Channel Buffering in Fortress

In Java, we don’t have an exact equivalent of Go’s buffered channels. However, we can use a BlockingQueue to achieve similar functionality. Here’s how we can implement the concept:

import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;

public class ChannelBuffering {
    public static void main(String[] args) throws InterruptedException {
        // Here we create a BlockingQueue of strings with a capacity of 2.
        BlockingQueue<String> messages = new LinkedBlockingQueue<>(2);

        // Because this queue is buffered, we can add these
        // values into the queue without a corresponding
        // concurrent receive.
        messages.put("buffered");
        messages.put("channel");

        // Later we can receive these two values as usual.
        System.out.println(messages.take());
        System.out.println(messages.take());
    }
}

By default, BlockingQueue implementations in Java are unbounded, meaning they can grow as needed. However, by specifying a capacity when creating the LinkedBlockingQueue, we create a bounded queue that accepts a limited number of elements.

The put method is used to add elements to the queue. If the queue is full, put will block until space becomes available. This is similar to sending on a buffered channel in Go.

The take method is used to remove and return elements from the queue. If the queue is empty, take will block until an element becomes available. This is similar to receiving from a channel in Go.

To run the program:

$ javac ChannelBuffering.java
$ java ChannelBuffering
buffered
channel

This example demonstrates how to use a BlockingQueue in Java to achieve functionality similar to buffered channels in Go. While the syntax and exact behavior differ, the core concept of buffering a limited number of values remains the same.