myUtil

Class SyntaxTree

java.lang.Object

myUtil.SyntaxTree

public class SyntaxTree
extends java.lang.Object

This is class that will store the syntax tree of the input arithmetic express in a binary tree where both value and operators are String data in the tree nodes. rewrite 4/6/2017

Author:

Chung-Chih Li

Constructor Summary

Constructors

Constructor and Description
SyntaxTree(java.lang.String exp) Build up the syntax tree of the input arithmetic expression.

Method Summary

Modifier and Type	Method and Description
double	evaluate()
java.lang.String	infix()
java.lang.String	postfix()
java.lang.String	prefix()

Methods inherited from class java.lang.Object

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

Constructor Detail

SyntaxTree

public SyntaxTree(java.lang.String exp)
           throws java.lang.ArithmeticException

Build up the syntax tree of the input arithmetic expression.

Parameters:

exp - is a String of arithmetic expression in infix notation, e.g. "2+2+3".

Throws:

java.lang.ArithmeticException - ("Illegal Expression") if the input string is not a valid arithmetic expression.

Method Detail

evaluate

public double evaluate()
                throws java.lang.ArithmeticException

Returns:

a double which is the value of the arithmetic expression

Throws:

java.lang.ArithmeticException - ("Divided by zero") if divided by 0;

infix

public java.lang.String infix()

Returns:

the infix notation of the arithmetic expression, where each item is separated by a space.

prefix

public java.lang.String prefix()

Returns:

the prefix notation of the arithmetic expression, where each item is separated by a space.

postfix

public java.lang.String postfix()

Returns:

the postfix notation of the arithmetic expression, where each item is separated by a space.