org.apache.bcel.generic
Class ConstantPoolGen

java.lang.Object
  org.apache.bcel.generic.ConstantPoolGen

All Implemented Interfaces:

java.io.Serializable

public class ConstantPoolGen
extends java.lang.Object
implements java.io.Serializable

This class is used to build up a constant pool. The user adds constants via `addXXX' methods, `addString', `addClass', etc.. These methods return an index into the constant pool. Finally, `getFinalConstantPool()' returns the constant pool built up. Intermediate versions of the constant pool can be obtained with `getConstantPool()'. A constant pool has capacity for Constants.MAX_SHORT entries. Note that the first (0) is used by the JVM and that Double and Long constants need two slots.

Version:

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

Author:

M. Dahm

See Also:

Constant, Serialized Form

Nested Class Summary

private static class

ConstantPoolGen.Index

Field Summary

private java.util.Map	class_table
protected Constant[]	constants
private java.util.Map	cp_table
private static java.lang.String	FIELDREF_DELIM
private static java.lang.String	IMETHODREF_DELIM
protected int	index
private static java.lang.String	METHODREF_DELIM
private java.util.Map	n_a_t_table
private static java.lang.String	NAT_DELIM
protected int	size
private java.util.Map	string_table
private java.util.Map	utf8_table

Constructor Summary

ConstantPoolGen()
Create empty constant pool.

ConstantPoolGen(Constant[] cs)
Initialize with given array of constants.

ConstantPoolGen(ConstantPool cp)
Initialize with given constant pool.

Method Summary

int	addArrayClass(ArrayType type) Add a reference to an array class (e.g.
private int	addClass_(java.lang.String clazz)
int	addClass(ObjectType type) Add a new Class reference to the ConstantPool for a given type.
int	addClass(java.lang.String str) Add a new Class reference to the ConstantPool, if it is not already in there.
int	addConstant(Constant c, ConstantPoolGen cp) Import constant from another ConstantPool and return new index.
int	addDouble(double n) Add a new double constant to the ConstantPool, if it is not already in there.
int	addFieldref(java.lang.String class_name, java.lang.String field_name, java.lang.String signature) Add a new Fieldref constant to the ConstantPool, if it is not already in there.
int	addFloat(float n) Add a new Float constant to the ConstantPool, if it is not already in there.
int	addInteger(int n) Add a new Integer constant to the ConstantPool, if it is not already in there.
int	addInterfaceMethodref(MethodGen method)
int	addInterfaceMethodref(java.lang.String class_name, java.lang.String method_name, java.lang.String signature) Add a new InterfaceMethodref constant to the ConstantPool, if it is not already in there.
int	addLong(long n) Add a new long constant to the ConstantPool, if it is not already in there.
int	addMethodref(MethodGen method)
int	addMethodref(java.lang.String class_name, java.lang.String method_name, java.lang.String signature) Add a new Methodref constant to the ConstantPool, if it is not already in there.
int	addNameAndType(java.lang.String name, java.lang.String signature) Add a new NameAndType constant to the ConstantPool if it is not already in there.
int	addString(java.lang.String str) Add a new String constant to the ConstantPool, if it is not already in there.
int	addUtf8(java.lang.String n) Add a new Utf8 constant to the ConstantPool, if it is not already in there.
protected void	adjustSize() Resize internal array of constants.
Constant	getConstant(int i)
ConstantPool	getConstantPool()
ConstantPool	getFinalConstantPool()
int	getSize()
int	lookupClass(java.lang.String str) Look for ConstantClass in ConstantPool named `str'.
int	lookupDouble(double n) Look for ConstantDouble in ConstantPool.
int	lookupFieldref(java.lang.String class_name, java.lang.String field_name, java.lang.String signature) Look for ConstantFieldref in ConstantPool.
int	lookupFloat(float n) Look for ConstantFloat in ConstantPool.
int	lookupInteger(int n) Look for ConstantInteger in ConstantPool.
int	lookupInterfaceMethodref(MethodGen method)
int	lookupInterfaceMethodref(java.lang.String class_name, java.lang.String method_name, java.lang.String signature) Look for ConstantInterfaceMethodref in ConstantPool.
int	lookupLong(long n) Look for ConstantLong in ConstantPool.
int	lookupMethodref(MethodGen method)
int	lookupMethodref(java.lang.String class_name, java.lang.String method_name, java.lang.String signature) Look for ConstantMethodref in ConstantPool.
int	lookupNameAndType(java.lang.String name, java.lang.String signature) Look for ConstantNameAndType in ConstantPool.
int	lookupString(java.lang.String str) Look for ConstantString in ConstantPool containing String `str'.
int	lookupUtf8(java.lang.String n) Look for ConstantUtf8 in ConstantPool.
void	setConstant(int i, Constant c) Use with care!
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

