log.illsley.org

I’ve been thinking a fair bit about server side JavaScript recently, but haven’t really dug in. One of the things I’ve been wondering is how easy it is to define a host object with Rhino. Turns out it’s trivial:

import org.mozilla.javascript.Context;
import org.mozilla.javascript.ScriptableObject;
public class Test {
public static class TestHost extends ScriptableObject {
  private String val = "";
  public String getClassName() {
    return "TestHost";
  }
  public String jsGet_val() {
    return val;
  }
  public void jsSet_val(String s) {
    val = s;
    System.out.println("from java: " + s);
  }
}

public static void main(String args[]) throws Exception {
  Context c = Context.enter();
  ScriptableObject so = c.initStandardObjects();
  ScriptableObject.defineClass(so, TestHost.class);
  System.out.println(c.evaluateString(so,
      "var t = new TestHost(); t.val='ee';'from script: '+t.val", "",
      1, null));
  }
}

Results in:

from java: ee
from script: ee