Package serp.bytecode.lowlevel

Class ConstantPool

java.lang.Object

serp.bytecode.lowlevel.ConstantPool

All Implemented Interfaces:

VisitAcceptor

public class ConstantPool
extends java.lang.Object
implements VisitAcceptor

A bytecode constant pool, containing entries for all strings, constants, classes, etc referenced in the class structure and method opcodes. In keeping with the low-level bytecode representation, all pool indexes are 1-based and LongEntrys and DoubleEntrys each occupy two indexes in the pool.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	ConstantPool.ClassKey	Key for class entries.
private static class	ConstantPool.DoublePtrKey	Base class key for entries with two ptr to other entries.
private static class	ConstantPool.FieldKey	Key for field entries.
private static class	ConstantPool.InterfaceMethodKey	Key for interface method entries.
private static class	ConstantPool.InvokeDynamicKey	Key for method entries.
private static class	ConstantPool.MethodKey	Key for method entries.
private static class	ConstantPool.NameAndTypeKey	Key for name and type entries.
private static class	ConstantPool.PtrKey	Base class key for entries with one ptr to another entry.
private static class	ConstantPool.StringKey	Key for string entries.

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.List	_entries
private java.util.Map	_lookup

Constructor Summary

Constructors

Constructor	Description
ConstantPool()	Default constructor.

Method Summary

Modifier and Type	Method	Description
void	acceptVisit(BCVisitor visit)	Accept a visit from a BCVisitor, calling the appropriate methods to notify the visitor that it has entered this entity, and to provide it with the proper callbacks for each sub-entity owned by this one.
private int	addEntry(java.lang.Object key, Entry entry)	Add an entry to the pool using the given key.
int	addEntry(Entry entry)	Add an entry to the pool.
void	clear()	Clear all entries from the pool.
private int	find(java.lang.Object key)	Returns the constant pool index of the entry with the given key.
int	findClassEntry(java.lang.String name, boolean add)	Return the constant pool index of the ClassEntry for the given class name, or 0 if it does not exist.
private int	findComplexEntry(java.lang.String owner, java.lang.String name, java.lang.String desc, int type, boolean add)	Return the constant pool index of the ComplexEntry for the given name, descriptor, and owner class name.
int	findDoubleEntry(double value, boolean add)	Return the constant pool index of the DoubleEntry for the given value, or 0 if it does not exist.
int	findFieldEntry(java.lang.String owner, java.lang.String name, java.lang.String desc, boolean add)	Return the constant pool index of the FieldEntry for the given name, descriptor, and owner class name.
int	findFloatEntry(float value, boolean add)	Return the constant pool index of the FloatEntry for the given value, or 0 if it does not exist.
int	findIntEntry(int value, boolean add)	Return the constant pool index of the IntEntry for the given value, or 0 if it does not exist.
int	findInterfaceMethodEntry(java.lang.String owner, java.lang.String name, java.lang.String desc, boolean add)	Return the constant pool index of the InterfaceMethodEntry for the given name, descriptor, and owner class name.
int	findInvokeDynamicEntry(int bootstrapMethodIndex, java.lang.String name, java.lang.String desc, boolean add)
int	findLongEntry(long value, boolean add)	Return the constant pool index of the LongEntry for the given value, or 0 if it does not exist.
int	findMethodEntry(java.lang.String owner, java.lang.String name, java.lang.String desc, boolean add)	Return the constant pool index of the MethodEntry for the given name, descriptor, and owner class name.
int	findNameAndTypeEntry(java.lang.String name, java.lang.String desc, boolean add)	Return the constant pool index of the NameAndTypeEntry for the given name and descriptor, or 0 if it does not exist.
int	findStringEntry(java.lang.String value, boolean add)	Return the constant pool index of the StringEntry for the given string value, or 0 if it does not exist.
int	findUTF8Entry(java.lang.String value, boolean add)	Return the index of the UTF8Entry with the given value, or 0 if it does not exist.
Entry[]	getEntries()	Return all the entries in the pool.
Entry	getEntry(int index)	Retrieve the entry at the specified 1-based index.
(package private) static java.lang.Object	getKey(Entry entry)	Return the hash key used for the specified entry.
int	indexOf(Entry entry)	Return the index of the given entry, or 0 if it is not in the pool.
(package private) void	modifyEntry(java.lang.Object origKey, Entry entry)	Called by constant pool entries when they are mutated.
void	read(java.io.DataInput in)	Fill the constant pool from the given bytecode stream.
boolean	removeEntry(Entry entry)	Remove the given entry from the pool.
int	size()	Return the number of places occupied in the pool, including the fact that long and double entries occupy two places.
void	write(java.io.DataOutput out)	Write the constant pool to the given bytecode stream.

Methods inherited from class java.lang.Object

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

Field Detail

_entries

private java.util.List _entries

_lookup

private java.util.Map _lookup

Constructor Detail

ConstantPool

public ConstantPool()

Default constructor.

Method Detail

getEntries

public Entry[] getEntries()

Return all the entries in the pool.

getEntry

public Entry getEntry(int index)

Retrieve the entry at the specified 1-based index.

