I am at the stage now where I have a fairly good understanding of programming/development, using Java.

Could anyone tell me the best way for me to start using testing packages? I have looked at Hibernate but not surer where to go with it...

I use Eclipse 3.5 on Mac OS X. Is it a case of writing scripts to test methods? What 开发者_StackOverflow中文版is unit-testing? etc.

Where do I begin?

Many thanks. Alex

What is Unit Testing

Unit testing is writing code (i.e. test code) that passes known inputs into code under test and then validating the code under test returns expected outputs. It's the most granular testing you can perform on an application. To make it easier, usually a unit testing framework is used. For Java, JUnit is the most popular, but TestNG is also notable.

Getting Started

Unit testing frameworks provide tools for test execution, validation and results reporting. For your setup, Eclipse has built in support for JUnit. Eclipse is able to automatically detect tests, compile tests and code under test, execute tests, and report results within the IDE. Furthermore, failures are reported as clickable stack trace information that loads the corresponding file at the given line number.

Mock Objects

That you're also working with Hibernate, suggests you also investigate a mock object framework as well - such as jMock. Mock objects are usually substituted as part of a code under tests's composition and serve two purposes: (1) returning known outputs and (2) recording they've been called and how so that unit tests can introspect that information as part of validation.

The ability to use Mock objects to make testing easier is predicated on dependency injection. That is other entities that compose the object under test. The idea is decoupling dependencies (e.g. Hibernate) to focus on testing algorithms that manipulate that data you're working with.

Database

However, if you've got code that is not easily refactored, or perhaps you want to validate database code, you can also test Hibernate interaction as well. In that case you want a database in a known state. Three approaches come to mind:

Restoring a database backup at the beginning of each test execution.
Use dbunit, which provides its own mechanisms for maintain state.
Transactional locking with rollback. Wrap the entire case is wrapped with a try{} finally{}, where the latter always rolls back the transaction.

James Shore ("a thought leader in the Agile software development community") has a series of screen casts of him demonstrating Test Driven Development, using Eclipse.

http://jamesshore.com/Blog/Lets-Play/

While there are many ways to start testing, there is no "best" way so there's no point in looking for that as a starting point.

Search the web for a good tutorial on junit and do it. That will be the absolute best way to get started IMO. Don't get sidetracked with code coverage or integrating with Hudson or any of the other tasks that are on the periphery to testing. Focus on writing a handful (or 10) if tests first.

Once you understand the basics you can start looking at other tools to see if they meet your needs any better or worse than junit.

First up: Hibernate is not a testing package.

Now that's out of the way, I'd suggest you take a look at JUnit. Read up on unit testing first so you know what it is (the Wikipedia entry is a good place to start), then try the JUnit cookbook. Write some unit tests for a small piece of your code to see how it works, then move on to bigger chunks.

While you are at it, take a look at other development tools like Cobertura (for finding out how good your test coverage is) and static analysis tools like Findbugs and Checkstyle. These all integrate nicely with Ant and probably Eclipse, too.

If you are interested in improving your coding standards and build systems then I highly recommend using Ant, JUnit, Cobertura, Checkstyle and Findbugs together with a continuous integration server (e.g. Hudson or CruiseControl) and a version control system (e.g. git). With a toolkit like that you can't go wrong.

There are other frameworks out there (TestNG, Mockito etc) so take a look at them, too, and decide which you prefer (EDIT: And which work nicely together. Mockito + JUnit is a good combination.)