com.singularsys.jep.functions
Interface CallbackEvaluationI
- All Known Implementing Classes:
- AbstractInc, Assign, Case, If, LazyLogical, NullLazyLogical, NullWrappedIf, OpEquals, PostDec, PostInc, PreDec, PreInc, Switch, SwitchDefault
public interface CallbackEvaluationI
Functions which require greater control over their evaluation should implement this interface.
- Author:
- Rich Morris
Created on 18-Nov-2003
Method Summary |
java.lang.Object |
evaluate(Node node,
Evaluator pv)
Performs some special evaluation on the node. |
evaluate
java.lang.Object evaluate(Node node,
Evaluator pv)
throws EvaluationException
- Performs some special evaluation on the node.
This method has the responsibility for evaluating the children of the node
and it should generally call
pv.eval(node.jjtGetChild(i))
for each child.
The SymbolTable is not passed as an argument. This is because
it is better practice to get and set variable values by using
node.getVar().setValue() rather that through the SymbolTable with
requires a hashtable lookup.
- Parameters:
node
- The current nodepv
- The visitor, can be used evaluate the children
- Returns:
- the value after evaluation. This value will be passed to other
functions higher up the node tree. The value can be any type including Double or Vector<Object>
- Throws:
EvaluationException
- See Also:
Evaluator
Copyright © 2010 Singular Systems http://www.singularsys.com/jep