[JAVA] A memo that enabled VS Code + JUnit 5 to be used on Windows 10

It was necessary to prepare the environment for the subject, so I made a note of it until it started working. I'm not very familiar with this area, so there may be some deficiencies, but I hope it helps.

Download OpenJDK

There are several types of JDK, but here we will use OpenJDK. https://openjdk.java.net/ As of October 2020, the latest was JDK15, so download this for Windows. Download for Windows, unzip it, and place the "jdk-15" that appears in any folder.

Java Extension Pack installation

Install the Java Extension Pack from the VS Code extension. After installation, display the settings with Ctrl +,, search for "Java: Home", click "Edit with settings.json", and specify the folder of "jdk-15" placed above. At this time, it is necessary to overlap two backslashes as follows.

"java.home": "C:\\hoge\\hoge\\jdk-15"

Creating a Java project

• Select "Java: Create Java Project ..." with Ctrl + Shift + P
• Select Maven in "Select the project type"
• Select "maven-archetype-quick start" in "Select an archetype ..."
• Select 1.4 in "Select a version ..."

When I select a folder and try to create a Java project, I get an error that the environment variable JAVA_HOME is not set.

Error: JAVA_HOME not found in your environment. 
Please set the JAVA_HOME variable in your environment to match the
location of your Java installation.

Start PowerShell with administrator privileges and set the Java storage path in the system environment variable JAVA_HOME with the following command. [System.Environment]::SetEnvironmentVariable("JAVA_HOME", "C:\hoge\hoge\jdk-15", "Machine") Then restart VS Code. (The above error was not resolved without rebooting.)

Generate a Java project again and set various IDs.

Define value for property 'groupId': (Specify what you want to be the package name)
Define value for property 'artifactId': (Specify what you want to be the jar name)
Define value for property 'version' 1.0-SNAPSHOT: : (Leave the default value without entering)
Define value for property 'package' (What you entered in groupId): : (Leave the default value without entering)

Open the generated Java project folder with VS Code, and the project creation is complete.

Run build

In the Explorer pane of VS Code, right-click App.java under the src folder and execute "Run" to build it, and "Hello World!" Is output to the terminal.

Change from JUnit 4 to 5

If you created a Java project as it is, JUnit4 was used, so change it to JUnit5. Since there is a sample project of JUnit5, change the pom.xml of the created project by referring to the pom.xml. https://raw.githubusercontent.com/junit-team/junit5-samples/r5.7.0/junit5-jupiter-starter-maven/pom.xml

This time I changed it like this.

+  <dependencyManagement>
+    <dependencies>
+      <dependency>
+        <groupId>org.junit</groupId>
+        <artifactId>junit-bom</artifactId>
+        <version>5.7.0</version>
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
+    </dependencies>
+  </dependencyManagement>
+
   <dependencies>
     <dependency>
-      <groupId>junit</groupId>
-      <artifactId>junit</artifactId>
-      <version>4.11</version>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
       <scope>test</scope>
     </dependency>
   </dependencies>

When you save pom.xml, a dialog asking if you want to synchronize is displayed. Click "Now" to synchronize. You can now use JUnit 5.