How to check if element exists using a lambda expression?

java java-8 lambda
Miljac picture Miljac · Apr 11, 2014 · Viewed 136.5k times · Source

Specifically, I have TabPane, and I would like to know if there is element with specific ID in it.

So, I would like to do this with lambda expression in Java:

boolean idExists = false;
String idToCheck = "someId";

for (Tab t : tabPane.getTabs()){
    if(t.getId().equals(idToCheck)) {
        idExists = true;
    }
}

Answer

Masudul picture Masudul · Apr 11, 2014

Try to use anyMatch of Lambda Expression. It is much better approach.

 boolean idExists = tabPane.getTabs().stream()
            .anyMatch(t -> t.getId().equals(idToCheck));

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