JAVA servlet中没有内容的放置/发布请求

Question

I want to send a PUT/POST request to another JAVA servlet informing that something has completed.I dont want to send any content. Say the URL is;

putURL = "http://"+recorderIp+":"+recorderPort +"/vodingest/rec/"+recId+"/completed"

I dont have any content(file content) to sent.The servlet once see this request in his PUT/POST methods , he will know that something has completed and does the needful.

How can I do this in JAVA servlet. Please help me.

Answer 1

we have many methods to POST request to another servlet.

1) Send Redirect

request.sendRedirect("myServletName.java")

2) LInk

out.println("<a href=\"http://localhost:8080/HelloWorld/myServlet\"> Hello World Servlet </a>");

3) Request Dispatcher

 request.getRequestDispatcher("/myServletName").forward(request, response);

and in request object you can pass values also to another servlet.

request.setParams("recId" , "completed")

I guess the third option is better for you. Hope that will solve your problem.

Answer 2

First, PUT is by default not enabled on web servers (including Tomcat), so before you try this, make sure that PUT is enabled or stick to POST. As mentioned above dispatching is possible if your two servlets (assuming there are 2 servlets) are under the same container. Otherwise if you are doing it from a stand alone client, the approach would be different. The below should work in all environments:

Use HttpURLConnection ( https://docs.oracle.com/javase/7/docs/api/java/net/HttpURLConnection.html ) Use setRequestMethod to POST Use doInput/doOutput if you need to write and read from the stream (in your case I don't think either is necessary).

This is relatively straight forward method and would work. If you need more flexibility of the client, you could use Apache Commons HTTP Client.

One point of note, if you have nothing to write and nothing really to read, why are you thinking of using PUT?