1. 使用 Spotify 的 Java 客户端库，在项目中添加以下依赖：

    com.spotify
    docker-client
    8.16.0

2. 创建一个服务发现类，该类负责查询 Docker Swarm 集群中运行的服务：

import com.spotify.docker.client.DockerClient;
import com.spotify.docker.client.DockerClient.ListServicesParam;
import com.spotify.docker.client.DockerClient.ListTasksParam;
import com.spotify.docker.client.DockerClient.ListTasksParamBuilder;
import com.spotify.docker.client.exceptions.DockerCertificateException;
import com.spotify.docker.client.exceptions.DockerException;
import com.spotify.docker.client.messages.swarm.Service;
import com.spotify.docker.client.messages.swarm.Task;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class DockerSwarmServiceDiscovery {
    
    private final DockerClient dockerClient;
    
    public DockerSwarmServiceDiscovery() throws DockerCertificateException {
        this.dockerClient = DefaultDockerClient.fromEnv().build();
    }
    
    public List getServiceEndpoints(String serviceName) {
        try {
            final List services = this.dockerClient.listServices(ListServicesParam.create().serviceName(serviceName)).stream().filter(s -> s.spec().name().equals(serviceName)).collect(Collectors.toList());
            final List endpoints = new ArrayList<>();
            
            for (Service service : services) {
                final ListTasksParamBuilder tasksParamBuilder = ListTasksParam.builder().serviceId(service.id());
                
                final List tasks = this.dockerClient.listTasks(tasksParamBuilder.build());
                
                for (Task task : tasks) {
                    endpoints.add(String.format("%s:%d", task.status().containerStatus().containerId(), task.status().containerStatus().ports().get(0).publicPort()));
                }
            }
            
            return endpoints;
        } catch (DockerException | InterruptedException e) {
            throw new RuntimeException("Error providing service endpoints", e);
        }
    }
}

3. 在需要使用服务的代码中，实例化上述服务发现类并查询指定服务的 IP 和端口：

final DockerSwarmService