Package net.ssehub.easy.varModel.cstEvaluation

Class ContextStack

java.lang.Object

net.ssehub.easy.varModel.cstEvaluation.ContextStack

class ContextStack
extends java.lang.Object

Realizes a context stack for evaluating nested self expressions.

Author:

Holger Eichelberger

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	ContextStack.StackFrame	Implements a poolable stack frame.

Field Summary

Fields

Modifier and Type	Field	Description
private int	currentStart
private static Pool<ContextStack.StackFrame>	POOL
private java.util.Stack<ContextStack.StackFrame>	stack

Constructor Summary

Constructors

Constructor	Description
ContextStack()

Method Summary

Modifier and Type	Method	Description
(package private) void	clear()	Clears the whole stack.
private void	ensureCapacity(IDecisionVariable var, ContextStack.StackFrame frame)	Ensures the capacity of a container variable.
(package private) Value	getSelfValue()	Returns the value for self in the current context.
(package private) void	pop()	Pops a context frame.
(package private) void	push()	Pushes an empty frame.
(package private) void	push(ContainerInitializer init)	Pushes a frame with given initializer.
(package private) void	push(EvaluationAccessor ex)	Pushes a context frame for the given expression.
(package private) void	setCompoundSlot(java.lang.String slot)	Sets the compound slot in the actual frame.
(package private) void	setContainerIndex(int index)	Sets the container index in the actual frame.
(package private) void	setContainerInitializer(ContainerInitializer init)	Sets the container initializer in the actual frame.
(package private) void	setVariable(DecisionVariableDeclaration var)	Sets the (top-level) variable in the actual frame.

Methods inherited from class java.lang.Object

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

Field Detail

POOL

private static final Pool<ContextStack.StackFrame> POOL

stack

private java.util.Stack<ContextStack.StackFrame> stack

currentStart

private int currentStart

Constructor Detail

ContextStack

ContextStack()

Method Detail

push

void push(EvaluationAccessor ex)

Pushes a context frame for the given expression.

Parameters:

ex - the expression (will not be released

push

void push()

Pushes an empty frame.

push

void push(ContainerInitializer init)

Pushes a frame with given initializer.

Parameters:

init - the initializer

See Also:

push(), setContainerIndex(int)

setVariable

void setVariable(DecisionVariableDeclaration var)

Sets the (top-level) variable in the actual frame. Requires push() before.

Parameters:

var - the variable

setContainerInitializer

void setContainerInitializer(ContainerInitializer init)

Sets the container initializer in the actual frame. Requires push() before.

Parameters:

init - the initializer

See Also:

push()

setContainerIndex

void setContainerIndex(int index)

Sets the container index in the actual frame. Requires push() before.

Parameters:

index - the index value

See Also:

push()

setCompoundSlot

void setCompoundSlot(java.lang.String slot)

Sets the compound slot in the actual frame. Requires push() before.

Parameters:

slot - the new slot

See Also:

push()

pop

void pop()

Pops a context frame.

clear

void clear()

Clears the whole stack.

getSelfValue

Value getSelfValue()

Returns the value for self in the current context.

Returns:

the expression for self

ensureCapacity

private void ensureCapacity(IDecisionVariable var,
                            ContextStack.StackFrame frame)

Ensures the capacity of a container variable.

Parameters:

var - the variable

frame - the stack frame with the access index to ensure fore