java

In the past few years many techniques have been developed to help applications interact with each other. One of them are webservice-interfaces. These interfaces are extremly popular in the world of Java software development. One Framework that can be used to build such interfaces is Apache CXF. Apache CXF delivers a toolset to develop interfaces using different protocols like XML/HTTP, RESTful HTTP, Corba and SOAP. In this article i'd like to show how easy it could be to develop a simple SOAP-webservice based on Apache CXF 2.2.6 and the Spring Framework 3.0.1. You can download the full example at the bottom of this article.

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Since a few days Spring 3.0 is out. The frameworks core APIs (e.g. the BeanFactory) have been updated for Java 1.5. But there are also some new features in Spring 3.0. Today I will take a look on Springs new OXM-feature and see how it can be used. Naturally all features added to the Spring framework are easy to use. Let's see if Springs simplicity still exists...

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Escaping is the art of transforming a text into a transport format from which it can be extracted again without any modification.

That's something every developer does - to a certain level. For example take the sentence

Matthias says: "I love Javascript".

Now put this sentence in a Java source code:

If you don't complain about this, your compiler will. In Java (any many other programming languages) the quotation mark " has a special meaning, it defines a string. So if you have a string containing the quotation mark, you need to escape it:

If you print out s, the original text is shown:

Recently I read about a nice article in one of my monthly magazines. I won't give you the author right now, otherwise googling for the solution would be too easy.
He stated it as a possible interview question, but I really like it for the algorithm side of it. It reminded my strongly of some of the
examples given in the book How Would You Move Mount Fuji? Which is excellent by the way.

So your task is to write a Java function which computes the following:Read more

When I first had to use regular expressions in Java I made some fairly common mistakes.
Let's start out with a simple search.

simple string matching

We want to search the string: asdfdfdasdfdfdf for occurences of dfd. I can find it four times in the String.
Let's evaluate what our little Java program says.

The result should be 2. So either our code is wrong, or the logic works differently than expected. And indeed, it does.Read more

Today we're going on with the third part of our Maven 2 tutorial series. Because of the comment of Enrico I decided that this article will focus on how to configure eclipse for the usage of Maven 2 projects and how to generate the eclipse-specific files by using Maven 2. I will show these things by using the example project of part 1 and part 2 of our Maven 2 tutorial series.

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Welcome back to the second part of our tutorial-series on Maven 2. This part will focus on the pom.xml and the Maven 2 dependency management, Maven properties and dependency scopes. To get started let's first set up a project similar to the project we used in the first part of this tutorial. Set up the project as described in the article Maven 2 (Part 1): Setting up a simple Apache Maven 2 Project and reopen the pom.xml.

Dependencies

Some dependencies often are needed to write your applications. Commonly we (developers, developers, developers,...) are using some open source libraries and frameworks (e.g. the spring application framework or apache commons-logging,...). Sometimes own libraries should be referenced by a java project. To solve this problem Maven delivers a very good dependency mechanism that manages the dependencies of your project transitivly.

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Hibernate is a well known object-relational mapping library (ORM) for Java. It allows you to map entries in your relational database to objects in your Java classes.
Usually this is done by a mapping file written in XML. As this approach is a bit more expensive we will use annotations to map a class to the relating database table.
Based on the Maven tutorial by my colleague Phillip, we will begin with a quickstart archetype and include Hibernate and a MySQL connection. Then we will write a simple data access object (DAO) which maps to the database table we will create. After that we use a class to set up the connection and fill the database with some of our objects.

Note: This is just a superficial glance at Hibernate to get in touch with the framework.
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The Google App Engine (GAE) is a wonderful playground for your apps, especially when you have no server at hand. It gives you everything you need for free, up to a certain limit. As I happened to be a Java developer it became really interesting when the GAE started supporting Java. You have to register for a GAE account and then apply for Java to be activated. There is a small waiting time but there still seem to be open slots.

As I'm working with Apache Wicket at the moment I thought it would be a nice idea to give you everything you need to get started with development with the GAE and Wicket as your frontend. So in the following lines we will set up a minimal Java / Wicket application and deploy it into the GAE.Read more

Java software development is often associated with repetitive tasks like building project's java classes, generating documentation and reporting. Doing this repetitive tasks manually costs a lot of time and tend to be error-prone. In addition to that it is extremely boring to do the same tasks again and again. These tasks should get automated, because they are often equal. To automate these tasks a build tool that could do this work is needed. Today, many java projects are using the Maven as a build tool to manage these objectives. The Maven project reached big popularity by making repetitive tasks automatable.

Another advantage when using Maven is that all dependencies referenced by the project are resolved automatically. This is extremely helpful for bigger java projects that use a huge set of dependencies. To explain how to use Maven and to help you to get into it we start a new tutorial-series about Maven 2 at united-coders.com. The initial part of this tutorial describes how to set up a Maven 2 project structure. Further parts of this tutorial-series will describe the main functionality of Maven (e.g. plugins, archetypes, the dependency mechanism, profiles, repositories, scopes...) stepwise.

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