Say I have a DAO method like this:

public Collection getBlogs() throws Exception {
Session session = sesFac.openSession();
List blogs = session.find("from Blog");
session.close();
return blogs;
}

1. How do I get this to be cached, so that this only executes a DB query the first time the method is executed?

2. If I can get the getBlogs method to loads all the blogs from the DB into a cache, how can I create another method that gets a specific blog from the cache?

3. Let's say I have another method that updates the blog with id = 5. Is there a way for me to invalidate/reload just the blog with id = 5? If not, how do invalidate the whole cache?

Did you read the rest of the documentation, esp. the chapter about caching and performance?

I assume you are talking about Chapter 14? I couldn't figure out how any of the caches their relate to this example. Session Cache just caches data within a session, right? I need to cache the data in one session and then get that data from another. Does the 2nd level or the query cache do that for me?

Yes.