JCalc is a toy stack-based calculator written in Java. It was made to learn
the Swing API, not as a real project.
mvn install
java -jar target/JCalc-1.0.jar
Or double-click on the jar to open the app.
JCalc uses a stack, which means you can make complicated operations which
deal with priorities without using parentheses. To add the current value to the
stack, press the “push” button (<<). You can now type a new value, and either
push it on the stack or use one of the six simple operations.
An operation pop the top of the stack, applies itself on it and the current value (in that order), and replace the current value with the result.
You can reset everything at any time with the R button.
We want to compute (3+5)*(4-2). In the following table, the first column shows
the pressed button, the second one shows the resulting value and the last one
the internal stack (top on the right).
| Command | Result | Stack |
|---|---|---|
3 |
3 | - |
<< |
- | 3 |
5 |
5 | 3 |
+ |
8 | - |
<< |
- | 8 |
4 |
4 | 8 |
<< |
- | 8, 4 |
2 |
2 | 8, 4 |
- |
2 | 8 |
* |
16 | - |