// file: RoutingDemo.java

// Simulate AMQP-style direct vs topic routing with plain Java maps (no external deps).

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import java.util.*;

import java.util.function.Predicate;

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class Message { String key; String body; Message(String k, String b){ key=k; body=b; } }

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interface QueueLike { void push(Message m); List<Message> drain(); }

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class MemoryQueue implements QueueLike {

    private final LinkedList<Message> q = new LinkedList<>();

    public void push(Message m){ q.add(m); }

    public List<Message> drain(){ List<Message> out=new ArrayList<>(q); q.clear(); return out; }

}

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public class RoutingDemo {

    // Binding for "direct": exact match on routing key

    static Map<String, QueueLike> directBindings = new HashMap<>();

    // Binding for "topic": predicate over routing key (very simplified)

    static Map<Predicate<String>, QueueLike> topicBindings = new HashMap<>();

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    static void publishDirect(Message m){

        QueueLike q = directBindings.get(m.key);

        if(q!=null) q.push(m);

    }

    static void publishTopic(Message m){

        topicBindings.forEach((pred,q)->{ if(pred.test(m.key)) q.push(m); });

    }