org.apache.bcel.classfile
Class Constant

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

All Implemented Interfaces:

Serializable, Cloneable, Node

Direct Known Subclasses:

ConstantClass, ConstantCP, ConstantDouble, ConstantFloat, ConstantInteger, ConstantLong, ConstantNameAndType, ConstantString, ConstantUtf8

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

Abstract superclass for classes to represent the different constant types in the constant pool of a class file. The classes keep closely to the JVM specification.

Version:

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

Author:

M. Dahm

See Also:

Serialized Form

Field Summary

private static BCELComparator	_cmp
protected byte	tag

Constructor Summary

Constant(byte tag)

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.
Object	clone()
Constant	copy()
abstract void	dump(DataOutputStream file)
boolean	equals(Object obj) Return value as defined by given BCELComparator strategy.
static BCELComparator	getComparator()
byte	getTag()
int	hashCode() Return value as defined by given BCELComparator strategy.
(package private) static Constant	readConstant(DataInputStream file) Read one constant from the given file, the type depends on a tag byte.
static void	setComparator(BCELComparator comparator)
String	toString()

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

_cmp

private static BCELComparator _cmp

tag

protected byte tag

Constructor Detail

Constant

Constant(byte tag)

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 abstract void dump(DataOutputStream file)
                   throws IOException

Throws:

IOException

getTag

public final byte getTag()

Returns:

Tag of constant, i.e., its type. No setTag() method to avoid confusion.

toString

public String toString()

Overrides:

toString in class Object

Returns:

String representation.

copy

public Constant copy()

Returns:

deep copy of this constant

clone

public Object clone()
             throws CloneNotSupportedException

Overrides:

clone in class Object

Throws:

CloneNotSupportedException

readConstant

static final Constant readConstant(DataInputStream file)
                            throws IOException,
                                   ClassFormatException

Read one constant from the given file, the type depends on a tag byte.

Parameters:

file - Input stream

Returns:

Constant object

Throws:

IOException

ClassFormatException

getComparator

public static BCELComparator getComparator()

Returns:

Comparison strategy object

setComparator

public static void setComparator(BCELComparator comparator)

Parameters:

comparator - Comparison strategy object

equals

public boolean equals(Object obj)

Return value as defined by given BCELComparator strategy. By default two Constant objects are said to be equal when the result of toString() is equal.

Overrides:

equals in class Object

See Also:

Object.equals(java.lang.Object)

hashCode

public int hashCode()

Return value as defined by given BCELComparator strategy. By default return the hashcode of the result of toString().

Overrides:

hashCode in class Object

See Also:

Object.hashCode()