From d6d3610d388b8500a152cf7f3c8bbccca6244b08 Mon Sep 17 00:00:00 2001
From: Andrey Manzharov <amanzharov@yandex.ru>
Date: Fri, 11 Aug 2023 07:33:30 +0300
Subject: [PATCH] Allow configuring persistent index format version in the
 Maven plugin

---
 maven-plugin/src/it/indexVersion/pom.xml      | 45 +++++++++++++++++++
 .../jandex/maven/indexVersion/SomeClass.java  |  4 ++
 .../src/it/indexVersion/verify.groovy         | 13 ++++++
 maven-plugin/src/it/smoketest/pom.xml         |  2 +-
 .../org/jboss/jandex/maven/JandexGoal.java    | 12 ++++-
 5 files changed, 74 insertions(+), 2 deletions(-)
 create mode 100644 maven-plugin/src/it/indexVersion/pom.xml
 create mode 100644 maven-plugin/src/it/indexVersion/src/main/java/org/jboss/jandex/maven/indexVersion/SomeClass.java
 create mode 100644 maven-plugin/src/it/indexVersion/verify.groovy

diff --git a/maven-plugin/src/it/indexVersion/pom.xml b/maven-plugin/src/it/indexVersion/pom.xml
new file mode 100644
index 00000000..98371f00
--- /dev/null
+++ b/maven-plugin/src/it/indexVersion/pom.xml
@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>org.jboss.jandex</groupId>
+  <artifactId>jandex-maven-plugin-indexVersion</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+  </properties>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>@version.maven-compiler-plugin@</version>
+      </plugin>
+
+      <plugin>
+        <groupId>@project.groupId@</groupId>
+        <artifactId>@project.artifactId@</artifactId>
+        <version>@project.version@</version>
+        <executions>
+          <execution>
+            <id>make-index</id>
+            <goals>
+              <goal>jandex</goal>
+            </goals>
+            <configuration>
+              <!-- oldest version of V2 index -->
+              <indexVersion>6</indexVersion>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+</project>
diff --git a/maven-plugin/src/it/indexVersion/src/main/java/org/jboss/jandex/maven/indexVersion/SomeClass.java b/maven-plugin/src/it/indexVersion/src/main/java/org/jboss/jandex/maven/indexVersion/SomeClass.java
new file mode 100644
index 00000000..58818f75
--- /dev/null
+++ b/maven-plugin/src/it/indexVersion/src/main/java/org/jboss/jandex/maven/indexVersion/SomeClass.java
@@ -0,0 +1,4 @@
+package org.jboss.jandex.maven.indexVersion;
+
+public class SomeClass {
+}
diff --git a/maven-plugin/src/it/indexVersion/verify.groovy b/maven-plugin/src/it/indexVersion/verify.groovy
new file mode 100644
index 00000000..8d4d7d9c
--- /dev/null
+++ b/maven-plugin/src/it/indexVersion/verify.groovy
@@ -0,0 +1,13 @@
+import org.jboss.jandex.IndexReader
+import org.jboss.jandex.PackedDataInputStream
+
+def jandexFile = new File(basedir, 'target/classes/META-INF/jandex.idx')
+assert jandexFile.exists() : "File ${jandexFile} does not exist"
+assert jandexFile.length() > 0 : "File ${jandexFile} is empty"
+
+def data = new PackedDataInputStream(jandexFile.newInputStream())
+assert data.readInt() == 0xBABE1F15 as int // magic
+assert data.readUnsignedByte() == 6 // version
+
+def index = new IndexReader(jandexFile.newInputStream()).read()
+assert index.getKnownClasses().size() == 1 : "Index ${jandexFile} does not contain exactly 1 class"
diff --git a/maven-plugin/src/it/smoketest/pom.xml b/maven-plugin/src/it/smoketest/pom.xml
index d0edf1c0..a227c6dc 100644
--- a/maven-plugin/src/it/smoketest/pom.xml
+++ b/maven-plugin/src/it/smoketest/pom.xml
@@ -42,4 +42,4 @@
       </plugin>
     </plugins>
   </build>
-</project>
\ No newline at end of file
+</project>
diff --git a/maven-plugin/src/main/java/org/jboss/jandex/maven/JandexGoal.java b/maven-plugin/src/main/java/org/jboss/jandex/maven/JandexGoal.java
index 2e8ae10a..8d61ef9c 100644
--- a/maven-plugin/src/main/java/org/jboss/jandex/maven/JandexGoal.java
+++ b/maven-plugin/src/main/java/org/jboss/jandex/maven/JandexGoal.java
@@ -113,6 +113,12 @@ public class JandexGoal extends AbstractMojo {
     @Parameter(defaultValue = "jandex.idx")
     private String indexName;
 
+    /**
+     * Persistent index format version to write. Defaults to max supported version.
+     */
+    @Parameter
+    private Integer indexVersion;
+
     /**
      * Skip execution if set.
      */
@@ -169,7 +175,11 @@ public void execute() throws MojoExecutionException {
             Files.createDirectories(indexDir.toPath());
             try (OutputStream out = new CachingOutputStream(indexFile)) {
                 IndexWriter writer = new IndexWriter(out);
-                writer.write(index);
+                if (indexVersion != null) {
+                    writer.write(index, indexVersion);
+                } else {
+                    writer.write(index);
+                }
             }
         } catch (IOException e) {
             throw new MojoExecutionException("Could not save index " + indexFile, e);