Package com.offbynull.coroutines.instrumenter.asm

Class VariableTable

java.lang.Object

com.offbynull.coroutines.instrumenter.asm.VariableTable

public final class VariableTable
extends java.lang.Object

Tracks extra variables used for instrumentation as well as arguments passed in to a method.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	VariableTable.Variable	Represents an entry within the local variable table of a method.

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.List<VariableTable.Variable>	argVars
private int	extraOffset
private java.util.List<VariableTable.Variable>	extraVars

Constructor Summary

Constructors

Modifier	Constructor	Description
private	VariableTable(boolean isStatic, org.objectweb.asm.Type objectType, org.objectweb.asm.Type methodType, int maxLocals)
	VariableTable(org.objectweb.asm.tree.ClassNode classNode, org.objectweb.asm.tree.MethodNode methodNode)	Constructs a VariableTable object.

Method Summary

Modifier and Type	Method	Description
VariableTable.Variable	acquireExtra(java.lang.Class<?> type)	Equivalent to calling acquireExtra(Type.getType(type)).
VariableTable.Variable	acquireExtra(org.objectweb.asm.Type type)	Acquire a new variable for use when instrumenting some code within the method this VariableTable is for.
int	getArgCount()	Get number of arguments.
VariableTable.Variable	getArgument(int index)	Get the variable for an argument passed in to the method.
void	releaseExtra(VariableTable.Variable variable)	Release a variable that was acquired with acquireExtra(org.objectweb.asm.Type).

Methods inherited from class java.lang.Object

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

Field Detail

argVars

private java.util.List<VariableTable.Variable> argVars

extraOffset

private int extraOffset

extraVars

private java.util.List<VariableTable.Variable> extraVars

Constructor Detail

VariableTable

public VariableTable(org.objectweb.asm.tree.ClassNode classNode,
                     org.objectweb.asm.tree.MethodNode methodNode)

Constructs a VariableTable object.

Parameters:

classNode - class that methodeNode resides in

methodNode - method this variable table is for

VariableTable

private VariableTable(boolean isStatic,
                      org.objectweb.asm.Type objectType,
                      org.objectweb.asm.Type methodType,
                      int maxLocals)

Method Detail

getArgument

public VariableTable.Variable getArgument(int index)

Get the variable for an argument passed in to the method. Remember that if the method is static, arguments start at 0th index in the local variables table. If it isn't static, they start at 1 (0th would be "this").

Values returned by this method must never be passed in to releaseExtra(com.offbynull.coroutines.instrumenter.asm.VariableTable.Variable).

Parameters:

index - index of argument

Returns:

VariableTable.Variable object that represents the argument

Throws:

java.lang.IllegalArgumentException - if index is not the index of an argument

acquireExtra

public VariableTable.Variable acquireExtra(java.lang.Class<?> type)

Equivalent to calling acquireExtra(Type.getType(type)).

Parameters:

type - type which variable is for

Returns:

new variable

Throws:

java.lang.NullPointerException - if any argument is null

acquireExtra

public VariableTable.Variable acquireExtra(org.objectweb.asm.Type type)

Acquire a new variable for use when instrumenting some code within the method this VariableTable is for.

Parameters:

type - type which variable is for

Returns:

new variable

Throws:

java.lang.NullPointerException - if any argument is null

java.lang.IllegalArgumentException - if type is of sort of Type.VOID or Type.METHOD

releaseExtra

public void releaseExtra(VariableTable.Variable variable)

Release a variable that was acquired with acquireExtra(org.objectweb.asm.Type).

Parameters:

variable - variable to release

Throws:

java.lang.NullPointerException - if any argument is null

java.lang.IllegalArgumentException - if variable wasn't acquired from this object, or if variable refers to an argument, or if variable has already been released

getArgCount

public int getArgCount()

Get number of arguments.

Returns:

number of arguments