Reference Queues

In the previous posts we had a look at weak and soft references. The java.lang.ref package also includes a class ReferenceQueue. As per the class documentation:

Reference queues, to which registered reference objects are appended by the garbage 
collector after the appropriate reachability changes are detected.

Soft References in Java

In the last post I looked at using weak references in my java code. As we saw Java has not just strong and weak but also soft and phantom references.
Firstly, what are soft references ?

Weak References in Java

I have been looking at the java.lang.ref package with a view to understanding references in java. It all started when I tried to understand WeakHashMap and its use in string pools. The various related terms mentioned totally flummoxed me and made some additional study essential. Below is a summary of my attempts at understanding.
Java objects in the memory are classified as:

Views in ModelAndView

We had an interesting scenario in our code. It all started out when we had this complex controller that included methods specific to a certain flow. In case of any exception, we used an error handler to redirect the flow to an error page. The code would be along the lines of