gnu.bytecode

Class Variable

java.lang.Object

gnu.bytecode.Location

gnu.bytecode.Variable

All Implemented Interfaces:

java.util.Enumeration

public class Variable
extends Location
implements java.util.Enumeration

Information about a local variable in a method's code.

Field Summary

Fields

Modifier and Type	Field and Description
int	offset The local variable slot number used by this variable.

Fields inherited from class gnu.bytecode.Location

name

Constructor Summary

Constructors

Constructor and Description
Variable()
Variable(java.lang.String name)
Variable(java.lang.String name, Type type)

Method Summary

Modifier and Type	Method and Description
void	allocateLocal(CodeAttr code) Allocate slots for a local variable (or parameter).
boolean	dead()
void	freeLocal(CodeAttr code)
Scope	getScope()
boolean	hasMoreElements()
boolean	isAssigned() Returns true iff assigned to a local variable slot.
boolean	isParameter()
boolean	isSimple() Returns true for a "simple" variable.
java.lang.Object	nextElement()
Variable	nextVar()
boolean	reserveLocal(int varIndex, CodeAttr code) Assign a local variable to a given local variable slot.
void	setParameter(boolean parameter)
void	setSimple(boolean simple)
java.lang.String	toString()

Methods inherited from class gnu.bytecode.Location

getName, getSignature, getType, setName, setName, setSignature, setType

Methods inherited from class java.lang.Object

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

Field Detail

offset

public int offset

The local variable slot number used by this variable. Not used (by the codegen layer) if !isSimple().

Constructor Detail

Variable

public Variable()

Variable

public Variable(java.lang.String name)

Variable

public Variable(java.lang.String name,
                Type type)

Method Detail

nextVar

public final Variable nextVar()

hasMoreElements

public final boolean hasMoreElements()

Specified by:

hasMoreElements in interface java.util.Enumeration

nextElement

public java.lang.Object nextElement()

Specified by:

nextElement in interface java.util.Enumeration

isAssigned

public final boolean isAssigned()

Returns true iff assigned to a local variable slot. Only relevant if isSimple ().

getScope

public Scope getScope()

dead

public final boolean dead()

isSimple

public final boolean isSimple()

Returns true for a "simple" variable. A "simple" Variable can be stack-allocated using standard local variable slots. It is allocated by the codegen package. A non-simple variable may need heap allocation, or more more complex access; it is basically ignored by the codegen package, and must be managed by higher layers.

setSimple

public final void setSimple(boolean simple)

isParameter

public final boolean isParameter()

setParameter

public final void setParameter(boolean parameter)

reserveLocal

public boolean reserveLocal(int varIndex,
                            CodeAttr code)

Assign a local variable to a given local variable slot.

Parameters:

varIndex - the index of the local variables.

Returns:

true iff we succeeded (i.e. the slot was unused)

allocateLocal

public void allocateLocal(CodeAttr code)

Allocate slots for a local variable (or parameter).

freeLocal

public void freeLocal(CodeAttr code)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object