Database servlet

[Kaiser Lautern]

Hi all,

I'm trying to understand the DatabaseServlet from the MailReader example, but couldn't figure out exactly at what time has the hashtable been populated:

private synchronized void load() throws Exception {
 
// Initialize our database
database = new Hashtable();
 
// Acquire an input stream to our database file
if (debug >= 1)
    log("Loading database from '" + pathname + "'");
        InputStream is = getServletContext().getResourceAsStream(pathname);
        if (is == null) {
            log("No such resource available - loading empty database");
            return;
        }
BufferedInputStream bis = new BufferedInputStream(is);
 
// Construct a digester to use for parsing
Digester digester = new Digester();
digester.push(this);
digester.setDebug(debug);
digester.setValidating(false);
digester.addObjectCreate("database/user",
 "org.apache.struts.webapp.example.User");
digester.addSetProperties("database/user");
digester.addSetNext("database/user", "addUser");
digester.addObjectCreate("database/user/subscription",
 "org.apache.struts.webapp.example.Subscription");
digester.addSetProperties("database/user/subscription");
digester.addSetTop("database/user/subscription", "setUser");
 
// Parse the input stream to initialize our database
digester.parse(bis);
bis.close();

I don't know the Digester API, but it seems that all it does is to populate the User and Subscription DTO's. Next, in the init() method (where load() was called) it assumes already that the hashtable is populated:

try {
load();
getServletContext().setAttribute(Constants.DATABASE_KEY,
database);
}

Thanks,


Kaiser