Add github action for releasing to maven central repository

Author: purejava

.github/workflows/build.yml renamed to .github/workflows/build_and_release.yml

@@ -1,4 +1,4 @@
-name: Java CI with Maven
+name: Build and deploy releases to GitHub
 
 on:
   push:
@@ -34,7 +34,7 @@ jobs:
     steps:
       - name: Checkout code
         uses: actions/checkout@v2
-      - name: Create Release
+      - name: Create GitHub Release
         id: create_release
         uses: actions/create-release@v1
         env:

.github/workflows/release_to_maven.yml

@@ -0,0 +1,27 @@
+name: Release to Maven central repository
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out Git repository
+        uses: actions/checkout@v2
+
+      - name: Install Java and Maven
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+
+      - name: Release Maven package
+        uses: samuelmeuli/action-maven-publish@v1
+        with:
+          maven_args: -D=skipTests=true
+          gpg_private_key: ${{ secrets.GPG_PRIVATE_KEY }}
+          gpg_passphrase: ${{ secrets.GPG_PASSPHRASE }}
+          nexus_username: ${{ secrets.NEXUS_USERNAME }}
+          nexus_password: ${{ secrets.NEXUS_PASSWORD }}