Home » Java » Core Java » Test Driven Traps, part 2

About Jakub Nabrdalik

Jakub Nabrdalik
Jakub is a software developer: programmer, architect, analyst, team leader, project manager and coach at TouK. Infected with eXtreme Programming and Software Craftsmanship. Test driving and pair programming web and enterprise applications since 2005 in several languages.

Test Driven Traps, part 2

The Story of a Unit in Unit Tests

In the previous part of this article, you could see some bad, though popular, test samples. But I’m not a professional critic (also known as a troll, or a hater), to grumble about without having anything constructive to say. Years of TDD have taught me more than just how bad the things can go. There are many simple but effective tricks, that can make you test-life much easier.

Imagine this: you have a booking system for a small conference room in a small company. By some strange reason, it has to deal with off-line booking. People post their booking requests to some frontend, and once a week you get a text file with working hours of the company, and all the bookings (for what day, for how long, by whom, submitted at what point it time) in random order. Your system should produce a calendar for the room, according to some business rules (first come, first served, only in office business hours, that sort of things).

As part of the analysis, we have a clearly defined input data, and expected outcomes, with examples. Beautiful case for TDD, really. Something that sadly never happens in the real life.

Our sample test data looks like this:

class TestData {
    static final String INPUT_FIRST_LINE = '0900 1730\n';
    static final String FIRST_BOOKING    = '2011-03-17 10:17:06 EMP001\n' +
                                           '2011-03-21 09:00 2\n';
    static final String SECOND_BOOKING   = '2011-03-16 12:34:56 EMP002\n' +
                                           '2011-03-21 09:00 2\n';
    static final String THIRD_BOOKING    = '2011-03-16 09:28:23 EMP003\n' +
                                           '2011-03-22 14:00 2\n';
    static final String FOURTH_BOOKING   = '2011-03-17 10:17:06 EMP004\n' +
                                           '2011-03-22 16:00 1\n';
    static final String FIFTH_BOOKING    = '2011-03-15 17:29:12 EMP005\n' +
                                           '2011-03-21 16:00 3';

    static final String INPUT_BOOKING_LINES =
                                            FIRST_BOOKING +
                                            SECOND_BOOKING +
                                            THIRD_BOOKING +
                                            FOURTH_BOOKING +
                                            FIFTH_BOOKING;

    static final String CORRECT_INPUT = INPUT_FIRST_LINE + INPUT_BOOKING_LINES;

    static final String CORRECT_OUTPUT = '2011-03-21\n' +
                                         '09:00 11:00 EMP002\n' +
                                         '2011-03-22\n' +
                                         '14:00 16:00 EMP003\n' +
                                         '16:00 17:00 EMP004\n' +
                                         '';
}

So now we start with a positive test:

BookingCalendarGenerator bookingCalendarGenerator =  new BookingCalendarGenerator();

@Test
public void shouldPrepareBookingCalendar() {
    //when
    String calendar = bookingCalendarGenerator.generate(TestData.CORRECT_INPUT);

    //then
    assertEquals(TestData.CORRECT_OUTPUT, calendar);
}

It looks like we have designed a BookingCalendarGenerator with a “generate” method. Fair enough. Lets add some more tests. Tests for the business rules. We get something like this:

    @Test
    public void noPartOfMeetingMayFallOutsideOfficeHours() {
        //given
        String tooEarlyBooking = '2011-03-16 12:34:56 EMP002\n' +
                                 '2011-03-21 06:00 2\n';

        String tooLateBooking = '2011-03-16 12:34:56 EMP002\n' +
                                '2011-03-21 20:00 2\n';

        //when
        String calendar = bookingCalendarGenerator.generate(TestData.INPUT_FIRST_LINE + tooEarlyBooking + tooLateBooking);

        //then
        assertTrue(calendar.isEmpty());
    }

    @Test
    public void meetingsMayNotOverlap() {
        //given
        String firstMeeting = '2011-03-10 12:34:56 EMP002\n' +
                              '2011-03-21 16:00 1\n';

        String secondMeeting = '2011-03-16 12:34:56 EMP002\n' +
                               '2011-03-21 15:00 2\n';

        //when
        String calendar = bookingCalendarGenerator.generate(TestData.INPUT_FIRST_LINE + firstMeeting + secondMeeting);

        //then
        assertEquals('2011-03-21\n' +
                     '16:00 17:00 EMP002\n', calendar);
    }

