java网络编程

public static void main(String[] args) throws UnknownHostException {
    InetAddress locAdd = InetAddress.getLocalHost();
    InetAddress biaduAdd = InetAddress.getByName("www.baidu.com");

    System.out.println("我的Ip地址"+locAdd.getHostAddress());
    System.out.println("本地主机名"+locAdd.getHostName());
    System.out.println("百度的Ip地址"+biaduAdd.getHostAddress());
    try {
        System.out.println("本机是否可达"+locAdd.isReachable(2000));
    } catch (IOException e) {
        e.printStackTrace();
    }
}

• try { //指定操作的url URL url = new URL("http","www.mldnjava.cn",80,"/index.html"); InputStream input = url.openStream(); Scanner sc = new Scanner(input); sc.useDelimiter("\n");//设置读取分隔符 while(sc.hasNext()){ System.out.println(sc.next()); } } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }

• try { URL url1 = new URL("http://www.mldnjava.cn"); try { URLConnection urlc = url1.openConnection(); System.out.println("内容的大小"+urlc.getContentLength()); System.out.println("内容的类型"+urlc.getContentType()); System.out.println("内容的编码"+urlc.getContentEncoding()); } catch (IOException e) { e.printStackTrace(); } } catch (MalformedURLException e) { e.printStackTrace(); }

        String keyword = "hello 所有人";
        try {
            String encode = URLEncoder.encode(keyword,"UTF-8");
            System.out.println("after encoding====="+encode);
            String decode = URLDecoder.decode(encode,"UTF-8");
            System.out.println("after docode====="+decode);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

运行结果：

　　　　　　//after encoding=====hello+%E6%89%80%E6%9C%89%E4%BA%BA
　　　　　　//after docode=====hello 所有人

public class HelloServer {
    public static void main(String[] args) {
        ServerSocket server = null;
        Socket client = null;
        PrintStream out =null;
        try {
            server = new ServerSocket(8888);
            System.out.println("服务器运行，等待客户端连接");
            client =server.accept();
            String str = "hello World";
            out = new PrintStream(client.getOutputStream());
            out.println(str);
            out.close();
            client.close();
            server.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
}

public class HelloClient {
    public static void main(String[] args) throws IOException {
        Socket client = new Socket("localhost",8888);
        BufferedReader buf = null;
        buf = new BufferedReader(
                new InputStreamReader(
                        client.getInputStream()));
        String str = buf.readLine();
        System.out.println("服务器端输出内容："+str);
        client.close();
        buf.close();
    }
}