Java异常:java.net.UnknownHostException产生的原因和解决方案

import java.net.InetAddress;
import java.net.UnknownHostException;

public class UnknownHostExceptionExample {
    public static void main(String[] args) {
        String hostName = "nonexistent-host.com";

        try {
            InetAddress address = InetAddress.getByName(hostName);
            System.out.println("IP Address: " + address.getHostAddress());
        } catch (UnknownHostException e) {
            System.out.println("Exception: " + e.getMessage());
            e.printStackTrace();
        }
    }
}

import java.net.InetAddress;
import java.net.UnknownHostException;

public class HandleUnknownHostException {
    public static void main(String[] args) {
        String hostName = "nonexistent-host.com";

        try {
            InetAddress address = InetAddress.getByName(hostName);
            System.out.println("IP Address: " + address.getHostAddress());
        } catch (UnknownHostException e) {
            System.out.println("Exception: " + e.getMessage());

            // 1. 检查主机名拼写
            // 2. 检查网络连接
            // 3. 检查DNS配置
            // 4. 使用备用主机名或IP地址

            e.printStackTrace();
        }
    }
}

String hostName = "correct-host.com";

nameserver 8.8.8.8
nameserver 8.8.4.4

String hostName = "backup-host.com";
String ipAddress = "192.168.1.1";

try {
    InetAddress address = InetAddress.getByName(hostName);
    System.out.println("IP Address: " + address.getHostAddress());
} catch (UnknownHostException e) {
    try {
        InetAddress address = InetAddress.getByName(ipAddress);
        System.out.println("IP Address: " + address.getHostAddress());
    } catch (UnknownHostException ex) {
        System.out.println("Exception: " + ex.getMessage());
        ex.printStackTrace();
    }
}