Gain insights into configuring and utilizing JUnit 5 for Java unit testing. Learn about writing effective unit tests, integrating assertions, assumptions, parameterized tests, and their significance.

Junit 5 is the most popular and widely used Java unit testing framework. In this course, you will learn step by step, how to configure and use JUnit 5 testing framework. This course will teach you how to write unit tests with JUnit 5, covering topics like why unit tests are important, the structure of good unit tests, assertions, assumptions and parameterized tests and more.

Java Unit Testing with JUnit 5

# @DisabledIfSystemProperty and @EnabledIfSystemProperty ###

Junit 5 helps us to disable or enable test cases using various conditions. JUnit Jupiter API provides annotations in `org.junit.jupiter.api.condition` package to enable/disable tests based on a certain condition. The annotations provided by API can be applied to test methods as well as the class itself. 
The two annotations which use system properties and specified regex to disable or enable tests are - `@DisabledIfSystemProperty` and `@EnabledIfSystemProperty`. Let's take a look at a demo.

package com.hubberspot.junit5.disabled;

import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertTrue;

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.condition.DisabledIfSystemProperty;

public class DisabledIfSystemPropertyTest {
	
    @Test
    void testOnAllSystemProperties() {
        assertTrue(3 > 0);
    }
    
    @DisabledIfSystemProperty(named="user.name", matches="dinesh")
    @Test
    void testDisabledIfUserNameMatchesDinesh() {
    	assertFalse(0 > 4);
    }
    
    @DisabledIfSystemProperty(named="os.name", matches="Windows")
    @Test
    void testDisabledIfOperatingSystemMatchesWindows() {
    	assertFalse(10 > 40);
    }
}


DisabledIfSystemPropertyTest.java

Above test program has 3 test methods and  `@DisabledIfSystemProperty` is applied on 2 test methods as. 
1. `testDisabledIfUserNameMatchesDinesh()` - Here, `@DisabledIfSystemProperty` annotation takes in two attributes such as ***`named`*** and ***`matches`***. The value provided to ***`named`*** attribute is **`"user.name"`** and value provided to ***`matches`*** attribute is **`"dinesh"`**. It makes the test method skip to execute if System property by name `"user.name"` matches `"dinesh"`.
2. `testDisabledIfOperatingSystemMatchesWindows()` - Here, `@DisabledIfSystemProperty` annotation takes in two attributes such as ***`named`*** and ***`matches`***. The value provided to ***`named`*** attribute is **`"os.name"`** and value provided to ***`matches`*** attribute is **`"Windows"`**. It makes the test method skip to execute if System property by name `"os.name"` matches `"Windows"`.

The above test methods are executed on System properties as - 
1. **`user.name`** - **`dinesh`**
2. **`os.name`** - **`Mac OS X`** 

Thus, output shows that 1 test method marked as, `@DisabledIfSystemProperty(named="user.name", matches="dinesh")` is skipped for execution.
 

This lesson demonstrates how to disable or enable test methods or a complete test class using System property level conditions.

Getting Started

Assertions in Junit 5

Junit 5 Test Lifecycle Callbacks

Display Names

Dependency Injection for Constructors and Methods

Assumptions in Junit 5

Disable or Enable Tests in Junit 5

Nested Tests in Junit 5

JUnit 5 Integration with Maven

Parameterized Tests in Junit 5

Repeated Tests in Junit 5

Appendix

System Property Conditions - @DisabledIfSystemProperty and @EnabledIfSystemProperty

@DisabledIfSystemProperty and @EnabledIfSystemProperty