On my current project, we are using Alfresco and working on an integration with JBoss Portal. In this case we were building a component that allowed for the browsing, uploading, moving, renaming, and deleting of files. We had built all the Alfresco Web Scripts to support these operations. In order to ensure the proper auditing of the changes, we needed to implement a WebScripts component that performed impersonation of the user that was executing the action. After some Google searching, we found the following common solution to the problem:

public String impersonate(String username) {
String currentUser = AuthenticationUtil.getCurrentUserName();

I recently had an occasion where I had to perform an HTTP POST with JSON data from a Java service class as oppose to Javascript. No amount of Google searches turned up the answer I was after. Here are the steps I took to do so:

STEP 1 - Handle HTTP Post
The project I am working we were already using Commons HTTPClient which has a PostMethod class that peforms an HTTP Post. Here is the code to setup the post:

HttpClient clientService = new HttpClient();
PostMethod post = new PostMethod();