de.fub.bytecode.classfile
Class Code

java.lang.Object
  |
  +--de.fub.bytecode.classfile.Attribute
        |
        +--de.fub.bytecode.classfile.Code

All Implemented Interfaces:

java.lang.Cloneable, Node

public final class Code

extends Attribute

This class represents a chunk of Java byte code contained in a method. It is instantiated by the Attribute.readAttribute() method. A Code attribute contains informations about operand stack, local variables, byte code and the exceptions handled within this method. This attribute has attributes itself, namely LineNumberTable which is used for debugging purposes and LocalVariableTable which contains information about the local variables.

Version:

$Id: Code.java,v 1.4 2001/06/25 07:58:16 dahm Exp $

Author:

M. Dahm

See Also:

Attribute, CodeException, LineNumberTable, LocalVariableTable

Fields inherited from class de.fub.bytecode.classfile.Attribute

constant_pool, length, name_index, tag

Constructor Summary

Code(Code c)
Initialize from another object.

Code(int name_index, int length, int max_stack, int max_locals, byte[] code, CodeException[] exception_table, Attribute[] attributes, ConstantPool constant_pool)

Method Summary

void	accept(Visitor v) Called by objects that are traversing the nodes of the tree implicitely defined by the contents of a Java class.
Attribute	copy(ConstantPool constant_pool)
void	dump(java.io.DataOutputStream file) Dump code attribute to file stream in binary format.
Attribute[]	getAttributes()
byte[]	getCode()
CodeException[]	getExceptionTable()
LineNumberTable	getLineNumberTable()
LocalVariableTable	getLocalVariableTable()
int	getMaxLocals()
int	getMaxStack()
void	setAttributes(Attribute[] attributes)
void	setCode(byte[] code)
void	setExceptionTable(CodeException[] exception_table)
void	setMaxLocals(int max_locals)
void	setMaxStack(int max_stack)
java.lang.String	toString()
java.lang.String	toString(boolean verbose)

Methods inherited from class de.fub.bytecode.classfile.Attribute

clone, getConstantPool, getLength, getNameIndex, getTag, setConstantPool, setLength, setNameIndex

Methods inherited from class java.lang.Object

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

Constructor Detail

Code

public Code(Code c)

Initialize from another object. Note that both objects use the same references (shallow copy). Use copy() for a physical copy.

Code

public Code(int name_index,
            int length,
            int max_stack,
            int max_locals,
            byte[] code,
            CodeException[] exception_table,
            Attribute[] attributes,
            ConstantPool constant_pool)

Parameters:

name_index - Index pointing to the name Code

length - Content length in bytes

max_stack - Maximum size of stack

max_locals - Number of local variables

code - Actual byte code

exception_table - Table of handled exceptions

attributes - Attributes of code: LineNumber or LocalVariable

constant_pool - Array of constants

Method Detail

accept

public 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.

Overrides:

accept in class Attribute

Parameters:

v - Visitor object

dump

public final void dump(java.io.DataOutputStream file)
                throws java.io.IOException

Dump code attribute to file stream in binary format.

Overrides:

dump in class Attribute

Parameters:

file - Output file stream

getAttributes

public final Attribute[] getAttributes()

Returns:

Collection of code attributes.

See Also:

Attribute

getLineNumberTable

public LineNumberTable getLineNumberTable()

Returns:

LineNumberTable of Code, if it has one

getLocalVariableTable

public LocalVariableTable getLocalVariableTable()

Returns:

LocalVariableTable of Code, if it has one

getCode

public final byte[] getCode()

Returns:

Actual byte code of the method.

getExceptionTable

public final CodeException[] getExceptionTable()

Returns:

Table of handled exceptions.

See Also:

CodeException

getMaxLocals

public final int getMaxLocals()

Returns:

Number of local variables.

getMaxStack

public final int getMaxStack()

Returns:

Maximum size of stack used by this method.

setAttributes

public final void setAttributes(Attribute[] attributes)

Parameters:

attributes. -

setCode

public final void setCode(byte[] code)

Parameters:

code - byte code

setExceptionTable

public final void setExceptionTable(CodeException[] exception_table)

Parameters:

exception_table - exception table

setMaxLocals

public final void setMaxLocals(int max_locals)

Parameters:

max_locals - maximum number of local variables

setMaxStack

public final void setMaxStack(int max_stack)

Parameters:

max_stack - maximum stack size

toString

public final java.lang.String toString(boolean verbose)

Returns:

String representation of code chunk.

toString

public final java.lang.String toString()

Overrides:

toString in class Attribute

Returns:

String representation of code chunk.

copy

public Attribute copy(ConstantPool constant_pool)

Overrides:

copy in class Attribute

Returns:

deep copy of this attribute