slogo.instruction

Class Product

java.lang.Object

slogo.GrammarElement

slogo.instruction.Instruction

slogo.instruction.Product

public class Product
extends Instruction

A PRODUCT instruction has two components: two GrammarElements that represents the two numbers to perform multiplication on. To evaluate a PRODUCT instruction the expressions are evaluated first, this determines the double version of the numbers. The two numbers are multiplied and the product is returned.

The value returned by evaluating a PRODUCT instruction is the instruction itself, followed by the two expressions

Field Summary

Fields

Modifier and Type	Field and Description
private GrammarElement	expressionOne
private GrammarElement	expressionTwo
private java.lang.Double	total

Fields inherited from class slogo.GrammarElement

gelementsToValue

Constructor Summary

Constructors

Constructor and Description
Product(GrammarElement e, GrammarElement f) Constructs a PRODUCT instruction that can be executed.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	evaluate(Context c) Evaluate this instruction in a Context.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

expressionOne

private GrammarElement expressionOne

expressionTwo

private GrammarElement expressionTwo

total

private java.lang.Double total

Constructor Detail

Product

public Product(GrammarElement e,
               GrammarElement f)

Constructs a PRODUCT instruction that can be executed.

Parameters:

e - the first number

f - the second number

Method Detail

evaluate

public java.lang.Object evaluate(Context c)

Evaluate this instruction in a Context.

Specified by:

evaluate in class Instruction

Parameters:

c - the Context for the evaluation

Returns:

the total after multiplication

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

a String representing this instruction as PRODUCT, followed by the two expressions