Explore Spotless for Java projects

[tschaffter]

We have been using Google formatting configuration since the time we added the first Java project. In #712, I updated our formatting setup to use google-java-format.

The author of @nxrocks/nx-spring-boot recommend to use Spotless. We generate our Java projects with this generator and they come configured to use Spotless to format Java files. The default configuration runs google-java-format under the hood.

Most of the features of Spotless are available when using Gradle, which we now use. :)

Tasks:

• Generate a new Java library with @nxrocks/nx-spring-boot and review the Spotless setup.
• Review Spotless + Gradle setup (see instructions)
• Enable integration of Spotless + Gradle with VS Code

Depends on:

• Add google-java-format formatter #712

Note
The Spotless plugin for Gradle was actually added in #713 to the user service.

[tschaffter]

Early exploration

• build.gradle

  plugins {
    id 'java'
    id 'com.diffplug.spotless' version '6.8.0'
  }
  
  repositories {
    mavenCentral()
    mavenLocal()
  }
  
  spotless {
    // format 'misc', {
    //   target '*.gradle', '*.md', '.gitignore'
  
    //   trimTrailingWhitespace()
    //   indentWithSpaces(2)
    //   endWithNewline()
    // }
  
    java {
      target 'src/*/java/**/*.java'
  
      importOrder()
      removeUnusedImports()
      googleJavaFormat()
    }
  }

• The VS Code extension richardwillis.vscode-spotless-gradle should interface with the Spotless + Gradle setup.

  • Recommended configuration in settings.json is:

      "[java]": {
        // "files.trimTrailingWhitespace": false,
        "spotlessGradle.diagnostics.enable": true,
        "spotlessGradle.format.enable": true,
        "editor.defaultFormatter": "richardwillis.vscode-spotless-gradle",
        "editor.codeActionsOnSave": {
          "source.fixAll.spotlessGradle": true
        }
      },

[tschaffter]

VS Code extension Spotless Gradle

• Its activation requires gradlew in the workspace folder.
• Requires build.gradle in the workspace folder.