3614: AVRO-4223 Gradle plugin for generating Java code

lang/java/.gitignore

@@ -20,3 +20,6 @@
 dependency-reduced-pom.xml
 mapred/userlogs/
 tools/userlogs/
+gradle-plugin/build
+gradle-plugin/.kotlin
+gradle-plugin/.gradle

lang/java/gradle-plugin/README.md

@@ -0,0 +1,59 @@
+# Avro Gradle plugin (in development)
+
+Gradle plugin that generates Java code from Avro schemas
+
+## Usage
+
+### Add avro extension
+In `build.gradle.kts`:
+
+Add plugin
+
+```kotlin
+plugins {
+    id("eu.eventloopsoftware.avro-gradle-plugin") version "0.0.2"
+}
+```
+Add Avro dependency
+
+```kotlin
+implementation("org.apache.avro:avro:1.12.1")
+```
+Configure Avro Gradle plugin
+```kotlin
+avro {
+    sourceDirectory = "src/main/avro"
+    // All properties are available in `GradlePluginExtension.kt`
+} 
+```
+
+In `settings.gradle.kts`:
+
+Plugin is published on Maven Central:
+```kotlin
+pluginManagement {
+    repositories {
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
+```
+
+
+
+### Add a task hook
+For Intellij to recognize the newly generated Java files add this to `build.gradle.kts`:
+
+```kotlin
+tasks.named("compileKotlin") { dependsOn(tasks.named("avroGenerateJavaClasses")) }
+```
+
+### Generate Java classes
+
+`./gradlew avroGenerateJavaClasses`
+
+
+## Example project that uses avro-gradle-plugin
+https://codeberg.org/frevib/use-gradle-plugin-test
+
+

lang/java/gradle-plugin/build.gradle.kts

@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+plugins {
+    kotlin("jvm") version "2.2.10"
+    `java-gradle-plugin`
+    `maven-publish`
+}
+
+group = "org.apache.avro"
+version = "1.13.0-SNAPSHOT"
+
+repositories {
+    mavenCentral()
+    mavenLocal()
+}
+
+dependencies {
+    //implementation("org.gradle:gradle-tooling-api:7.1.1")
+    implementation("org.apache.avro:avro-compiler:${version}")
+    testImplementation(kotlin("test"))
+}
+
+tasks.test {
+    useJUnitPlatform()
+}
+kotlin {
+    jvmToolchain(17)
+}
+
+java {
+    withSourcesJar()
+}
+
+
+gradlePlugin {
+    plugins {
+        create("gradlePlugin") {
+            id = "org.apache.avro.avro-gradle-plugin"
+            implementationClass = "org.apache.avro.gradle.plugin.GradlePlugin"
+        }
+    }
+}

lang/java/gradle-plugin/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.14-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists