Question

I have the following code in Perl which posts to my HTTP Servlet, calling an API with some XML data.

my $my_hash = {
'env.adapterName' => "DefaultAdapter",
'env.systemName'  => "DefaultSystem",
'env.userId' => "admin",
'env.progId' => "PerlHttpTest",
InteropApiName => $apiName,
InteropApiData  => $xmlData
};

my $res = $ua->request(POST  'http://hostname/interop/InteropHttpServlet', $my_hash);

I would like to do this in Java but I am struggling. Could someone please point me in the right direction? I want to post data to my servlet as above and get the response back (it will be XML).

Answer 1

The standard Java SE API offers you the java.net.URLConnection to fire and handle HTTP requests.

String query = "env.adapterName=DefaultAdapter"
    + "&env.systemName=DefaultSystem"
    + "&env.userId=admin"
    + "&env.progId=PerlHttpTest";
    + "&" + URLEncoder.encode(interopApiName, "UTF-8") + "=" + URLEncoder.encode(apiName, "UTF-8")
    + "&" + URLEncoder.encode(interopApiData, "UTF-8") + "=" + URLEncoder.encode(xmlData, "UTF-8");

URLConnection connection = new URL("http://hostname/interop/InteropHttpServlet").openConnection();
connection.setDoOutput(true); // Triggers POST.
connection.getOutputStream().write(query.getBytes("UTF-8"));

InputStream response = connection.getInputStream();
// ...

There exist 3rd party API’s which makes this all little easier, like Apache HttpComponents Client.

See also:

• Using java.net.URLConnection to fire and handle HTTP requests