter.
protected byte	tag	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter.

Constructor Summary

Constructors

Constructor	Description
Unknown(int nameIndex, int length, byte[] bytes, ConstantPool constantPool)	Constructs a new instance for a non-standard attribute.
Unknown(Unknown unknown)	Constructs a new instance from another instance.

Method Summary

Modifier and Type	Method	Description
void	accept(Visitor v)	Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class.
Attribute	copy(ConstantPool constantPool)	Creates a deep copy of this attribute.
void	dump(DataOutputStream file)	Dumps unknown bytes to file stream.
byte[]	getBytes()	Gets the data bytes.
String	getName()	Gets the name of the attribute.
void	setBytes(byte[] bytes)	Sets the data bytes.
String	toString()

Methods inherited from class Attribute

addAttributeReader, addAttributeReader, clone, getConstantPool, getLength, getNameIndex, getTag, println, readAttribute, readAttribute, readAttribute, removeAttributeReader, setConstantPool, setLength, setNameIndex

Modifier and Type	Method	Description
static void	addAttributeReader(String name, AttributeReader attributeReader)	Deprecated. (6.0) Use Attribute.addAttributeReader(String, UnknownAttributeReader) instead.
static void	addAttributeReader(String name, UnknownAttributeReader unknownAttributeReader)	Add an Attribute reader capable of parsing (user-defined) attributes named "name".
Object	clone()	Use copy() if you want to have a deep copy(), that is, with all references copied correctly.
final ConstantPool	getConstantPool()	Gets the constant pool used by this object.
final int	getLength()	Gets the length of attribute field in bytes.
final int	getNameIndex()	Gets the name index in constant pool of attribute name.
final byte	getTag()	Gets the tag of attribute, that is, its type.
protected static void	println(String msg)	Prints a message to stderr if debug mode is enabled.
static Attribute	readAttribute(DataInput dataInput, ConstantPool constantPool)	Reads one attribute using standard eight-byte Code headers.
static Attribute	readAttribute(DataInput dataInput, ConstantPool constantPool, boolean compactCodeHeader)	Reads one attribute using the selected Code header layout.
static Attribute	readAttribute(DataInputStream dataInputStream, ConstantPool constantPool)	Reads one attribute using standard eight-byte Code headers.
static void	removeAttributeReader(String name)	Remove attribute reader
final void	setConstantPool(ConstantPool constantPool)	Sets the constant pool to be used for this object.
final void	setLength(int length)	Sets the length in bytes.
final void	setNameIndex(int nameIndex)	Sets the name index of attribute.

Methods inherited from class Object

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

Constructor Details

Unknown

public Unknown(int nameIndex,
 int length,
 byte[] bytes,
 ConstantPool constantPool)

Constructs a new instance for a non-standard attribute.

Parameters:

nameIndex - Index in constant pool.

length - Content length in bytes.

bytes - Attribute contents.

constantPool - Array of constants.

Unknown

public Unknown(Unknown unknown)

Constructs a new instance from another instance. Note that both objects use the same references (shallow copy). Use clone() for a physical copy.

Parameters:

unknown - Source.

Method Details

accept

public void accept(Visitor v)

Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class. That is, the hierarchy of methods, fields, attributes, and other elements forms a tree of objects.

Specified by:

accept in interface Node

Specified by:

accept in class Attribute

Parameters:

v - Visitor object.

copy

public Attribute copy(ConstantPool constantPool)

Description copied from class: Attribute

Creates a deep copy of this attribute.

Specified by:

copy in class Attribute

Parameters:

constantPool - constant pool to save.

Returns:

deep copy of this attribute.

dump

public void dump(DataOutputStream file)
          throws IOException

Dumps unknown bytes to file stream.

Overrides:

dump in class Attribute

Parameters:

file - Output file stream.

Throws:

IOException - Thrown if an I/O error occurs.

getBytes

public byte[] getBytes()

Gets the data bytes.

Returns:

data bytes.

getName

public String getName()

Gets the name of the attribute.

Overrides:

getName in class Attribute

Returns:

name of attribute.

setBytes

public void setBytes(byte[] bytes)

Sets the data bytes.

Parameters:

bytes - The bytes to set.

toString

public String toString()

Overrides:

toString in class Attribute

Returns:

String representation.