Boolean return value after evaluating javaScript code using javax.script.ScriptEngine object

I am using javax.script package. * to evaluate javascript in a Java file. I am using ScriptEngine object to evaluate javaScript code. The javaScript code returns a boolean. I'm not sure how to capture the boolean in a Java file. For example, see

import javax.script.*;
public class Test {
    public static void main(String[] args) throws Exception {
        ScriptEngineManager factory = new ScriptEngineManager();
        ScriptEngine engine = factory.getEngineByName("JavaScript");
        String filepath = "../test.js";
        engine.eval(new java.io.FileReader(filepath));
    }
}

      

        
        
        
      

    

test.js

function test(value) {
    if(value==1) {
       println("True");
       return true;
    } else {
       println("False");
       return false;
    }
}

var i=1;
test (i);

      

        
        
        
      

    

I tried the following:

Boolean result = (Boolean) engine.eval(new java.io.FileReader(filepath));

      

        
        
        
      

    

The above line throws a java.lang.NullPointerException error.

Thanks, Sony