org.apache.bcel.classfile

Class Constant

java.lang.Object

org.apache.bcel.classfile.Constant

All Implemented Interfaces:

java.lang.Cloneable, Node

Direct Known Subclasses:

ConstantClass, ConstantCP, ConstantDouble, ConstantFloat, ConstantInteger, ConstantLong, ConstantMethodHandle, ConstantMethodType, ConstantModule, ConstantNameAndType, ConstantPackage, ConstantString, ConstantUtf8

public abstract class Constant
extends java.lang.Object
implements java.lang.Cloneable, Node

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.

Method Summary

Modifier and Type	Method and Description
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.
java.lang.Object	clone()
Constant	copy()
abstract void	dump(java.io.DataOutputStream file)
boolean	equals(java.lang.Object obj) Returns value as defined by given BCELComparator strategy.
static BCELComparator	getComparator()
byte	getTag()
int	hashCode() Returns value as defined by given BCELComparator strategy.
static Constant	readConstant(java.io.DataInput dataInput) Reads one constant from the given input, the type depends on a tag byte.
static void	setComparator(BCELComparator comparator)
java.lang.String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

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(java.io.DataOutputStream file)
                   throws java.io.IOException

Throws:

java.io.IOException

getTag

public final byte getTag()

Returns:

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

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

String representation.

copy

public Constant copy()

Returns:

deep copy of this constant

clone

public java.lang.Object clone()

Overrides:

clone in class java.lang.Object

readConstant

public static Constant readConstant(java.io.DataInput dataInput)
                             throws java.io.IOException,
                                    ClassFormatException

Reads one constant from the given input, the type depends on a tag byte.

Parameters:

dataInput - Input stream

Returns:

Constant object

Throws:

java.io.IOException - if an I/O error occurs reading from the given dataInput.

ClassFormatException - if the next byte is not recognized

Since:

6.0 made public

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(java.lang.Object obj)

Returns 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 java.lang.Object

See Also:

Object.equals(java.lang.Object)

hashCode

public int hashCode()

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

Overrides:

hashCode in class java.lang.Object

See Also:

Object.hashCode()