如何将数据从一个Web应用程序发送到另一个

Question

我在两个不同的服务器上有两个Web应用程序。我想在标头或请求中向其他Web应用程序发送一些数据，我该怎么做，请帮帮我。

Answer 1

You can pass data by many means:

1. by making http request from your app:

    URLConnection conn = new URL("your other web app servlet url").openConnection(); // pass data using conn. Then on other side you can have a servlet that will receive these calls. 

2. By using JMS for asynchronous communication.

3. By using webservice (SOAP or REST)

4. By using RMI

5. By sharing database between the apps. So one writes to a table and the other reads from that table

6. By sharing file system file(s)...one writes to a file the other reads from a file.

7. You can use socket connection.

Answer 2

HttpClient can help

http://hc.apache.org/index.html

Apache HttpComponents

The Apache HttpComponents™ project is responsible for creating and maintaining a toolset of low level Java components focused on HTTP and associated protocols.

Answer 3

One web application is functioning as the client of the other. You can use the org.apache.http library to create your HTTP client code in Java. How you will do this depends on a couple of things:

1. Are you using http or https?
2. Does the application you are sending data to have a REST API?
3. Do you have a SOAP based web service?

If you have a SOAP based web service, then creating a Java client for it is very easy. If not, you could do something like this and test the code in a regular Java client before trying to run it in the web application.

 import org.apache.http.client.utils.*;
 import org.apache.http.*; 
 import org.apache.http.impl.client.*;

  HttpClient httpclient = new DefaultHttpClient();
  try {
     URIBuilder builder = new URIBuilder();
     builder.setHost("yoursite.com").setPath(/appath/rsc/);
     builder.addParameter("user", username);
     builder.addParameter("param1", "SomeData-sentAsParameter");
     URI uri = builder.build();
     HttpGet httpget = new HttpGet(uri);
     HttpResponse response = httpclient.execute(httpget);
     System.out.println(response.getStatusLine().toString());
     if (response.getStatusLine().getStatusCode() == 200) {
        String responseText = EntityUtils.toString(response.getEntity());
        httpclient.getConnectionManager().shutdown();
     } else {
        log(Level.SEVERE, "Server returned HTTP code "
                + response.getStatusLine().getStatusCode());
     }
  } catch (java.net.URISyntaxException bad) {
     System.out.println("URI construction error: " + bad.toString());
  }