    @Test
    public void bookingsMustBeProcessedInSubmitOrder() {
        //given
        String firstMeeting = '2011-03-17 12:34:56 EMP002\n' +
                              '2011-03-21 16:00 1\n';

        String secondMeeting = '2011-03-16 12:34:56 EMP002\n' +
                               '2011-03-21 15:00 2\n';

        //when
        String calendar = bookingCalendarGenerator.generate(TestData.INPUT_FIRST_LINE + firstMeeting + secondMeeting);

        //then
        assertEquals('2011-03-21\n15:00 17:00 EMP002\n', calendar);
    }

    @Test
    public void orderingOfBookingSubmissionShouldNotAffectOutcome() {
        //given
        List<String> shuffledBookings = newArrayList(TestData.FIRST_BOOKING, TestData.SECOND_BOOKING,
                TestData.THIRD_BOOKING, TestData.FOURTH_BOOKING, TestData.FIFTH_BOOKING);
        shuffle(shuffledBookings);
        String inputBookingLines = Joiner.on('\n').join(shuffledBookings);

        //when
        String calendar = bookingCalendarGenerator.generate(TestData.INPUT_FIRST_LINE + inputBookingLines);

        //then
        assertEquals(TestData.CORRECT_OUTPUT, calendar);
    }   

That’s pretty much all. But what if we get some rubbish as the input. Or if we get an empty string? Let’s design for that:

    @Test(expected = IllegalArgumentException.class)
    public void rubbishInputDataShouldEndWithException() {
        //when
        String calendar = bookingCalendarGenerator.generate('rubbish');

        //then exception is thrown
    }

    @Test(expected = IllegalArgumentException.class)
    public void emptyInputDataShouldEndWithException() {
        //when
        String calendar = bookingCalendarGenerator.generate('');

        //then exception is thrown
    }

IllegalArgumentException is fair enough. We don’t need to handle it in any more fancy way. We are done for now. Let’s finally write the class under the test: BookingCalendarGenerator.

And so we do. And it comes out, that the whole thing is a little big for a single method. So we use the power of Extract Method pattern. We group code fragments into different methods. We group methods and data those operate on, into classes. We use the power of Object Oriented programming, we use Single Responsibility Principle, we use composition (or decomposition, to be precise) and we end up with a package like this:

We have one public class, and several package-scope classes. Those package scope classes clearly belong to the public one. Here’s a class diagram for clarity:

Those aren’t stupid data-objects. Those are full fledged classes. With behaviour, responsibility, encapsulation. And here’s a thing that may come to our Test Driven minds: we have no tests for those classes. We have only for the public class. That’s bad, right? Having no tests must be bad. Very bad. Right?

Wrong.

We do have tests. We fire up our code coverage tool and we see: 100% methods and classes. 95% lines. Not bad (I’ll get to that 5% of uncertainty in the next post).

But we have only a single unit test class. Is that good?

Well, let me put some emphasis, to point the answer out:

It’s a UNIT test. It’s called a UNIT test for a reason!

The unit does not have to be a single class. The unit does not have to be a single package. The unit is up to you to decide. It’s a general name, because your sanity, your common sense, should tell you where to stop.

So we have six classes as a unit, what’s the big deal? How about if somebody wants to use one of those classes, apart from the rest. He would have no tests for it, right?

Wrong. Those classes are package-scope, apart from the one that’s actually called in the test. This package-scope thing tells you: “Back off. Don’t touch me, I belong to this package. Don’t try to use me separately, I was design to be here!”.

So yeah, if a programmer takes one of those out, or makes it public, he would probably know, that all the guarantees are voided. Write your own tests, man.

How about if somebody wants to add some behaviour to one of those classes, I’ve been asked. How would he know he’s not breaking something?

Well, he would start with a test, right? It’s TDD, right? If you have a change of requirements, you code this change as a test, and then, and only then, you start messing with the code. So you are safe and secure.

I see people writing test-per-class blindly, without giving any thought to it, and it makes me cry. I do a lot of pair-programming lately, and you know what I’ve found? Java programmers in general do not use package-scope. Java programmers in general do not know, that protected means: for me, all my descendants, and EVERYONE in the same package. That’s right, protected is more than package-scope, not less a single bit. So if Java programmers do not know what a package-scope really is, and that’s, contrary to Groovy, is the default, how could they understand what a Unit is?

How high can I get?

