gradle: Integrate spotless to format Java and Kotlin code

See https://github.com/diffplug/spotless.

Signed-off-by: utzcoz <utzcoz@outlook.com>

build.gradle

@@ -52,6 +52,9 @@ plugins {
 
     // So we don't have to check in generated files: we start with SVGs for vector art.
     id "com.quittle.svg-2-android-vector" version "0.0.6" apply false
+
+    // Spotless for Java and Kotlin's code formatting
+    id 'com.diffplug.spotless' version "6.18.0" apply false
 }
 
 ext {

src/xrt/auxiliary/android/build.gradle

@@ -5,6 +5,7 @@ plugins {
     id 'com.android.library'
     id 'kotlin-android'
     id 'dagger.hilt.android.plugin'
+    id 'com.diffplug.spotless'
 }
 
 android {
@@ -49,3 +50,19 @@ dependencies {
     // Only a Java file has annotations right now, so we don't yet need kapt
     annotationProcessor "com.google.dagger:hilt-compiler:$hiltVersion"
 }
+
+spotless {
+    java {
+        target 'src/main/java/**/*.java'
+        // apply a specific flavor of google-java-format.
+        googleJavaFormat('1.8').aosp().reflowLongStrings()
+        // fix formatting of type annotations.
+        formatAnnotations()
+    }
+
+    kotlin {
+        target 'src/main/java/**/*.kt'
+        // Use ktfmt(https://github.com/facebook/ktfmt) as the default Kotlin formatter.
+        ktfmt('0.43').kotlinlangStyle()
+    }
+}

src/xrt/ipc/android/build.gradle

@@ -7,6 +7,8 @@ plugins {
 
     id 'kotlin-kapt'
     id 'dagger.hilt.android.plugin'
+
+    id 'com.diffplug.spotless'
 }
 
 android {
@@ -64,3 +66,19 @@ dependencies {
     api "com.google.dagger:hilt-android:$hiltVersion"
     kapt "com.google.dagger:hilt-compiler:$hiltVersion"
 }
+
+spotless {
+    java {
+        target 'src/main/java/**/*.java'
+        // apply a specific flavor of google-java-format.
+        googleJavaFormat('1.8').aosp().reflowLongStrings()
+        // fix formatting of type annotations.
+        formatAnnotations()
+    }
+
+    kotlin {
+        target 'src/main/java/**/*.kt'
+        // Use ktfmt(https://github.com/facebook/ktfmt) as the default Kotlin formatter.
+        ktfmt('0.43').kotlinlangStyle()
+    }
+}

src/xrt/targets/android_common/build.gradle

@@ -11,8 +11,26 @@ plugins {
 
     // SVG files in the "raw" resource directory will be transformed into vector drawables of the same name.
     id 'com.quittle.svg-2-android-vector'
+
+    // Use spotless to format Java and Kotlin code.
+    id 'com.diffplug.spotless'
 }
 
+spotless {
+    java {
+        target 'src/main/java/**/*.java'
+        // apply a specific flavor of google-java-format.
+        googleJavaFormat('1.8').aosp().reflowLongStrings()
+        // fix formatting of type annotations.
+        formatAnnotations()
+    }
+
+    kotlin {
+        target 'src/main/java/**/*.kt'
+        // Use ktfmt(https://github.com/facebook/ktfmt) as the default Kotlin formatter. .
+        ktfmt('0.43').kotlinlangStyle()
+    }
+}
 
 android {
     compileSdk project.sharedCompileSdk

src/xrt/targets/openxr_android/build.gradle

@@ -17,6 +17,25 @@ plugins {
 
     // SVG files in the "raw" resource directory will be transformed into vector drawables of the same name.
     id 'com.quittle.svg-2-android-vector'
+
+    // Use spotless to format Java and Kotlin code
+    id 'com.diffplug.spotless'
+}
+
+spotless {
+    java {
+        target 'src/main/java/**/*.java'
+        // apply a specific flavor of google-java-format.
+        googleJavaFormat('1.8').aosp().reflowLongStrings()
+        // fix formatting of type annotations.
+        formatAnnotations()
+    }
+
+    kotlin {
+        target 'src/main/java/**/*.kt'
+        // Use ktfmt(https://github.com/facebook/ktfmt) as the default Kotlin formatter.
+        ktfmt('0.43').kotlinlangStyle()
+    }
 }
 
 // apply from: file("../android_common/fetch-eigen.gradle")