Блог

Ниже приводится мой Demo.java код для грамматики, который я написал для некоторого выдуманного языка под названием LOOL. Теперь вместо того, чтобы напрямую указывать строку (например, так: CharStream input = new ANTLRStringStream («некоторый случайный код LOOL»); ) Я хочу иметь возможность загружать текстовый файл для сканирования, но не уверен, как это сделать. Любая помощь очень ценится. Спасибо. Моя демонстрация.Java-код:

 import org.antlr.runtime.*;

class Demo{

  public static void main(String[] args) throws Exception{
    CharStream input = new ANTLRStringStream("sample.lool");
    lool scanner = new lool(input);
        while(true){
        Token token = scanner.nextToken();
                if(token.getType() == Token.EOF )
            break;
        else if(token.getType()==scanner.ID)
            System.out.print("ID ");
        else if(token.getType() == scanner.IF)
            System.out.print(token.getText()  " ");
        else if(token.getType() == scanner.MODULE)
            System.out.print("MODULE ");
        else if(token.getType()== scanner.CHILDOF)
            System.out.println("CHILDOF ");
        else if(token.getType()== scanner.VIRTUAL)
            System.out.println("VIRTUAL ");
        else if(token.getType()== scanner.CREATE)
            System.out.println("CREATE ");
        else if(token.getType()== scanner.CHILDOF)
            System.out.println("CHILDOF ");
        else if(token.getType()== scanner.INT_LIT)
            System.out.println("INT_LIT ");
        else if(token.getType()== scanner.VOID)
            System.out.println("VOID ");
        else if(token.getType()== scanner.AND)
            System.out.println("AND ");
        else if(token.getType()== scanner.OR)
            System.out.println("OR ");
        else if(token.getType()== scanner.NOT)
            System.out.println("NOT ");
        else if(token.getType()== scanner.BOOL_LIT)
            System.out.println(scanner.BOOL_LIT);
        else if(token.getType()== scanner.RETURN)
            System.out.println("RETURN ");
        else if(token.getType()== scanner.IF)
            System.out.println("IF ");
        else if(token.getType()== scanner.THEN)
            System.out.println("THEN ");
        else if(token.getType()== scanner.ENDIF)
            System.out.println("ENDIF ");
        else if(token.getType()== scanner.WHILE)
            System.out.println("WHILE ");
        else if(token.getType()== scanner.LOOP)
            System.out.println("LOOP ");
        else if(token.getType()== scanner.ENDLOOP)
            System.out.println("ENDLOOP ");
        else if(token.getType()== scanner.BREAK)
            System.out.println("BREAK ");
        else if(token.getType()== scanner.CONTINUE)
            System.out.println("CONTINUE ");
        else if(token.getType()== scanner.READ)
            System.out.println("READ ");
        else if(token.getType()== scanner.WRITE)
            System.out.println("WRITE ");
        else if(token.getType()== scanner.INT_LIT)
            System.out.println("INT_LIT ");
        else if(token.getType()== scanner.BOOL_LIT)
            System.out.println("BOOL_LIT ");
        else if(token.getType()== scanner.STRING_LIT)
            System.out.println("STRING_LIT ");
        else if(token.getType()== scanner.SL_COMMENT)
            System.out.println("SingleLineComment ");
        else if(token.getType()== scanner.ML_COMMENT)
            System.out.println("MultiLineComment ");
        else if(token.getType()== scanner.ADD_OP)
            System.out.println("   ");
        else if(token.getType()== scanner.SUB_OP)
            System.out.println(" - ");
        else if(token.getType()== scanner.MULT_OP)
            System.out.println(" * ");
        else if(token.getType()== scanner.DIV_OP)
            System.out.println(" / ");
        else if(token.getType()== scanner.ASSIGN_OP)
            System.out.println(" =: ");
        else if(token.getType()== scanner.COLON)
            System.out.println(" : ");
        else if(token.getType()== scanner.LT_OP)
            System.out.println(" < ");
        else if(token.getType()== scanner.GT_OP)
            System.out.println(" > ");
        else if(token.getType()== scanner.LT_EQ_OP)
            System.out.println(" <= ");
        else if(token.getType()== scanner.GT_EQ_OP)
            System.out.println(" >= ");
        else if(token.getType()== scanner.EQ_OP)
            System.out.println(" = ");
        else if(token.getType()== scanner.NOT_EQ_OP)
            System.out.println(" != ");
        else if(token.getType()== scanner.SEPARATE)
            System.out.println(", ");
        else if(token.getType()== scanner.ACCESS)
            System.out.println(scanner.ACCESS);
        else if(token.getType()== scanner.ACCESS_ARRAY)
            System.out.println(scanner.ACCESS_ARRAY);
        else if(token.getType()== scanner.METHOD_PRECEDENCE)
            System.out.println(scanner.METHOD_PRECEDENCE);
        else if(token.getType()== scanner.MOD_BLOCK)
            System.out.println(scanner.MOD_BLOCK);
        else if(token.getType()== scanner.SEMICOLON)
            System.out.println(";");
        else if(token.getType()== scanner.ACCESS)
            System.out.println(".");


        else if(token.getType()== scanner.ERR1)
            System.out.println("ERR1("   token.getText()   ") ");

        else if(token.getType()== scanner.ERR2)
            System.out.println( "Err2("   token.getText()   ')' );

        else if(token.getType()== scanner.ERR3)
            System.out.println("ERR3");




    }
  }
}
  

Вместо

 CharStream input = new ANTLRStringStream("sample.lool");
  

вы хотите что-то, используя подкласс ANTLRFileStream sub class

 CharStream input = new ANTLRFileStream(new File("sample.lool"));