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Expression Handling

I intended to post the whole Java source code but unfortunately, there are 8 files in total so I think it will be better if you get them from MediaFire. Don't worry, there are only ~500 lines of code and I wrote comment for every single method.

Actually, the main class (Expression) design isn't done by me 100% because I have to follow the assignment requirement (also in the uploaded file). I don't really understand why we have to have 2 constructors and then another append() method. Really, I can't get it. Tell me if you have an idea.

Anyway, using the Expression class is very simple. Here is how I tested it:



Please note that it will run but an Exception will be thrown about variable b hasn't been initialized yet. You can either remove b from the append() method or use setValue() method to assign an value for the variable.

Also note that: currently the class support adding, subtracting, multiplying and dividing. Functions can be supported easily by writing a new class (ExpressionFunction?) and change the RPNize() static method (using Shunting-yard algorithm) a little bit. All comments are welcome. Thank you for reading

Comments

  1. What about comment of an outsider? Have no idea what all this is about but seems you are having your inspiration again. Keep up the attitude dear :*

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