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Call a Function - Java SDK

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  • Call a Function by Name

The examples in this section demonstrate calling a simple function named sum that takes two arguments, adds them, and returns the result:

// sum: adds two numbers
exports = function(a, b) {
  return a + b;
};

Call a Function by Name

To execute a function from the SDK, use the getFunctions() method of the your App to retrieve a Functions manager. Pass the name and parameters of the function you would like to call to callFunction() or callFunctionAsync():

String appID = YOUR_APP_ID; // replace this with your App ID
App app = new App(new AppConfiguration.Builder(appID).build());
Credentials credentials = Credentials.anonymous();
app.loginAsync(credentials, it -> {
    if (it.isSuccess()) {
        User user = app.currentUser();
        assert user != null;
        Functions functionsManager = app.getFunctions(user);
        List<Integer> args = Arrays.asList(1, 2);
        functionsManager.callFunctionAsync("sum", args, Integer.class, result -> {
            if (result.isSuccess()) {
                Log.v("EXAMPLE", "Sum value: " + result.get());
            } else {
                Log.e("EXAMPLE", "failed to call sum function with: " + result.getError());
            }
        });
    } else {
        Log.e("EXAMPLE", "Error logging into the Realm app. Make sure that anonymous authentication is enabled. Error: " + it.getError());
    }
});
val appID = YOUR_APP_ID // replace this with your App ID
val app: App = App(AppConfiguration.Builder(appID).build())
val anonymousCredentials: Credentials = Credentials.anonymous()
app.loginAsync(anonymousCredentials) {
    if (it.isSuccess) {
        val user: User? = app.currentUser()
        val functionsManager: Functions = app.getFunctions(user)
        val args: List<Int> = listOf(1, 2)
        functionsManager.callFunctionAsync("sum", args, Integer::class.java) { result ->
            if (result.isSuccess) {
                Log.v("EXAMPLE", "Sum value: ${result.get()}")
            } else {
                Log.e("EXAMPLE", "failed to call sum function with: " + result.error)
            }
        }
    } else {
        Log.e("EXAMPLE", "Error logging into the Realm app. Make sure that anonymous authentication is enabled. Error: " + it.error)
    }
}

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