Headers एक्सचेंज का गहन अध्ययन

import com.rabbitmq.client.*;
import java.util.HashMap;
import java.util.Map;

public class HeadersProducer {
    private static final String EXCHANGE = "my_headers_exchange";

    public static void main(String[] argv) throws Exception {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        try (Connection conn = factory.newConnection();
             Channel channel = conn.createChannel()) {

            channel.exchangeDeclare(EXCHANGE, "headers");

            Map<String, Object> headers = new HashMap<>();
            headers.put("format", "json");
            headers.put("type", "report"); // Add headers

            String msg = "Report Data (JSON)";
            AMQP.BasicProperties props = new AMQP.BasicProperties.Builder()
                                            .headers(headers)
                                            .build();
            channel.basicPublish(EXCHANGE, "", props, msg.getBytes("UTF-8"));
            System.out.println(" [x] Sent: '" + msg + "' with headers: " + headers);
        }
    }
}

import com.rabbitmq.client.*;
import java.util.HashMap;
import java.util.Map;

public class HeadersConsumerAll {
    private static final String EXCHANGE = "my_headers_exchange";

    public static void main(String[] argv) throws Exception {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection conn = factory.newConnection();
        Channel channel = conn.createChannel();

        channel.exchangeDeclare(EXCHANGE, "headers");
        String queueName = channel.queueDeclare().getQueue();

        Map<String, Object> bindHeaders = new HashMap<>();
        bindHeaders.put("x-match", "all");
        bindHeaders.put("format", "json");
        bindHeaders.put("type", "report"); // Requires both

        channel.queueBind(queueName, EXCHANGE, "", bindHeaders);
        System.out.println(" [*] Waiting for msgs with ALL: " + bindHeaders);

        DeliverCallback dc = (ct, delivery) -> {
            String msg = new String(delivery.getBody(), "UTF-8");
            System.out.println(" [x] Received '" + msg + "' Headers: " + delivery.getProperties().getHeaders());
        };
        channel.basicConsume(queueName, true, dc, ct -> {});
    }
}

import com.rabbitmq.client.*;
import java.util.HashMap;
import java.util.Map;

public class HeadersConsumerAny {
    private static final String EXCHANGE = "my_headers_exchange";

    public static void main(String[] argv) throws Exception {
        ConnectionFactory factory = new ConnectionFactory();
        factory.setHost("localhost");
        Connection conn = factory.newConnection();
        Channel channel = conn.createChannel();

        channel.exchangeDeclare(EXCHANGE, "headers");
        String queueName = channel.queueDeclare().getQueue();

        Map<String, Object> bindHeaders = new HashMap<>();
        bindHeaders.put("x-match", "any");
        bindHeaders.put("format", "xml"); // Matches if format is xml
        bindHeaders.put("priority", "high"); // OR if priority is high

        channel.queueBind(queueName, EXCHANGE, "", bindHeaders);
        System.out.println(" [*] Waiting for msgs with ANY: " + bindHeaders);

        DeliverCallback dc = (ct, delivery) -> {
            String msg = new String(delivery.getBody(), "UTF-8");
            System.out.println(" [x] Received '" + msg + "' Headers: " + delivery.getProperties().getHeaders());
        };
        channel.basicConsume(queueName, true, dc, ct -> {});
    }
}