使用smack 4.2.2从Openfire服务器获取所有用户

import org.jivesoftware.smack.AbstractXMPPConnection;
import org.jivesoftware.smack.ConnectionConfiguration;
import org.jivesoftware.smack.SmackException;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.tcp.XMPPTCPConnection;
import org.jivesoftware.smack.tcp.XMPPTCPConnectionConfiguration;

// 创建连接配置
XMPPTCPConnectionConfiguration config = XMPPTCPConnectionConfiguration.builder()
        .setHost("your_openfire_server_host")
        .setPort(5222)
        .setServiceName("your_openfire_service_name")
        .build();

// 创建连接
AbstractXMPPConnection connection = new XMPPTCPConnection(config);

// 连接到服务器
try {
    connection.connect();
} catch (SmackException | IOException | XMPPException e) {
    e.printStackTrace();
}

try {
    connection.login("your_username", "your_password");
} catch (SmackException | IOException | XMPPException e) {
    e.printStackTrace();
}

import org.jivesoftware.smack.roster.RosterEntry;
import org.jivesoftware.smack.roster.Roster;
import java.util.Collection;

// 获取花名册
Roster roster = Roster.getInstanceFor(connection);

// 获取所有用户
Collection<RosterEntry> entries = roster.getEntries();

// 遍历输出所有用户
for (RosterEntry entry : entries) {
    System.out.println("Username: " + entry.getUser());
}