Specification

Design, write and test a program that evaluates infix expressions of unsigned integers using two stacks. The main class will be P1GUI. It should create a Swing based GUI that allows the user input an infix expression and displays the result.

The GUI must be generated by code that you write. You may not use a drag-and-drop GUI generator. The GUI should look as follows:

Another class, InfixEval, should contain the code to perform the infix expression evaluation. For infix expression evaluation, two stacks will be used: a stack of operands and a stack of operators. The pseudocode for performing that evaluation is shown below:

tokenize the string containing the expression
while there are more tokens
get the next token
if it is an operand
push it onto the operand stack
else if it is a left parenthesis push it onto the operator stack
else if it is a right parenthesis
while top of the operator stack is not a left parenthesis
pop two operands and an operator perform the calculation
push the result onto the operand stack
pop top of the operator stack and ignore it (i.e. it is a left parenthesis) else if it is an operator
while the operator stack is not empty and
the operator at the top of the stack has higher
or the same precedence than the current operator
pop two operands and perform the calculation
push the result onto the operand stack
push the current operator on the operators stack
while the operator stack is not empty pop two operands and an operator perform the calculation
push the result onto the operand stack
the final result is at the top of the operand stack

Be sure to add any additional methods needed to eliminate any duplication of code.

Your program is only expected to perform correctly on syntactically correct infix expressions that contain integer operands and the four arithmetic operators + - * /. It should not, however, require spaces between tokens. The usual precedence rules apply. The division performed should be integer division. A check should be made for division by zero. Should the expression contain division by zero, a checked custom exception DivideByZero should be thrown by the method that performs the evaluation and caught in the main class, where a JOptionPane window should be displayed containing an error message.

Your program should compile without errors.

The Google recommended Java style guide should be used to format and document your code. Specifically, the following style guide attributes should be addressed: header comments include filename, author, date and brief purpose of the program; in-line comments used to describe major functionality of the code; the meaning and the role of variables and constants are indicated as code comments; meaningful variable names and prompts applied; class names are written in UpperCamelCase; variable names are written in lowerCamelCase; constant names are in written in All Capitals; braces use K&R style.

In addition, the following design constraints should be followed: declare all instance variables private; avoid the duplication of code.

2. Submission requirements

Submit the following to the Project 1 assignment area no later than the due date listed in your LEO classroom.

1. All .Java source files (no other file types should be submitted) and the output file generated by the program. The source code should use Java code conventions and appropriate code layout (white space management and indents) and comments. All submitted files may be included in a .zip file.

2. The solution description document P1SolutionDescription (.pdf or .doc / .docx) containing the following:

(1) Assumptions, main design and error handling;

(2) A UML class diagram that includes all classes you wrote. Do not include predefined classes. You need only include the class name for each individual class, not the variables or methods;

(3) A table of test cases including the test cases that you have created to test the program. The table should have 5 columns indicating (i) what aspect is tested, (ii) the input values, (iii) the expected output, (iv) the actual output and (v) if the test case passed or failed. Each test case will be defined in a table row.

(4) Relevant screenshots of program execution;

(5) Lessons learned from the project;