Now here’s an interesting thought: if we can have a single test for a package, we could have a single test for a package tree. You know, something like this:

We all know that packages in Java are not really tree-like, that the only thing those have with the directory structure is by a very old convention, and we know that the directory structure is there only to solve the collision-of-names problem, but nevertheless, we tend to use packages, like if the name.after.the.dot had some meaning. Like if we could hide one package inside another. Or build layers of lasagne with them.

So is it O.K. to have a single test class for a tree of packages?

Yes it is.

But if so, where is the end to that? Can we go all the way up in the package tree, to the entry point of our application? Those… those would be integration tests, or functional tests, perhaps. Could we do that? Would that be good?

The answer is: it would. In a perfect world, it would be just fine. In our shitty, hanging-on-the-edge-of-a-knife, world, it would be insane. Why? Because functional, end-to-end test are slow. So slow. So horribly slow, that it makes you wanna throw them away and go some place where you would not have to be always waiting for something. A place of total creativity, constant feedback, and lightning fast safety.

And you’re back to unit testing.

There are even some more reasons. One being, that it’s hard to test all flows of the application, testing it end-to-end. You should probably do that for all the major flows, but what about errors, bad connections, all those tricky logic parts that may throw up at one point or another. No, sometimes it would be just too hard, to set up the environment for integration test like that, so you end up testing it with unit tests anyway.

The second reason is, that though functional tests do not pour concrete over your code, do not inhibit your creativity by repeating you algorithm in the test case, they also give no safety for refactoring. When you had a package with a single public class, it was quite obvious what someone can safely do, and what he cannot. When you have something enclosed in a library, or a plugin, it’s still obvious. But if you have thousands of public classes, and you are implementing a new feature, you are probably going to use some of them, and you would like to know that they are fine.

So, no, in our world, it doesn’t make sense to go with functional tests only. Sorry. But it also doesn’t make sense to create a test per class. It’s called the UNIT test, for a reason. Use that.

Happy coding and don’t forget to share!

Reference: Test Driven Traps, part 2 from our JCG partner Jakub Nabrdalik at the Solid Craft blog.

Do you want to know how to develop your skillset to become a Java Rockstar?
Subscribe to our newsletter to start Rocking right now!
To get you started we give you our best selling eBooks for FREE!
1. JPA Mini Book
2. JVM Troubleshooting Guide
3. JUnit Tutorial for Unit Testing
4. Java Annotations Tutorial
5. Java Interview Questions
6. Spring Interview Questions
7. Android UI Design
and many more ....
Email address:

Leave a Reply

Be the First to Comment!

