How to get long value in lambda function?

Question

I am new here, and I hope that you will help me. I have a javascript function and there i call a function like this:

var criticalDateStart = new Date(1525683802394);
var criticalDateEnd = new Date(1525770202394);

var users = enumerateUsers({
    userId : userId,
    criticalDateStart : criticalDateStart.getTime(),
    criticalDateEnd : criticalDateEnd.getTime(),
});

Furthemore, I have a lambda function on the server, that looks like this:

Function<Object, Object> enumeratePatients = (arg) -> {

        if (arg instanceof ScriptObjectMirror) {
            ScriptObjectMirror _arg = (ScriptObjectMirror) arg;
            Integer userId = (Integer) _arg.get("userId");
            Long criticalDateStart = (Long)_arg.get("criticalDateStart");   
            Long criticalDateEnd = (Long)_arg.get("criticalDateEnd");

            ResteasyClient client = new ResteasyClientBuilder().build();
            ResteasyWebTarget rtarget = client.target(Url);
            Rest rest = rtarget.proxy(Rest.class);
                return rest.enumerateUsers(
                         new EnumerateUserParameter(
                           userId, 
                           criticalDateStart, 
                           criticalDateEnd));
            }
            return null;
        };

But it returns an error

java.lang.ClassCastException: java.lang.Double cannot be cast to java.lang.Long.

Where is the problem?

By the way, the error is at the long criticalDateStart and end line.

What framework are you using to communicate with the back end? — Ahmad Shahwan, May 22 '18 at 12:34
Is it possible to avoid casting?https://stackoverflow.com/questions/321549/how-to-convert-a-double-to-long-without-casting — dehasi, May 22 '18 at 12:35

score 0 · Answer 1 · answered May 22 '18 at 12:35

It looks like criticalDateStart and criticalDateEnd are doubles, not longs, in your Java code. What you can do:

long criticalDateStart = ((Double)_arg.get("criticalDateStart")).longValue();
long criticalDateEnd = ((Double)_arg.get("criticalDateEnd")).longValue();

score -1 · Accepted Answer · answered May 22 '18 at 12:36

-1

Try using Double's method longValue().

Long criticalDateStart = ((Double) _arg.get("criticalDateStart")).longValue();

answered May 22 '18 at 12:36

Ahmad Shahwan

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`ScriptObjectMirror` resolve your object as `Double`. While java can convert primitive double to primitive long, its not the case when using corresponding objects. This is simply because `Long` is not a subclass of `Double`. – Ahmad Shahwan May 22 '18 at 12:53
1

aha, ty, I get it now :) – May 22 '18 at 12:55

How to get long value in lambda function?

2 Answers2