Question

所以我的作业就像标题所示。获取一个URL，从中获取主机名和路径名，然后打开一个套接字并写入/读取它。我已经分割了网址并尝试制作套接字：

    try {
        Socket socket = new Socket(hostname, port);
        InputStream inStream = socket.getInputStream();
        DataOutputStream outStream = new DataOutputStream(socket.getOutputStream());

        outStream.writeChars(pathname);
        outStream.flush();
    }
    catch (Exception e) {
        System.out.println(e);
    }

然后我尝试了很多方法来获得响应，例如我使用过：

BufferedInputStream in = new BufferedInputStream(socket.getInputStream());  

OutputStream out = new BufferedOutputStream(new FileOutputStream(new File("test.txt")));  
byte[] buf = new byte[256];  
int n = 0;  
while ((n=in.read(buf))>=0) {  
    out.write(buf, 0, n); 
}
out.flush();  
out.close();

除了许多其他变体之外，它们似乎总是陷入while循环。我应该将响应作为字节读取，然后将字节数组转换为字符串。为什么这会陷入while循环？

Answer 1

我认为您的情况有误，应该是＆gt; 0而不是＆gt; = 0

Answer 2

您必须发送有关HTTP协议的正确数据。试试这个

    try {
        String hostname = "stackoverflow.com";
        String requestHeaders[][] = {
            { "Host" , hostname } ,
            { "User-Agent" , "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36" } ,

        };
        String pathname = "questions/33047629/basic-http-client-from-scratch/33047769#33047769";
        int port = 80;
        Socket socket = new Socket(hostname, port);
        InputStream inStream = socket.getInputStream();
        DataOutputStream outStream = new DataOutputStream(socket.getOutputStream());
        String data = "GET /"+pathname+" HTTP/1.1\r\n";
        for (int i=0;i<requestHeaders.length;i++){
            data += requestHeaders[0]+": "+requestHeaders[1]+"\r\n";
        }
        data += "\r\n";
        outStream.writeChars(data.getBytes());
        outStream.flush();
    }
    catch (Exception e) {
        System.out.println(e);
    }

有一些浏览器插件显示浏览器发送的标头。您可以从插件中学习它们并实现它们，因为我实现了2个标题

从头开始的基本HTTP客户端

2 个答案: