客服端-服务器模式
TCP/UDP
telnet下载网页
telnet获取网页过程
步骤1: telnet www.baidu.com 80(设置目标服务器, 端口号)
步骤2: GET /index.html HTTP/1.1
Host: www.baidu.com
步骤3:然后连续按两下enter键盘, 获取网页结果
再进一步,使用Java获取网页
BufferedWriter bw =null;
BufferedReader br = null;
// 步骤1 telnet www.baidu.com 80(设置目标服务器, 端口号)
Socket socket = new Socket(url,80);
// 步骤2
// GET /index.html HTTP/1.1
// Host: www.baidu.com
bw = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
bw.write("GET /"+ mainPage + " HTTP/1.1\r\n");
bw.write("HOST:" + url + "\r\n");
bw.write("\r\n");//HTTP head end!
bw.flush();
//步骤3
//然后连续按两下enter键盘, 获取网页结果
br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF-8"));
String line ;
while((line = br.readLine())!=null){
System.out.println(line);
}
if(bw != null){
bw.close();
}
if (br != null) {
br.close();
}
if(socket != null)
{
socket.close();
}