Use GitHub actions for build and release

.github/workflows/build.yml

@@ -0,0 +1,32 @@
+name: Build
+
+on:
+  push:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/cache@v2
+        with:
+          path: |
+            ~/.gradle/loom-cache
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+          restore-keys: |
+            gradle-
+
+      - uses: actions/checkout@v2
+      - name: Set up JDK
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+
+      - name: Build with Gradle
+        run: ./gradlew build

.github/workflows/release.yml

@@ -0,0 +1,43 @@
+name: Release
+
+on:
+  release:
+    types:
+      - published
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/cache@v2
+        with:
+          path: |
+            ~/.gradle/loom-cache
+            ~/.gradle/caches
+            ~/.gradle/wrapper
+          key: gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+          restore-keys: |
+            gradle-
+
+      - uses: actions/checkout@v2
+      - name: Set up JDK
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+
+      - name: Grant execute permission for gradlew
+        run: chmod +x gradlew
+
+      - name: Build and publish with Gradle
+        run: ./gradlew build publish
+        env:
+          MAVEN_URL: ${{ secrets.MAVEN_URL }}
+          MAVEN_USERNAME: ${{ secrets.MAVEN_USERNAME }}
+          MAVEN_PASSWORD: ${{ secrets.MAVEN_PASSWORD }}
+
+      - name: Upload GitHub release
+        uses: AButler/upload-release-assets@v2.0
+        with:
+          files: 'build/libs/*.jar'
+          repo-token: ${{ secrets.GITHUB_TOKEN }}

build.gradle

@@ -3,6 +3,8 @@ plugins {
   id 'maven-publish'
 }
 
+def env = System.getenv()
+
 sourceCompatibility = JavaVersion.VERSION_1_8
 targetCompatibility = JavaVersion.VERSION_1_8
 
@@ -69,13 +71,13 @@ publishing {
   }
 
   repositories {
-    if (project.hasProperty("mavenUrl")) {
+    if (env.MAVEN_URL) {
       maven {
         credentials {
-          username project.mavenUsername ?: ""
-          password project.mavenPassword ?: ""
+          username env.MAVEN_USERNAME
+          password env.MAVEN_PASSWORD
         }
-        url project.mavenUrl ?: ""
+        url env.MAVEN_URL
       }
     } else {
       mavenLocal()