avatar
  Subscribe  
Notify of
Want to take your Java skills to the next level?
Grab our programming books for FREE!
Here are some of the eBooks you will get:
  • Spring Interview QnA
  • Multithreading & Concurrency QnA
  • JPA Minibook
  • JVM Troubleshooting Guide
  • Advanced Java
  • Java Interview QnA
  • Java Design Patterns
The Spring Framework Cookbook
  • Learn the best practices of the Spring Framework
  • Build simple, portable, fast and flexible JVM-based systems and applications
  • Explore specific projects like Boot and Batch
The Spring Data Programming Cookbook
  • Learn how to use data access technologies and cloud-based data services
  • Set up the environment and create a basic project
  • Learn how to handle the various modules (e.g. JPA, MongoDB, Redis etc.)
The Selenium Programming Cookbook
  • Kick-start your own projects using this testing framework for web applications
  • Learn JUnit integration and Standalone Server functionality
  • Find out the most popular Interview Questions about the Selenium Framework
The Mockito Programming Cookbook
  • Kick-start your own web projects using this open source testing framework
  • Write simple test cases using the Mockito Framework
  • Learn how to integrate with JUnit, Maven and other frameworks
The JUnit Programming Cookbook
  • Learn basic usage and configuration of JUnit
  • Create multithreaded tests
  • Learn how to integrate with other testing frameworks
The JSF 2.0 Programming Cookbook
  • Build component-based user interfaces for web applications
  • Set up the environment and create a basic project
  • Learn Internationalization and Facelets Templates
The Amazon S3 Tutorial
  • Develop your own Amazon S3 based applications
  • Learn API usage and pricing
  • Get your own projects up and running in minimum time
Java Design Patterns
  • Learn how Design Patterns are implemented and utilized in Java
  • Understand the reasons why patterns are so important
  • Learn when and how to apply each one of them
Java Concurrency Essentials
  • Dive into the magic of concurrency
  • Learn about concepts like atomicity, synchronization and thread safety
  • Learn about testing concurrent applications
The IntelliJ IDEA Handbook
  • Kick-start your own programming projects using IntelliJ IDEA
  • Learn how to setup and install plugins
  • Create UIs with this Java integrated development environment
The Git Tutorial
  • Learn why Git differs from other version control systems
  • Explore Git's usage and best practises
  • Learn branching strategies
The Eclipse IDE Handbook
  • Explore the most widely used Java IDE
  • Learn how to setup and install plugins
  • Built your own projects up and running in minimum time
The Docker Containerization Cookbook
  • Explore the world’s leading software containerization platform
  • Learn how to wrap a piece of software in a complete filesystem
  • Learn how to use DNS and various commands
Developing Modern Applications With Scala
  • Develop modern Scala applications
  • Build SBT and reactive applications
  • Learn about testing and database access
The Apache Tomcat Cookbook
  • Explore Apache Tomcat open-source web server
  • Learn about installation, configuration, logging and clustering
  • Kick-start your own web projects using Apache Tomcat
The Apache Maven Cookbook
  • Explore the Apache Maven build automation tool
  • Learn about Maven's project structure and configuration
  • Learn about Maven's dependency management and plug-ins
The Apache Hadoop Cookbook
  • Explore the Apache Hadoop open-source software framework
  • Learn distributed caching and streaming
  • Kick-start your own web projects using Apache Hadoop
The Android Programming Cookbook
  • Explore the Android mobile operating system
  • Learn about services and page views
  • Learn about Google Maps and Bluetooth functionality
The Elasticsearch Tutorial
  • Explore the Elasticsearch search engine
  • Develop your own Elasticsearch based applications
  • Learn operations, Java API Integration and reporting
Amazon DynamoDB Tutorial
  • Develop your own Amazon DynamoDB based applications
  • Learn DynamoDB Concepts and Best Practices
  • Get your own projects up and running in minimum time
Java NIO Programming Cookbook
  • Learn features for intensive I/O operations
  • Follow a series of tutorials on Java NIO examples
  • Get knowledge on Java Nio Socket and Asynchronous Channels
JBoss Drools Cookbook
  • Explore Drools business rule management system
  • Follow a series of tutorials on Drools examples
  • Get knowledge on business rules for a shopping domain model
Vaadin Programming Cookbook
  • Explore Vaadin web framework for rich Internet applications
  • Learn the Architecture and Best Practices
  • Get knowledge on Data Binding and Custom Components
Groovy Programming Cookbook
  • Explore Apache Groovy object-oriented programming language
  • Create sample applications and explore interview questions
  • Get knowledge on Callback functionality and various widgets
GWT Programming Cookbook
  • Explore the open source Google Web Toolkit
  • Create sample applications and explore interview questions
  • Create and maintain complex JavaScript front-end applications in Java
Do you want to know how to develop your skillset to become a Java Rockstar?
Subscribe to our newsletter to start Rocking right now!
To get you started we give you our best selling eBooks for FREE!
1. JPA Mini Book
2. JVM Troubleshooting Guide
3. JUnit Tutorial for Unit Testing
4. Java Annotations Tutorial
5. Java Interview Questions
and many more ....
Email address:
Do you want to know how to develop your skillset to become a Java Rockstar?
Subscribe to our newsletter to start Rocking right now!
To get you started we give you our best selling eBooks for FREE!
1. JPA Mini Book
2. JVM Troubleshooting Guide
3. JUnit Tutorial for Unit Testing
4. Java Annotations Tutorial
5. Java Interview Questions
and many more ....
Email address:
Do you want to know how to develop your skillset to become a Java Rockstar?
