Algorithm description

Quick description

Quick sort is an algorithm to sort elements (we will use a vector)

In short, the procedure for sorting is done in this way: i take a vector's element (the pivot) (for example the first element of the vector) and then i move the pivot and all the elements, with value less than the value of pivot, at left of the pivot and all the elements, with value more hight, to the right of the pivot.

Summary

In this article i want to show
- an introduction to sax
- a simple use case that dimostrate the basic functionality of SAX
- how to validate an xml document with SAX
- how to use the filters

JAXB allow binding between java objects and xml instance.
Basically with JAXB you can do 'marshall' and 'unmarshall' operations.

Marshall means the process of conversion from java objects to xml instance. With unmarshall means the opposite.

Marshall example

To start with marshalling we need at least our domain class. Suppose we have a city with many person and i want to have an xml file with a root element city wich contains more element of kind people. To do that we need one object of type city wich contains a collection of person objects

Introduction

This pattern is also know as ’Observer’ (GoF). The mainly difference is that in architectural patterns there is a distinction for what is a components and what is a connectors. Here i want show just a basic working without this distinction. Besides i want show how implement it using the API of java, utility class that simplify the java implementation.

What is the problem

I have one or more objects (observer or listner or subscriber) that are interested to know when there are some events from another object (subject or publisher) and they want be informed when it happen. When that event happen the subscriber can perform their action that can be different from subscriber to subscriber.