org.gibello.zql.data
Class ZEval

java.lang.Object
  org.gibello.zql.data.ZEval

public class ZEval
extends java.lang.Object

Evaluate SQL expressions

Constructor Summary

ZEval()

Method Summary

boolean	eval(ZTuple tuple, ZExp exp) Evaluate a boolean expression to true or false (for example, SQL WHERE clauses are boolean expressions)
java.lang.Object	evalExpValue(ZTuple tuple, ZExp exp) Evaluate a numeric or string expression (example: a+1)
static void	main(java.lang.String[] args)

Methods inherited from class java.lang.Object

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

Constructor Detail

ZEval

public ZEval()

Method Detail

eval

public boolean eval(ZTuple tuple,
                    ZExp exp)
             throws java.sql.SQLException

Evaluate a boolean expression to true or false (for example, SQL WHERE clauses are boolean expressions)

Parameters:

tuple - The tuple on which to evaluate the expression

exp - The expression to evaluate

Returns:

true if the expression evaluate to true for this tuple, false if not.

Throws:

java.sql.SQLException

evalExpValue

public java.lang.Object evalExpValue(ZTuple tuple,
                                     ZExp exp)
                              throws java.sql.SQLException

Evaluate a numeric or string expression (example: a+1)

Parameters:

tuple - The tuple on which to evaluate the expression

exp - The expression to evaluate

Returns:

The expression's value

Throws:

java.sql.SQLException

main

public static void main(java.lang.String[] args)