Java获取本机hostname的方法_Java获取外网IP地址的方法

在Java中获取本机hostname的方法有以下几种:

1. 使用InetAddress.getLocalHost().getHostName()方法:

InetAddress localHost = InetAddress.getLocalHost();
String hostname = localHost.getHostName();

2. 使用System.getenv("COMPUTERNAME")方法:

String hostname = System.getenv("COMPUTERNAME");

3. 使用System.getProperty("user.name")方法:

String hostname = System.getProperty("user.name");

在Java中获取外网IP地址的方法有以下几种:

1. 使用InetAddress.getLocalHost().getHostAddress()方法:

InetAddress localHost = InetAddress.getLocalHost();
String ip = localHost.getHostAddress();

2. 使用第三方API获取:

String url = "http://api.ipify.org";
BufferedReader in = new BufferedReader(new InputStreamReader(new URL(url).openStream()));
String ip = in.readLine();

3. 使用HttpURLConnection访问外部IP查询服务:

URL url = new URL("http://ip.42.pl/raw");
HttpURLConnection con = (HttpURLConnection) url.openConnection();
String ip = new BufferedReader(new InputStreamReader(con.getInputStream())).readLine();