Subscribe to our newsletter to start Rocking right now!
To get you started we give you our best selling eBooks for FREE!
1. JPA Mini Book
2. JVM Troubleshooting Guide
3. JUnit Tutorial for Unit Testing
4. Java Annotations Tutorial
5. Java Interview Questions
6. Spring Interview Questions
7. Android UI Design
and many more ....
Email address:
Want to be a DynamoDB Master ?
Subscribe to our newsletter and download the Amazon DynamoDB Tutorial right now!
In order to help you master this Amazon NoSQL database service, we have compiled a kick-ass guide with all the major DynamoDB features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Programming Interview Coming Up?
Subscribe to our newsletter and download the Ultimate Multithreading and Concurrency interview questions and answers collection right now!
In order to get you prepared for your next Programming Interview, we have compiled a huge list of relevant Questions and their respective Answers. Besides studying them online you may download the eBook in PDF format!
Email address:
Java Interview Coming Up?
Subscribe to our newsletter and download the Ultimate Spring interview questions and answers collection right now!
In order to get you prepared for your next Java Interview, we have compiled a huge list of relevant Questions and their respective Answers. Besides studying them online you may download the eBook in PDF format!
Email address:
Java Interview Coming Up?
Subscribe to our newsletter and download the Ultimate Java interview questions and answers collection right now!
In order to get you prepared for your next Java Interview, we have compiled a huge list of relevant Questions and their respective Answers. Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Java NIO Master ?
Subscribe to our newsletter and download the Java NIO Programming Cookbook right now!
In order to help you master Java NIO Library, we have compiled a kick-ass guide with all the major Java NIO features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Drools Master ?
Subscribe to our newsletter and download the JBoss Drools Cookbook right now!
In order to help you master Drools Business Rule Management System, we have compiled a kick-ass guide with all the major Drools features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be an iText Master ?
Subscribe to our newsletter and download the iText Tutorial right now!
In order to help you master iText Library, we have compiled a kick-ass guide with all the major iText features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be an Elasticsearch Master ?
Subscribe to our newsletter and download the Elasticsearch Tutorial right now!
In order to help you master Elasticsearch search engine, we have compiled a kick-ass guide with all the major Elasticsearch features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Scala Master ?
Subscribe to our newsletter and download the Scala Cookbook right now!
In order to help you master Scala, we have compiled a kick-ass guide with all the basic concepts! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JUnit Master ?
Subscribe to our newsletter and download the JUnit Programming Cookbook right now!
In order to help you master unit testing with JUnit, we have compiled a kick-ass guide with all the major JUnit features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Amazon Web Services ?
Subscribe to our newsletter and download the Amazon S3 Tutorial right now!
In order to help you master the leading Web Services platform, we have compiled a kick-ass guide with all its major features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Spring Framework ?
Subscribe to our newsletter and download the Spring Framework Cookbook right now!
In order to help you master the leading and innovative Java framework, we have compiled a kick-ass guide with all its major features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Eclipse IDE ?
Subscribe to our newsletter and download the Eclipse IDE Handbook right now!
In order to help you master Eclipse, we have compiled a kick-ass guide with all the basic features of the popular IDE! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master IntelliJ IDEA ?
Subscribe to our newsletter and download the IntelliJ IDEA Handbook right now!
In order to help you master IntelliJ IDEA, we have compiled a kick-ass guide with all the basic features of the popular IDE! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Docker ?
Subscribe to our newsletter and download the Docker Containerization Cookbook right now!
In order to help you master Docker, we have compiled a kick-ass guide with all the basic concepts of the Docker container system! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to create a kick-ass Android App ?
Subscribe to our newsletter and download the Android Programming Cookbook right now!
With this book, you will delve into the fundamentals of Android programming. You will understand user input, views and layouts. Furthermore, you will learn how to communicate over Bluetooth and also leverage Google Maps into your application!
Email address:
Want to be a GIT Master ?
Subscribe to our newsletter and download the GIT Tutorial eBook right now!
In order to help you master GIT, we have compiled a kick-ass guide with all the basic concepts of the GIT version control system! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Hadoop Master ?
Subscribe to our newsletter and download the Apache Hadoop Cookbook right now!
In order to help you master Apache Hadoop, we have compiled a kick-ass guide with all the basic concepts of a Hadoop cluster! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Spring Data ?
Subscribe to our newsletter and download the Spring Data Ultimate Guide right now!
In order to help you master Spring Data, we have compiled a kick-ass guide with all the major features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to create a kick-ass Android App ?
Subscribe to our newsletter and download the Android UI Design mini-book right now!
