Blog Archives
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01: JUnit with Mockito step by step

Step 1: Create a simple maven project say “code-quality”

Step 2: Import into eclipse.

#1. Validator code & unit testing

Step 3: Validator interface & implementation

Step 4: Write a unit test to test the “”.

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01: jvisualvm tutorial to sample Java heap memory

Java does not have a sizeof operator like C++ does. Java uses automatic memory management known as the Garbage Collection, hence it is not that important to evaluate size of various objects. But, for the purpose of learning & fixing any potential memory issues, I have used “jvisualvm”,

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02: jvisualvm to detect memory leak – a quick tutorial style Java demo

This is a companion post to 8 Java Memory Management Interview Q&A demonstrating a memory leak scenario step by step with jvisualvm, which is a free profiling tool that gets shipped with JDK. Step 1: Code that causes memory leak Here is a sample code that causes memory leak. …...

02: Unit testing with JUnit, Mockito & Spring

Step 1: Create a simple Maven project from a command-line. Just press enter for all the prompts.

Step 2: Import the above “simple-mocking-test” in the file system into eclipse. File –> Import –> “Existing Maven Projects” and then select the “simple-mocking-test”

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03: Mockito to fully mock the DAO layer

This extends Part 1: Unit testing with JUnit, Mockito & Spring by mocking the DAO layer with the Mockito framework. Step 1: Service and DAO layer interfaces and implementations Service Layer DAO Layer This layer will be mocked by Mockito in the next step. … Read more ›...

04: Mockito partially mocking with @Spy

This extends Part 2: Mockito to fully mock the DAO layer by modifying the service layer to demonstrate partial mocking with “Mockito.spy”. In the “SimpleServiceImpl” we are interested in only testing the method “processUser(int id)” and want to mock the method “getUserById(int id)” by always returning “Sam”. So, … Read...

05: Mockito & PowerMock partially mocking private methods with @Spy

This extends Part 3: Mockito partially mocking with @Spy by making the method “processUser(int id)” as a private method. Mockito framework cannot mock “private” methods, hence the “PowerMock” framework is added to the pom.xml file Step 1: Add “PowerMock” … Read more ›...

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