怎么解决doPost不能单独使用的问题，而doGet就可以单独使用 import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class HttpServletTest extends HttpServlet { @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp)   throws ServletException, IOException {  System.out.println("查看"); }}