With this book, you will delve into the fundamentals of Android UI design. You will understand user input, views and layouts, as well as adapters and fragments. Furthermore, you will learn how to add multimedia to an app and also leverage themes and styles!
Email address:
Want to be a Java 8 Ninja ?
Subscribe to our newsletter and download the Java 8 Features Ultimate Guide right now!
In order to get you up to speed with the major Java 8 release, we have compiled a kick-ass guide with all the new features and goodies! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Java Annotations ?
Subscribe to our newsletter and download the Java Annotations Ultimate Guide right now!
In order to help you master the topic of Annotations, we have compiled a kick-ass guide with all the major features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JUnit Master ?
Subscribe to our newsletter and download the JUnit Ultimate Guide right now!
In order to help you master unit testing with JUnit, we have compiled a kick-ass guide with all the major JUnit features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Java Abstraction ?
Subscribe to our newsletter and download the Abstraction in Java Ultimate Guide right now!
In order to help you master the topic of Abstraction, we have compiled a kick-ass guide with all the major features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to master Java Reflection ?
Subscribe to our newsletter and download the Java Reflection Ultimate Guide right now!
In order to help you master the topic of Reflection, we have compiled a kick-ass guide with all the major features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JMeter Master ?
Subscribe to our newsletter and download the JMeter Ultimate Guide right now!
In order to help you master load testing with JMeter, we have compiled a kick-ass guide with all the major JMeter features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Servlets Master ?
Subscribe to our newsletter and download the Java Servlet Ultimate Guide right now!
In order to help you master programming with Java Servlets, we have compiled a kick-ass guide with all the major servlet API uses and showcases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JAXB Master ?
Subscribe to our newsletter and download the JAXB Ultimate Guide right now!
In order to help you master XML Binding with JAXB, we have compiled a kick-ass guide with all the major JAXB features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JDBC Master ?
Subscribe to our newsletter and download the JDBC Ultimate Guide right now!
In order to help you master database programming with JDBC, we have compiled a kick-ass guide with all the major JDBC features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JPA Master ?
Subscribe to our newsletter and download the JPA Ultimate Guide right now!
In order to help you master programming with JPA, we have compiled a kick-ass guide with all the major JPA features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Hibernate Master ?
Subscribe to our newsletter and download the Hibernate Ultimate Guide right now!
In order to help you master JPA and database programming with Hibernate, we have compiled a kick-ass guide with all the major Hibernate features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a JSF Master ?
Subscribe to our newsletter and download the JSF 2.0 Programming Cookbook right now!
In order to get you prepared for your JSF development needs, we have compiled numerous recipes to help you kick-start your projects. Besides reading them online you may download the eBook in PDF format!
Email address:
Want to be a Java Master ?
Subscribe to our newsletter and download the Advanced Java Guide right now!
In order to help you master the Java programming language, we have compiled a kick-ass guide with all the must-know advanced Java features! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Java Master ?
Subscribe to our newsletter and download the Java Design Patterns right now!
In order to help you master the Java programming language, we have compiled a kick-ass guide with all the must-know Design Patterns for Java! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be a Hadoop Master ?
Subscribe to our newsletter and download the Hadoop Tutorial right now!
In order to help you master Apache Hadoop, we have compiled a kick-ass guide with all the basic concepts of a Hadoop cluster! Besides studying them online you may download the eBook in PDF format!
Email address:
Want to be an Elastic Beanstalk Master ?
Subscribe to our newsletter and download the Amazon Elastic Beanstalk Tutorial right now!
In order to help you master AWS Elastic Beanstalk, we have compiled a kick-ass guide with all the major Elastic Beanstalk features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Amazon Elastic Beanstalk Tutorial
  • Develop your own Amazon Elastic Beanstalk based applications
  • Learn Java Integration and Command Line Interfacing
  • Get your own projects up and running in minimum time
Want to take your Java skills to the next level?
Grab our programming books for FREE!
Here are some of the eBooks you will get:
  • Spring Interview QnA
  • Multithreading & Concurrency QnA
  • JPA Minibook
  • JVM Troubleshooting Guide
  • Advanced Java
  • Java Interview QnA
  • Java Design Patterns
Insiders are already enjoying weekly updates and complimentary whitepapers!
Join them now to gain exclusive access to the latest news in the Java world, as well as insights about Android, Scala, Groovy and other related technologies.
Email address:
Want to be an ActiveMQ Master ?
Subscribe to our newsletter and download the Apache ActiveMQ Cookbook right now!
In order to help you master Apache ActiveMQ JMS, we have compiled a kick-ass guide with all the major ActiveMQ features and use cases! Besides studying them online you may download the eBook in PDF format!
Email address:
Apache ActiveMQ Cookbook
  • Explore Apache ActiveMQ Best Practices
  • Learn ActiveMQ Load Balancing and File Transfer
  • Develop your own Apache ActiveMQ projects