size

protected int size

constants

protected Constant[] constants

index

protected int index

METHODREF_DELIM

private static final java.lang.String METHODREF_DELIM

See Also:

Constant Field Values

IMETHODREF_DELIM

private static final java.lang.String IMETHODREF_DELIM

See Also:

Constant Field Values

FIELDREF_DELIM

private static final java.lang.String FIELDREF_DELIM

See Also:

Constant Field Values

NAT_DELIM

private static final java.lang.String NAT_DELIM

See Also:

Constant Field Values

string_table

private java.util.Map string_table

class_table

private java.util.Map class_table

utf8_table

private java.util.Map utf8_table

n_a_t_table

private java.util.Map n_a_t_table

cp_table

private java.util.Map cp_table

Constructor Detail

ConstantPoolGen

public ConstantPoolGen(Constant[] cs)

Initialize with given array of constants.

Parameters:

cs - array of given constants, new ones will be appended

ConstantPoolGen

public ConstantPoolGen(ConstantPool cp)

Initialize with given constant pool.

ConstantPoolGen

public ConstantPoolGen()

Create empty constant pool.

Method Detail

adjustSize

protected void adjustSize()

Resize internal array of constants.

lookupString

public int lookupString(java.lang.String str)

Look for ConstantString in ConstantPool containing String `str'.

Parameters:

str - String to search for

Returns:

index on success, -1 otherwise

addString

public int addString(java.lang.String str)

Add a new String constant to the ConstantPool, if it is not already in there.

Parameters:

str - String to add

Returns:

index of entry

lookupClass

public int lookupClass(java.lang.String str)

Look for ConstantClass in ConstantPool named `str'.

Parameters:

str - String to search for

Returns:

index on success, -1 otherwise

addClass_

private int addClass_(java.lang.String clazz)

addClass

public int addClass(java.lang.String str)

Add a new Class reference to the ConstantPool, if it is not already in there.

Parameters:

str - Class to add

Returns:

index of entry

addClass

public int addClass(ObjectType type)

Add a new Class reference to the ConstantPool for a given type.

Parameters:

type - Class to add

Returns:

index of entry

addArrayClass

public int addArrayClass(ArrayType type)

Add a reference to an array class (e.g. String[][]) as needed by MULTIANEWARRAY instruction, e.g. to the ConstantPool.

Parameters:

type - type of array class

Returns:

index of entry

lookupInteger

public int lookupInteger(int n)

Look for ConstantInteger in ConstantPool.

Parameters:

n - integer number to look for

Returns:

index on success, -1 otherwise

addInteger

public int addInteger(int n)

Add a new Integer constant to the ConstantPool, if it is not already in there.

Parameters:

n - integer number to add

Returns:

index of entry

lookupFloat

public int lookupFloat(float n)

Look for ConstantFloat in ConstantPool.

Parameters:

n - Float number to look for

Returns:

index on success, -1 otherwise

addFloat

public int addFloat(float n)

Add a new Float constant to the ConstantPool, if it is not already in there.

Parameters:

n - Float number to add

Returns:

index of entry

lookupUtf8

public int lookupUtf8(java.lang.String n)

Look for ConstantUtf8 in ConstantPool.

Parameters:

n - Utf8 string to look for

Returns:

index on success, -1 otherwise

addUtf8

public int addUtf8(java.lang.String n)

Add a new Utf8 constant to the ConstantPool, if it is not already in there.

