Category Archives: Software development practices

Immutable objects

Posted on April 15, 2018 by Robert Piasecki

Most of the objects in Java are mutable. It means that their state/fields can be changed after the object was created. The examples of those are: ArrayList, Calendar, StringBuilder. Immutable objects An object is immutable if its state/fields cannot be … Continue reading →

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Parameterized unit tests in JUnit

Posted on April 11, 2014 by Robert Piasecki

Sometimes you may want to execute a series of tests which differ only by input values and expected results. Instead of writing each test separately, it is much better to abstract the actual tests into a single class and provide … Continue reading →

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Common exception misuses in Java (and not only)

Posted on March 22, 2014 by Robert Piasecki

Exceptions were introduced in many programming languages as a standard method to report and handle errors. If you have ever used functions that return special values (usually -1 or NULL) to indicate an error, you should know how easy it is … Continue reading →

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Definition of Done: or why it is very risky to say that something is done

Posted on February 10, 2014 by Robert Piasecki

General meaning of word done may seem obvious to everybody but once you start thinking about this, it becomes clear that done may have different meanings depending on the situation and personal point of view. In this article I would … Continue reading →

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Using JUnit, JaCoCo and Maven for code coverage

Posted on February 1, 2014 by Robert Piasecki

JaCoCo is quite a new tool for measuring and reporting code coverage with full support for Java 7. Currently it supports instruction, branch, line, method and class coverage which is pretty anything you can expect from this kind of tool. … Continue reading →

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Assertions in Java

Posted on January 14, 2014 by Robert Piasecki

One of the rules of defensive programming is to detect the errors as soon as they appear. The main idea behind this is that we can get precise information about the location of the error and the event which caused … Continue reading →

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Assertions on Android

Posted on January 14, 2014 by Robert Piasecki

If you program in Java on Android, you know that Android has its own virtual machine called DalvikVM which is not compatible with JVM from Oracle. In fact, the difference is so big that you cannot run plain Java application … Continue reading →

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Test driven development

Posted on January 12, 2014 by Robert Piasecki

Test driven development is an important and valued part of agile practices. In test driven  development (in short TDD) developers first write tests for new functionality (e.g. a class) and later they implement it. The order is crucial and I … Continue reading →

Posted in Java, Software development practices | Tagged , , , , | 2 Comments