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Refactoring code and guicify it

As we have just released the first milestone of the Spring Data JPA project I'd like to give you a quick introduction into its features. As you probably know, the Spring framework provides support to build a JPA based data access layer. So what does Spring Data JPA add to this base support? To answer that question I'd like to start with the data access components for a sample domain implemented using plain JPA + Spring and point out areas that leave room for improvement. After we've done that I will refactor the implementations to use the Spring Data JPA features to address these problem areas. The sample project as well as a step by step guide of the refactoring steps can be found on Github.

JMock is a library that supports test-driven development1 of Java2 code with mock objects3. Mock objects help you design and test the interactions between the objects in your programs.

"JMock is a library that supports test-driven development of Java code with mock objects. Mock objects help you design and test the interactions between the objects in your programs. The jMock library: makes it quick and easy to define mock objects, so you don't break the rhythm of programming. lets you precisely specify the interactions between your objects, reducing the brittleness of your tests. works well with the autocompletion and refactoring features of your IDE plugs into your favourite test framework is easy to extend."

Database Change Management You never develop code without version control, why do you develop your database without it? Liquibase is an open source (Apache 2.0 Licensed), database-independent library for tracking, managing and applying database changes. It is built on a simple premise: All database changes are stored in a human readable yet trackable form and checked into source control. Liquibase Supports: Extensibility Merging changes from multiple developers Code branches Multiple Databases Managing production data as well as various test datasets Cluster-safe database upgrades Automated updates or generation of SQL scripts that can be approved and applied by a DBA Update rollbacks Database "diff"s Generating starting change logs from existing database

The JDT project provides the tool plug-ins that implement a Java IDE supporting the development of any Java application, including Eclipse plug-ins. It adds a Java project nature and Java perspective to the Eclipse Workbench as well as a number of views, editors, wizards, builders, and code merging and refactoring tools. The JDT project allows Eclipse to be a development environment for itself.

lambdaj is a library that makes easier to address this issue by allowing to manipulate collections in a pseudo-functional and statically typed way. In our experience to iterate over collection, especially in nested loops, is often error prone and makes the code less readable. The purpose of this library is to alleviate these problems employing some functional programming techniques but without losing the static typing of java. We impose this last constraint to make refactoring easier and safer and allow the compiler to do its job.

Querydsl is a framework which enables the construction of type-safe SQL-like queries for multiple backends including JPA, JDO and SQL in Java. Instead of writing queries as inline strings or externalizing them into XML files they are constructed via a fluent API. Code completion in IDE (all properties, methods and operations can be expanded in your favorite Java IDE) Almost no syntactically invalid queries allowed (type-safe on all levels) Domain types and properties can be referenced safely (no Strings involved!) Adopts better to refactoring changes in domain types Incremental query definition is easier Querydsl is licensed under the LGPL 2.1 license.

"EasyMock provides Mock Objects for interfaces (and objects through the class extension) by generating them on the fly using Java's proxy mechanism. Due to EasyMock's unique style of recording expectations, most refactorings will not affect the Mock Objects. So EasyMock is a perfect fit for Test-Driven Development. EasyMock is open source software available under the terms of the Apache 2.0 license. Development, downloads and issue tracking are hosted on SourceForge. "