Throws:

java.lang.IndexOutOfBoundsException - if index is invalid, including the case that it points to the second slot of a long or double entry

indexOf

public int indexOf(Entry entry)

Return the index of the given entry, or 0 if it is not in the pool.

addEntry

public int addEntry(Entry entry)

Add an entry to the pool.

Returns:

the index at which the entry was added

addEntry

private int addEntry(java.lang.Object key,
                     Entry entry)

Add an entry to the pool using the given key.

removeEntry

public boolean removeEntry(Entry entry)

Remove the given entry from the pool.

Returns:

false if the entry is not in the pool, true otherwise

clear

public void clear()

Clear all entries from the pool.

size

public int size()

Return the number of places occupied in the pool, including the fact that long and double entries occupy two places.

findUTF8Entry

public int findUTF8Entry(java.lang.String value,
                         boolean add)

Return the index of the UTF8Entry with the given value, or 0 if it does not exist.

Parameters:

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findDoubleEntry

public int findDoubleEntry(double value,
                           boolean add)

Return the constant pool index of the DoubleEntry for the given value, or 0 if it does not exist.

Parameters:

value - the value to find

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findFloatEntry

public int findFloatEntry(float value,
                          boolean add)

Return the constant pool index of the FloatEntry for the given value, or 0 if it does not exist.

Parameters:

value - the value to find

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findIntEntry

public int findIntEntry(int value,
                        boolean add)

Return the constant pool index of the IntEntry for the given value, or 0 if it does not exist.

Parameters:

value - the value to find

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findLongEntry

public int findLongEntry(long value,
                         boolean add)

Return the constant pool index of the LongEntry for the given value, or 0 if it does not exist.

Parameters:

value - the value to find

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findStringEntry

public int findStringEntry(java.lang.String value,
                           boolean add)

Return the constant pool index of the StringEntry for the given string value, or 0 if it does not exist.

Parameters:

value - the value to find

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findClassEntry

public int findClassEntry(java.lang.String name,
                          boolean add)

Return the constant pool index of the ClassEntry for the given class name, or 0 if it does not exist.

Parameters:

name - the class name in internal form

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findNameAndTypeEntry

public int findNameAndTypeEntry(java.lang.String name,
                                java.lang.String desc,
                                boolean add)

Return the constant pool index of the NameAndTypeEntry for the given name and descriptor, or 0 if it does not exist.

Parameters:

name - the name of the entity

desc - the descriptor of the entity in internal form

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findFieldEntry

public int findFieldEntry(java.lang.String owner,
                          java.lang.String name,
                          java.lang.String desc,
                          boolean add)

Return the constant pool index of the FieldEntry for the given name, descriptor, and owner class name.

Parameters:

owner - the name of the field's owning class in internal form

name - the name of the field

desc - the descriptor of the field in internal form

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findMethodEntry

public int findMethodEntry(java.lang.String owner,
                           java.lang.String name,
                           java.lang.String desc,
                           boolean add)

Return the constant pool index of the MethodEntry for the given name, descriptor, and owner class name.

Parameters:

owner - the name of the method's owning class in internal form

name - the name of the method

desc - the descriptor of the method in internal form

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findInterfaceMethodEntry

public int findInterfaceMethodEntry(java.lang.String owner,
                                    java.lang.String name,
                                    java.lang.String desc,
                                    boolean add)

Return the constant pool index of the InterfaceMethodEntry for the given name, descriptor, and owner class name.

Parameters:

owner - the name of the method's owning class in internal form

name - the name of the method

desc - the descriptor of the method in internal form

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

findInvokeDynamicEntry

public int findInvokeDynamicEntry(int bootstrapMethodIndex,
                                  java.lang.String name,
                                  java.lang.String desc,
                                  boolean add)

findComplexEntry

private int findComplexEntry(java.lang.String owner,
                             java.lang.String name,
                             java.lang.String desc,
                             int type,
                             boolean add)

Return the constant pool index of the ComplexEntry for the given name, descriptor, and owner class name.

Parameters:

owner - the name of the owning class in internal form

name - the name of the entity

desc - the descriptor of the entity in internal form

type - the type of entry: field, method, interface method

add - if true, the entry will be added if it does not already exist, and the new entry's index returned

acceptVisit

public void acceptVisit(BCVisitor visit)

Description copied from interface: VisitAcceptor

Accept a visit from a BCVisitor, calling the appropriate methods to notify the visitor that it has entered this entity, and to provide it with the proper callbacks for each sub-entity owned by this one.

Specified by:

acceptVisit in interface VisitAcceptor

read

public void read(java.io.DataInput in)
          throws java.io.IOException

Fill the constant pool from the given bytecode stream.

Throws:

java.io.IOException

write

public void write(java.io.DataOutput out)
           throws java.io.IOException

Write the constant pool to the given bytecode stream.

Throws:

java.io.IOException

modifyEntry

void modifyEntry(java.lang.Object origKey,
                 Entry entry)

Called by constant pool entries when they are mutated.

find

private int find(java.lang.Object key)

Returns the constant pool index of the entry with the given key.

getKey

static java.lang.Object getKey(Entry entry)

Return the hash key used for the specified entry.