Question

Is it possible to access an instance of a variable in one class from another class in Java.

Let’s say you have the following in Class A:

private BlockingQueue<byte[]> buffer = new LinkedBlockingQueue<byte[]>();

I want to make changes to the queue in this class and then be able to use to access it from another class.

How would i access the instance of buffer from another class? Is it even possible?

Answer 1

Add a getter:

public class Whatever {

    private BlockingQueue<byte[]> buffer = new LinkedBlockingQueue<byte[]>();

    public BlockingQueue<byte[]> getBuffer() {
        return buffer;
    }
}

Then if you have an instance of Whatever:

Whatever w = new Whatever();
BlockingQueue<byte[]> buffer = w.getBuffer();