Package org.aspectj.apache.bcel.classfile

Class Code

java.lang.Object

org.aspectj.apache.bcel.classfile.Attribute

org.aspectj.apache.bcel.classfile.Code

All Implemented Interfaces:

Serializable, 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 1.9 2009/10/05 17:35:36 aclement Exp $

Author:

M. Dahm

See Also:

• Attribute
• CodeException
• LineNumberTable
• LocalVariableTable
• Serialized Form

Field Summary

Fields inherited from class org.aspectj.apache.bcel.classfile.Attribute

cpool, length, nameIndex, NoAttributes, tag

Constructor Summary

Constructors

Constructor	Description
Code(int name_index, int length, int max_stack, int max_locals, byte[] code, CodeException[] exception_table, Attribute[] attributes, ConstantPool constant_pool)
Code(Code c)	Initialize from another object.

Method Summary

Modifier and Type	Method	Description
void	accept(ClassVisitor v)	Called by objects that are traversing the nodes of the tree implicitely defined by the contents of a Java class.
final void	dump(DataOutputStream file)	Dump code attribute to file stream in binary format.
final Attribute[]	getAttributes()
final byte[]	getCode()
String	getCodeString()	Returns the same as toString(true) except that the attribute information isn't included (line numbers).
final CodeException[]	getExceptionTable()
LineNumberTable	getLineNumberTable()
LocalVariableTable	getLocalVariableTable()
final int	getMaxLocals()
final int	getMaxStack()
final void	setAttributes(Attribute[] attributes)
final void	setCode(byte[] code)
final void	setExceptionTable(CodeException[] exception_table)
final void	setMaxLocals(int max_locals)
final void	setMaxStack(int max_stack)
final String	toString()
final String	toString(boolean verbose)

Methods inherited from class org.aspectj.apache.bcel.classfile.Attribute

getConstantPool, getLength, getName, getNameIndex, getTag, readAttribute

Methods inherited from class java.lang.Object

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

Constructor Details

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 Details

accept

public void accept(ClassVisitor 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

Specified by:

accept in class Attribute

Parameters:

v - Visitor object

dump

public final void dump(DataOutputStream file)
                throws IOException

Dump code attribute to file stream in binary format.

Overrides:

dump in class Attribute

Parameters:

file - Output file stream

Throws:

IOException

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 String toString(boolean verbose)

Returns:

String representation of code chunk.

toString

public final String toString()

Overrides:

toString in class Attribute

Returns:

String representation of code chunk.

getCodeString

public String getCodeString()

Returns the same as toString(true) except that the attribute information isn't included (line numbers). Can be used to check whether two pieces of code are equivalent.