Java tips: Java sends a POST request to a web site

Sending a POST request to a web site only takes a few simple steps:

First, you need to talk to urlconnection under the URL. Urlconnection can be easily obtained from the URL. For example:

// Using java.net. url and

// Java.net. urlconnection

URL url = new

URL ("http://jobsearch.dice.com/jobsearch/jobsearch.cgi ");

Urlconnection connection = URL. openconnection ();

Set the connection to the output mode. Urlconnection is usually used as input, such as downloading a Web page. By setting urlconnection as output, you can transmit data to your web page. The following describes how to do this:

...

Connection. setdooutput (true );

Finally, to get the outputstream, put it in the writer and put it into the post information, for example:

...

Outputstreamwriter out = newoutputstreamwriter (UC. getoutputstream (), "8859_1 ");

Out. Write ("username = Bob & Password =" + password + "");

// Remember to clean up

Out. Flush ();

Out. Close ();

In this way, you can send a post that looks like this:

Post/Jobsearch. cgi HTTP 1.0

Accept: text/plain

Content-Type: Application/X-WWW-form-urlencoded

Content-Length: 99

Username = Bob

Password = someword

Once the message is sent successfully, use the following method to obtain the server response:

Connection. getinputstream ();

Some websites use post instead of get, because post can carry more data without URLs, which makes it look not so huge. Using the rough Code listed above, Java code can easily communicate with these sites.