Break or return from Java 8 stream forEach?

When using external iteration over an Iterable we use break or return from enhanced for-each loop as:

for (SomeObject obj : someObjects) {
   if (some_condition_met) {
      break; // or return obj
   }
}

How can we break or return using the internal iteration in a Java 8 lambda expression like:

someObjects.forEach(obj -> {
   //what to do here?
})
Jon Skeet
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Either you need to use a method which uses a predicate indicating whether to keep going (so it has the break instead) or you need to throw an exception - which is a very ugly approach, of course.

So you could write a forEachConditional method like this:

public static <T> void forEachConditional(Iterable<T> source,
                                          Predicate<T> action) {
    for (T item : source) {
        if (!action.test(item)) {
            break;
        }
    }
}

Rather than Predicate<T>, you might want to define your own functional interface with the same general method (something taking a T and returning a bool) but with names that indicate the expectation more clearly - Predicate<T> isn't ideal here.

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