NichtHaskell/Source/Compiler.java

import abstractSyntaxTree.Class.FieldDecl;
import abstractSyntaxTree.Class.MethodDecl;
import abstractSyntaxTree.Class.RefType;
import abstractSyntaxTree.Program;
import gen.DecafLexer;
import gen.DecafParser;
import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.CharStreams;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.Token;
import org.antlr.v4.runtime.tree.ParseTree;

import java.io.CharArrayReader;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;

public class Compiler {

    public static void main(String[] args) throws Exception{

        // get file
//        String filePath = "EmptyClass.java";
//        String content = new String(Files.readAllBytes(Paths.get(filePath)));
//        CharArrayReader charStream = new CharArrayReader(content.toCharArray());

        CharStream codeCharStream = CharStreams.fromString("class Example { int i; }");
        DecafLexer lexer = new DecafLexer(codeCharStream);
        CommonTokenStream tokens = new CommonTokenStream(lexer);

        System.out.println("--- print tokens ---");
        tokens.fill();

        List<Token> tokenList = tokens.getTokens();

        StringBuilder stringBuilder = new StringBuilder();
        for (Token token : tokenList) {
            stringBuilder.append(token.getText()).append(" ");
        }
        String readableTokens = stringBuilder.toString().trim();

        System.out.println(readableTokens);


        DecafParser parser = new DecafParser(tokens);

        ParseTree tree = parser.program();

        System.out.println("--- print tree ---");
        System.out.println(tree);



        Program abstractSyntaxTree = new Program(new ArrayList<>());

        abstractSyntaxTree.typeCheck();

        abstractSyntaxTree.codeGen();
    }
}