martinezlucas98 / java2cpp

FLEX & BISON Java to C++ translator. NOTICE: it is still under development.

🐲 java2cpp

FLEX & BISON Java to C++ translator.

⚠️ Warning: java2cpp is still under development and constant changes.

👀 Full 50+ pages documentation available in 🇪🇸Spanish🇲🇽 here.

Documentation

Quick Start

Simply pipe your input file into the translator executable a.out :

./a.out < YOUR_PATH_TO_FILE/FILE.java

Compiling Lex And Yacc

Make sure you've installed flex and bison on your system.

If you choose to modify the lex java2cpp.l or yacc java2cpp.y files, you would need to step through the following commands in the terminal to update your file changes.

First you should run:

lex java2cpp.l

Second:

yacc java2cpp.y

Third and last:

cc y.tab.c -ly -ll

Then you can run java2cpp as stated on the quick start section.

Contributing

You are more than welcome to help java2cpp become more robust by adding new features, fixing bugs, improving the documentations, and a lot more.

All you need to do is fork this repo and begin coding! 🎉

Please read the contributing guide to learn about our contributing rules and standards.

java2cpp's Issues

Save result in a .cc file

No impirmir el codigo, sino guardar en un archivo

Accept and detect constant variables

Title

Description:

A clear description of the issue.
Describe the solution you'd like.
Describe alternatives you've considered.

Additional context:

Add any other context or screenshots about the feature request here.

Bug: variables are printed within [ ]

Bug: variables are printed within [ ]

Description:

When a variable is detected as part of an expression it is printed within [ ]

To Reproduce:

Steps to reproduce the behavior:

1. Create a input file, for example testing.java as follows:

public class Main {
  public static void main(String[] args) {
    int a =3+6;
    int b = a+2;
  }
}

2. Execute java2cpp
3. Error - the translation results in:

int main(int argc, char **argv){
        int a = 3+6;
        int b = [a]+2;

}

Expected behavior:

The translation should be:

int main(int argc, char **argv){
        int a = 3+6;
        int b = a+2;

}

implement array parameter with fix value

Implement while and do-while

Implement while and do while

Description:

The translator has no grammar for the while and do-while loops. These are major features that must be added.
The followings must be implemented:

• 1. while loop grammar
• 2. do while loop grammar

Implement symbol table and "variable not declared" error

Implement symbol table and "variable not declared" error

Description:
An error message must be printed when a "variable not declared" or "variable not declared in scope" error occurs.
For now we will implement Panic-Mode Error Recovery. This can be upgraded in the future.

Translate method with params

Full support for the for loop

Full support for the for loop

Description:

java2cpp translator does not support for loop grammar at the moment. This grammar must be implemented.
The followings must be implemented:

• 1. Classic C style for loop
• 2. For-each loop

Implement Syntax Error

Implement Syntax Error

Description:
An error message must be printed when a syntax error occurs.
For now we will implement Panic-Mode Error Recovery. This can be upgraded in the future.

Define method scope

Title

Description:

A clear description of the issue.
Describe the solution you'd like.
Describe alternatives you've considered.

Additional context:

Add any other context or screenshots about the feature request here.

Full support for the if-else statement

Full support for the if-else statement

Description:

java2cpp translator does not support if-else grammar at the moment. This grammar must be implemented.
The followings must be implemented:

• 1. if-else grammar
• 2. if-else if grammar
• 3. if-else if - else grammar
• 4. Embedded if-else statements

Implement print function grammar

Print function grammar

Description:

The most common function is the print function, this is a MUST HAVE for any translator.
The following grammars must be added:

• System.out.println(expr); -----> std::cout << expr << std::endl;
• System.out.print(expr); -----> std::cout << expr ;

Implement declaration of array

Required support for Java declarations:

• double[ ] arr1 = new int[5];
• int[ ] arr2 = {5,4,3,2,1};
• double[ ][ ] arr3 = new int[3][5];
• int[ ][ ] arr4 = {{1,2,3},{4,5,6},{7,8,9}};

Implement Type Error

Implement Type Error

Description:
An error message must be printed when a type error occurs.
For now we will implement Panic-Mode Error Recovery. This can be upgraded in the future.

Text input function grammar

Text input function grammar

Description:

The following translations are needed and must be added:

• Scanner my_input = new Scanner(System.in); -----> string my_input; std::cin >> my_input;
• my_input = new Scanner(System.in); -----> std::cin >> my_input;