Java Programming

Hello every one
when i tried to call javascript from java i faced an exception

My java code:

import java.io.FileReader;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;

public class WinClose {
  public static void main(String[] args) {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    try {
      FileReader reader = new FileReader("file.js");
      engine.eval(reader);
      reader.close();
    } catch (Exception e) {
      e.printStackTrace();
    }
  }
}

and my file.js is

function close(){
javascript:window.close();
}
close();
print ('Done !!');

the exception is:

javax.script.ScriptException: sun.org.mozilla.javascript.internal.EcmaError: ReferenceError: "alert" is not defined. (<Unknown source>#3) in <Unknown source> at line number 3
at com.sun.script.javascript.RhinoScriptEngine.eval(Unknown Source)
at javax.script.AbstractScriptEngine.eval(Unknown Source)
at WinClose.main(WinClose.java:12)

if any one can help my !!!
Thx