java.io.IOException : Server returned HTTP response code: 405 for URL 异常

Question

我有一个在线 servlet，我正在尝试联系它以进行一些基本测试。这是 servlet 代码:

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


public class index extends HttpServlet {
    private static final long serialVersionUID = 1L;

    public index() {
        super();
    }

    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        long time1 = System.currentTimeMillis();
        long time2 = time1 + 10000;
        out.println(time1);
        long i = 400000000l;
            while (System.currentTimeMillis() < time2) {
                i++;
            }
            out.print(time2);
    }
}

现在，我尝试使用以下代码从服务器获取信息:

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpRequest {
    public static void main(String args[]) {
        BufferedReader rd;
        OutputStreamWriter wr;

            try {
                URL url = new URL("http://blahblahblah/index");
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setDoOutput(true);
                wr = new OutputStreamWriter(conn.getOutputStream());
                wr.flush();

                conn.setConnectTimeout(50000);
                rd = new BufferedReader(
                new InputStreamReader(conn.getInputStream()));
                String line;
                while ((line = rd.readLine()) != null) {
                    System.out.println(line);
                }
             } catch (Exception e) {
                 System.out.println(e.toString());
               }

     }
}

但是我一直收到相同的 405 错误。我做错了什么？

Answer 1

您看到的是 HttpServlet 对 doPost() 的默认实现，因为您没有在 override 中索引 servlet。

protected void doPost(HttpServletRequest req, HttpServletResponse resp)
    throws ServletException, IOException
{
    String protocol = req.getProtocol();
    String msg = lStrings.getString("http.method_post_not_supported");
    if (protocol.endsWith("1.1")) {
        resp.sendError(HttpServletResponse.SC_METHOD_NOT_ALLOWED, msg);
    } else {
        resp.sendError(HttpServletResponse.SC_BAD_REQUEST, msg);
    }
}

立即发送 405 响应。

这是因为你打电话

conn.getOutputStream()

这使得 URLConnection 认为您默认发送的是 POST，而不是您期望的 GET。您甚至都没有使用 OutputStream 那么为什么要打开它，然后 flush() 然后再不使用它呢？

wr = new OutputStreamWriter(conn.getOutputStream());
wr.flush();