Consumer based command system

README.md

Registering a command

register(new String[] { "test", "t", "ping" }, args -> {
    System.out.println("\nFired! Your args: " + Arrays.toString(args));
});

Running a command

handle("/test these are some of the command arguments!");

CommandBus.java

import java.util.*;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
import java.util.function.Consumer;

public class CommandBus {
​
    private final Map<String, List<Consumer<String[]>>> handlers = new HashMap<>();
    private final ReadWriteLock lock = new ReentrantReadWriteLock();
​
    public void register(String[] names, Consumer<String[]> consumer) {
        lock.writeLock().lock();
        try {
            List<Consumer<String[]>> list;
            if (handlers.containsKey(names)) {
                list = handlers.get(names);
            } else {
                list = new ArrayList<>();
            }
            list.add(consumer);
            
            for (String name : names) {
                handlers.put(name, list);
            }
        } finally {
            lock.writeLock().unlock();
        }
    }
​
    public void handle(String input) {
        if (!input.startsWith("/")) return;
        input = input.substring(1);
​
        String[] args = input.split(" ");
        String command = args[0];
        args = Arrays.copyOfRange(args, 1, args.length);
​
        lock.readLock().lock();
        try {
            if (!handlers.containsKey(command)) return;
            List<Consumer<String[]>> consumers = handlers.get(command);
            for (Consumer<String[]> consumer : consumers) {
                consumer.accept(args);
            }
        } finally {
            lock.readLock().unlock();
        }
    }
​
}