Question

I am using Javascript engine to compare values. Values can be double or date. (strings)

ScriptEngineManager factory = new ScriptEngineManager();
ScriptEngine engine = factory.getEngineByName("JavaScript");
// Date value is populated dynamically here
engine.eval("dateValue = " + "01/02/2012");
// The condition is populated dynamically here
if ((Boolean) engine.eval("dateValue <=" + "12/31/2012")) { 
  System.out.println("TRUE");
} else {
    System.out.println("FALSE");
}

The above code works fine with double values, but gives wrong results with dates. For the above example it should display TRUE, but it displays FALSE. Please help.

Answer 1

You should do something like:

engine.eval("var dateValue = " + "new Date(2012, 02, 01);");
...
if ((Boolean) "dateValue <=" + " new Date(2012, 12, 31);")

In your script 12/31/2012 will be interpreted as a mathematical expression.

another possibility for the test you wanna do is something like:

engine.eval("var test = dateValue <=" + " new Date(2012, 12, 31);")
Object myBoolean = engine.get("test");