Parameters:

n - Utf8 string to add

Returns:

index of entry

lookupLong

public int lookupLong(long n)

Look for ConstantLong in ConstantPool.

Parameters:

n - Long number to look for

Returns:

index on success, -1 otherwise

addLong

public int addLong(long n)

Add a new long constant to the ConstantPool, if it is not already in there.

Parameters:

n - Long number to add

Returns:

index of entry

lookupDouble

public int lookupDouble(double n)

Look for ConstantDouble in ConstantPool.

Parameters:

n - Double number to look for

Returns:

index on success, -1 otherwise

addDouble

public int addDouble(double n)

Add a new double constant to the ConstantPool, if it is not already in there.

Parameters:

n - Double number to add

Returns:

index of entry

lookupNameAndType

public int lookupNameAndType(java.lang.String name,
                             java.lang.String signature)

Look for ConstantNameAndType in ConstantPool.

Parameters:

name - of variable/method

signature - of variable/method

Returns:

index on success, -1 otherwise

addNameAndType

public int addNameAndType(java.lang.String name,
                          java.lang.String signature)

Add a new NameAndType constant to the ConstantPool if it is not already in there.

Parameters:

name - Name string to add

signature - signature string to add

Returns:

index of entry

lookupMethodref

public int lookupMethodref(java.lang.String class_name,
                           java.lang.String method_name,
                           java.lang.String signature)

Look for ConstantMethodref in ConstantPool.

Parameters:

class_name - Where to find method

method_name - Guess what

signature - return and argument types

Returns:

index on success, -1 otherwise

lookupMethodref

public int lookupMethodref(MethodGen method)

addMethodref

public int addMethodref(java.lang.String class_name,
                        java.lang.String method_name,
                        java.lang.String signature)

Add a new Methodref constant to the ConstantPool, if it is not already in there.

Parameters:

class_name - class name string to add

method_name - method name string to add

signature - method signature string to add

Returns:

index of entry

addMethodref

public int addMethodref(MethodGen method)

lookupInterfaceMethodref

public int lookupInterfaceMethodref(java.lang.String class_name,
                                    java.lang.String method_name,
                                    java.lang.String signature)

Look for ConstantInterfaceMethodref in ConstantPool.

Parameters:

class_name - Where to find method

method_name - Guess what

signature - return and argument types

Returns:

index on success, -1 otherwise

lookupInterfaceMethodref

public int lookupInterfaceMethodref(MethodGen method)

addInterfaceMethodref

public int addInterfaceMethodref(java.lang.String class_name,
                                 java.lang.String method_name,
                                 java.lang.String signature)

Add a new InterfaceMethodref constant to the ConstantPool, if it is not already in there.

Parameters:

class_name - class name string to add

method_name - method name string to add

signature - signature string to add

Returns:

index of entry

addInterfaceMethodref

public int addInterfaceMethodref(MethodGen method)

lookupFieldref

public int lookupFieldref(java.lang.String class_name,
                          java.lang.String field_name,
                          java.lang.String signature)

Look for ConstantFieldref in ConstantPool.

Parameters:

class_name - Where to find method

field_name - Guess what

signature - return and argument types

Returns:

index on success, -1 otherwise

addFieldref

public int addFieldref(java.lang.String class_name,
                       java.lang.String field_name,
                       java.lang.String signature)

Add a new Fieldref constant to the ConstantPool, if it is not already in there.

Parameters:

class_name - class name string to add

field_name - field name string to add

signature - signature string to add

Returns:

index of entry

getConstant

public Constant getConstant(int i)

Parameters:

i - index in constant pool

Returns:

constant pool entry at index i

setConstant

public void setConstant(int i,
                        Constant c)

Use with care!

Parameters:

i - index in constant pool

c - new constant pool entry at index i

getConstantPool

public ConstantPool getConstantPool()

Returns:

intermediate constant pool

getSize

public int getSize()

Returns:

current size of constant pool

getFinalConstantPool

public ConstantPool getFinalConstantPool()

Returns:

constant pool with proper length

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

String representation.

addConstant

public int addConstant(Constant c,
                       ConstantPoolGen cp)

Import constant from another ConstantPool and return new index.