Package com.singularsys.extensions.structure

Class LoopNode

java.lang.Object

com.singularsys.jep.parser.SimpleNode

com.singularsys.extensions.structure.StructureNode

com.singularsys.extensions.structure.LoopNode

All Implemented Interfaces:

Node

public class LoopNode
extends StructureNode

A node represents a looping construct such as a for or while loop.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	LoopNode.ControlValues	Special values to indicate break and continue statements Used by ControlRule and ControlNode.

Nested classes/interfaces inherited from interface com.singularsys.jep.parser.Node

Node.HookKey

Field Summary

Fields inherited from class com.singularsys.jep.parser.SimpleNode

children, id, keys, parent, vals

Constructor Summary

Constructors

Constructor	Description
LoopNode(Node initializer, Node condition, Node increment, Node body)	Constructor.

Method Summary

Modifier and Type	Method	Description
Object	eval(Evaluator ev)	Evaluate the Loop.
Node	getBody()
Node	getCondition()
Node	getIncrement()
Node	getInitializer()
String	toString()

Methods inherited from class com.singularsys.extensions.structure.StructureNode

getName, getOperator, getPFMC, getValue, getVar, testCondition

Methods inherited from class com.singularsys.jep.parser.SimpleNode

childIterator, children, childrenAccept, dump, getChildren, getHook, getId, hookKeys, jjtAccept, jjtAddChild, jjtClose, jjtGetChild, jjtGetNumChildren, jjtGetParent, jjtOpen, jjtSetParent, removeHook, setHook, toString

Methods inherited from class java.lang.Object

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

Constructor Details

LoopNode

public LoopNode(Node initializer,
 Node condition,
 Node increment,
 Node body)

Constructor.

Parameters:

initializer - node evaluate at start of loop, can be null

condition - evaluated and tested before each evaluation, can be null

increment - evaluated after each iteration, can be null

body - evaluated once per iteration

Method Details

getInitializer

public Node getInitializer()

getCondition

public Node getCondition()

getIncrement

public Node getIncrement()

getBody

public Node getBody()

toString

public String toString()

Overrides:

toString in class Object

eval

public Object eval(Evaluator ev)
            throws EvaluationException

Evaluate the Loop.

1. First evaluate the initialisation (if given)
2. Evaluate the condition (if given), if result is false exit
3. Evaluate the body, if the result is break exit
5. Evaluate the increment (if given)
6. loop to 2

Specified by:

eval in class StructureNode

Parameters:

ev - The evaluator the Evaluator.eval(com.singularsys.jep.parser.Node) can be used to evaluate children.

Returns:

result of evaluation

Throws:

EvaluationException - if evaluation cannot be performed