Generator functions equivalent in Java

Had the same need so wrote a little class for it. Here are some examples:

Generator<Integer> simpleGenerator = new Generator<Integer>() {
    public void run() throws InterruptedException {
        yield(1);
        // Some logic here...
        yield(2);
    }
};
for (Integer element : simpleGenerator)
    System.out.println(element);
// Prints "1", then "2".

Infinite generators are also possible:

Generator<Integer> infiniteGenerator = new Generator<Integer>() {
    public void run() throws InterruptedException {
        while (true)
            yield(1);
    }
};

The Generator class internally works with a Thread to produce the items. By overriding finalize(), it ensures that no Threads stay around if the corresponding Generator is no longer used.

The performance is obviously not great but not too shabby either. On my machine with a dual core i5 CPU @ 2.67 GHz, 1000 items can be produced in < 0.03s.

The code is on GitHub. There, you’ll also find instructions on how to include it as a Maven/Gradle dependency.

Leave a Comment

tech