willow-utils/src/main/java/com/btr/proxy/selector/pac/ScriptAvailability.java
public static boolean isJavaxScriptingAvailable() {
    Object engine = null;
    try {
      Class<?> managerClass = Class.forName("javax.script.ScriptEngineManager");
      Method m = managerClass.getMethod("getEngineByMimeType", String.class);
      engine = m.invoke(managerClass.newInstance(), "text/javascript");
    } catch (ClassNotFoundException | NoSuchMethodException
        | IllegalAccessException | InvocationTargetException
        | InstantiationException e) {
      return false;
    }

    return engine != null;
  }
public static boolean isJavaxScriptingAvailable() {
    Object engine = null;
    try {
      Class<?> managerClass = Class.forName("javax.script.ScriptEngineManager");
      Method m = managerClass.getMethod("getEngineByMimeType", String.class);
      engine = m.invoke(managerClass.newInstance(), "text/javascript");
    } catch (ClassNotFoundException | NoSuchMethodException
        | IllegalAccessException | InvocationTargetException
        | InstantiationException e) {
      return false;
    }

    return engine != null;
  }
***********************************************************************
Checks whether javax.script is available or not. Completely done per
Reflection to allow compilation under Java 1.5

@return true if javax.script is available; false otherwise
**********************************************************************