javar.constantpool
Class ConstantPool

java.lang.Object
  |
  +--javar.constantpool.ConstantPool

public class ConstantPool

extends Object

This class represents the constant pool of a java class file

Author:

Ben Litchfield

Constructor Summary

ConstantPool()
Default Constructor

ConstantPool(DataInputStream in)
Default Constructor

Method Summary

long	addClass(String className) This will add an entry to the constant pool
long	addMethod(String className, String name, String type) This will add a new method to the pool
long	addNameAndType(String name, String type) This will add a name and type entry to the pool
long	addString(String entry) This will add an entry to the constant pool.
long	addUTF8(String entry) This will add an entry to the constant pool.
long	findUTF8(String string) This will find the index to the string, or -1 if it was not found.
ConstantPoolEntry	getEntry(long index) This will get an entry in the pool for you
long	getSize() This will return the number of entries that are contained
boolean	isReady(long index) This will tell you if the selected entry is ready to be read.
Iterator	listEntriesByType(byte code) This will get all entries in the constant pool based on a specific type.
byte[]	toBytes() This will get the constant pool as a set of bytes that are needed.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstantPool

public ConstantPool()

Default Constructor

ConstantPool

public ConstantPool(DataInputStream in)
             throws JavarParseException

Default Constructor

Method Detail

listEntriesByType

public Iterator listEntriesByType(byte code)

This will get all entries in the constant pool based on a specific type.

Parameters:

code - The type code used to search for entries.

getSize

public long getSize()

This will return the number of entries that are contained

getEntry

public ConstantPoolEntry getEntry(long index)

This will get an entry in the pool for you

isReady

public boolean isReady(long index)

This will tell you if the selected entry is ready to be read. This is only necessary while the pool is being created. If you read the first entry and it is a CONSTANT_Classref and it has as its data an index to a utf string, which might be at index 2, well we havn't read in number two yet, so the constant at number 2 will not be ready

Parameters:

index - The constant pool index

Returns:

A boolean flag if the constant pool entry has been initialized

toBytes

public byte[] toBytes()
               throws JavarIOException

This will get the constant pool as a set of bytes that are needed.

Returns:

the classfile bytes that represent this constant pool

JavarIOException

addString

public long addString(String entry)

This will add an entry to the constant pool.

Returns:

the index of that entry

addUTF8

public long addUTF8(String entry)

This will add an entry to the constant pool.

Returns:

the index of that entry

findUTF8

public long findUTF8(String string)

This will find the index to the string, or -1 if it was not found.

Parameters:

string - The string to find

Returns:

the index to the string

addClass

public long addClass(String className)

This will add an entry to the constant pool

Parameters:

className - The name of the class to add.

Returns:

the index where the class was stored.

addNameAndType

public long addNameAndType(String name,
                           String type)

This will add a name and type entry to the pool

Parameters:

name - The name

type - Thee type

Returns:

the index to this new entry

addMethod

public long addMethod(String className,
                      String name,
                      String type)

This will add a new method to the pool

Parameters:

className - The name of the class

name - The name of the method

type - Descriptor of the method

Returns:

the index to the method