Use protobuf-maven-plugin

- No need to manually setup protoc as a pre-requisite
- More portable

.github/workflows/deploy_to_central.yaml

@@ -9,10 +9,6 @@ jobs:
       - name: Install gpg secret key
         run: |
           cat <(echo -e "${{ secrets.OSSRH_GPG_SECRET_KEY }}") | gpg --batch --import
-      - name: Install Protoc
-        uses: arduino/setup-protoc@v1
-        with:
-          version: "3.x"
       - name: Checkout
         uses: actions/checkout@v2
       - name: Set up Maven Central Repository

.github/workflows/java_ci.yml

@@ -13,10 +13,6 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - name: Install Protoc
-        uses: arduino/setup-protoc@v1
-        with:
-          version: "3.x"
       - name: Checkout
         uses: actions/checkout@v2
       - name: Set up JDK 11

pom.xml

@@ -25,7 +25,9 @@
         <maven-compiler-plugin.version>3.10.0</maven-compiler-plugin.version>
 
         <!-- dependencies -->
-        <protobuf-java.version>3.25.0</protobuf-java.version>
+        <protobuf.version>3.25.0</protobuf.version>
+        <protobuf-maven-plugin.version>0.6.1</protobuf-maven-plugin.version>
+        <os-maven-plugin.version>1.7.1</os-maven-plugin.version>
         <net.i2p.crypto.eddsa.version>0.3.0</net.i2p.crypto.eddsa.version>
         <vavr.version>0.10.3</vavr.version>
         <re2j.version>1.6</re2j.version>
@@ -109,6 +111,32 @@
     </profiles>
 
     <build>
+        <extensions>
+            <extension>
+                <groupId>kr.motd.maven</groupId>
+                <artifactId>os-maven-plugin</artifactId>
+                <version>${os-maven-plugin.version}</version>
+            </extension>
+        </extensions>
+        <pluginManagement>
+            <plugins>
+                <plugin>
+                    <groupId>org.xolstice.maven.plugins</groupId>
+                    <artifactId>protobuf-maven-plugin</artifactId>
+                    <version>${protobuf-maven-plugin.version}</version>
+                    <executions>
+                        <execution>
+                            <goals>
+                                <goal>compile</goal>
+                            </goals>
+                        </execution>
+                    </executions>
+                    <configuration>
+                        <protocArtifact>com.google.protobuf:protoc:${protobuf.version}:exe:${os.detected.classifier}</protocArtifact>
+                    </configuration>
+                </plugin>
+            </plugins>
+        </pluginManagement>
         <plugins>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
@@ -162,49 +190,8 @@
                 </configuration>
             </plugin>
             <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-antrun-plugin</artifactId>
-                <version>${maven-antrun.version}</version>
-                <executions>
-                    <execution>
-                        <id>exec-protoc</id>
-                        <phase>generate-sources</phase>
-                        <configuration>
-                            <target>
-                                <mkdir dir="${project.build.directory}/generated-sources"/>
-                                <exec executable="protoc" failonerror="true">
-                                    <arg value="-I"/>
-                                    <arg value="${project.basedir}"/>
-                                    <arg value="--java_out"/>
-                                    <arg value="${project.build.directory}/generated-sources"/>
-                                    <arg line="schema.proto"/>
-                                </exec>
-                            </target>
-                        </configuration>
-                        <goals>
-                            <goal>run</goal>
-                        </goals>
-                    </execution>
-                </executions>
-            </plugin>
-            <plugin>
-                <groupId>org.codehaus.mojo</groupId>
-                <artifactId>build-helper-maven-plugin</artifactId>
-                <version>${build-helper-maven.version}</version>
-                <executions>
-                    <execution>
-                        <id>add-classes</id>
-                        <phase>generate-sources</phase>
-                        <goals>
-                            <goal>add-source</goal>
-                        </goals>
-                        <configuration>
-                            <sources>
-                                <source>${project.build.directory}/generated-sources</source>
-                            </sources>
-                        </configuration>
-                    </execution>
-                </executions>
+                <groupId>org.xolstice.maven.plugins</groupId>
+                <artifactId>protobuf-maven-plugin</artifactId>
             </plugin>
             <plugin>
                 <artifactId>maven-surefire-plugin</artifactId>
@@ -222,7 +209,7 @@
         <dependency>
             <groupId>com.google.protobuf</groupId>
             <artifactId>protobuf-java</artifactId>
-            <version>${protobuf-java.version}</version>
+            <version>${protobuf.version}</version>
         </dependency>
         <dependency>
             <groupId>net.i2p.crypto</groupId>