From 17f2df6f6e2ee453668e4cd8a562a93434d531d8 Mon Sep 17 00:00:00 2001
From: Himanshu Kandwal <hkandwal@linkedin.com>
Date: Wed, 5 Jun 2024 09:50:17 -0700
Subject: [PATCH] [apache/helix] -- Enable JDK 1.8 (backward) compatibility for
 dependent modules of meta-client and helix-core (#2806)

We would like to provide a backward compatible support to our consumers where they also have an option to use JDK-8 compiled meta-client jar, if they have such a requirement. By default we will generate JDK-11 jars and JDK-8 jars using a classifier. In this PR, we are enabling the JDK* build of full sub-tree of the helix-core and meta-client modules. This includes:
helix-common, zookeeper-api, metadata-store-directory-common, metrics-common
---
 helix-common/pom.xml                          | 48 +++++++++++++++++++
 .../helix/constants/InstanceConstants.java    |  8 ++--
 metadata-store-directory-common/pom.xml       | 48 +++++++++++++++++++
 metrics-common/pom.xml                        | 48 +++++++++++++++++++
 zookeeper-api/pom.xml                         | 48 +++++++++++++++++++
 5 files changed, 197 insertions(+), 3 deletions(-)

diff --git a/helix-common/pom.xml b/helix-common/pom.xml
index 40f64043b6..82e35c86dd 100644
--- a/helix-common/pom.xml
+++ b/helix-common/pom.xml
@@ -89,6 +89,54 @@
       </resource>
     </resources>
     <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.12.1</version>
+        <executions>
+          <execution>
+            <id>JDK 8</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <outputDirectory>${project.build.outputDirectory}_jdk8</outputDirectory>
+              <release>8</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+          <execution>
+            <id>JDK 11</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <release>11</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.3.0</version>
+        <executions>
+          <execution>
+            <id>default-package-jdk11</id>
+            <phase>package</phase>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+            <configuration>
+              <classesDirectory>${project.build.outputDirectory}_jdk8</classesDirectory>
+              <classifier>jdk8</classifier>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-assembly-plugin</artifactId>
diff --git a/helix-common/src/main/java/org/apache/helix/constants/InstanceConstants.java b/helix-common/src/main/java/org/apache/helix/constants/InstanceConstants.java
index 07eb4989d3..85c22c460b 100644
--- a/helix-common/src/main/java/org/apache/helix/constants/InstanceConstants.java
+++ b/helix-common/src/main/java/org/apache/helix/constants/InstanceConstants.java
@@ -2,6 +2,8 @@
 
 import java.util.Set;
 
+import com.google.common.collect.ImmutableSet;
+
 public class InstanceConstants {
   public static final String INSTANCE_NOT_DISABLED = "INSTANCE_NOT_DISABLED";
 
@@ -9,7 +11,7 @@ public class InstanceConstants {
    * The set contains the InstanceOperations that are allowed to be assigned replicas by the rebalancer.
    */
   public static final Set<InstanceOperation> ASSIGNABLE_INSTANCE_OPERATIONS =
-      Set.of(InstanceOperation.ENABLE, InstanceOperation.DISABLE);
+      ImmutableSet.of(InstanceOperation.ENABLE, InstanceOperation.DISABLE);
 
 
   /**
@@ -18,14 +20,14 @@ public class InstanceConstants {
    * TODO: Remove this when the deprecated HELIX_ENABLED is removed.
    */
   public static final Set<InstanceOperation> INSTANCE_DISABLED_OVERRIDABLE_OPERATIONS =
-      Set.of(InstanceOperation.ENABLE, InstanceOperation.DISABLE, InstanceOperation.EVACUATE);
+      ImmutableSet.of(InstanceOperation.ENABLE, InstanceOperation.DISABLE, InstanceOperation.EVACUATE);
 
 
   /**
    * The set of InstanceOperations that are not allowed to be populated in the RoutingTableProvider.
    */
   public static final Set<InstanceOperation> UNSERVABLE_INSTANCE_OPERATIONS =
-      Set.of(InstanceOperation.SWAP_IN, InstanceOperation.UNKNOWN);
+      ImmutableSet.of(InstanceOperation.SWAP_IN, InstanceOperation.UNKNOWN);
 
   public enum InstanceDisabledType {
     CLOUD_EVENT,
diff --git a/metadata-store-directory-common/pom.xml b/metadata-store-directory-common/pom.xml
index f173397cc4..98e2e5cb03 100644
--- a/metadata-store-directory-common/pom.xml
+++ b/metadata-store-directory-common/pom.xml
@@ -113,6 +113,54 @@
       </resource>
     </resources>
     <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.12.1</version>
+        <executions>
+          <execution>
+            <id>JDK 8</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <outputDirectory>${project.build.outputDirectory}_jdk8</outputDirectory>
+              <release>8</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+          <execution>
+            <id>JDK 11</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <release>11</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.3.0</version>
+        <executions>
+          <execution>
+            <id>default-package-jdk11</id>
+            <phase>package</phase>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+            <configuration>
+              <classesDirectory>${project.build.outputDirectory}_jdk8</classesDirectory>
+              <classifier>jdk8</classifier>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-assembly-plugin</artifactId>
diff --git a/metrics-common/pom.xml b/metrics-common/pom.xml
index 2dbe016cb2..433c575aac 100644
--- a/metrics-common/pom.xml
+++ b/metrics-common/pom.xml
@@ -84,6 +84,54 @@
       </resource>
     </resources>
     <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.12.1</version>
+        <executions>
+          <execution>
+            <id>JDK 8</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <outputDirectory>${project.build.outputDirectory}_jdk8</outputDirectory>
+              <release>8</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+          <execution>
+            <id>JDK 11</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <release>11</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.3.0</version>
+        <executions>
+          <execution>
+            <id>default-package-jdk11</id>
+            <phase>package</phase>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+            <configuration>
+              <classesDirectory>${project.build.outputDirectory}_jdk8</classesDirectory>
+              <classifier>jdk8</classifier>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-assembly-plugin</artifactId>
diff --git a/zookeeper-api/pom.xml b/zookeeper-api/pom.xml
index d44160fdb7..bfb993feec 100644
--- a/zookeeper-api/pom.xml
+++ b/zookeeper-api/pom.xml
@@ -133,6 +133,54 @@
       </resource>
     </resources>
     <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.12.1</version>
+        <executions>
+          <execution>
+            <id>JDK 8</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <outputDirectory>${project.build.outputDirectory}_jdk8</outputDirectory>
+              <release>8</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+          <execution>
+            <id>JDK 11</id>
+            <phase>compile</phase>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+            <configuration>
+              <release>11</release>
+              <fork>true</fork>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.3.0</version>
+        <executions>
+          <execution>
+            <id>default-package-jdk11</id>
+            <phase>package</phase>
+            <goals>
+              <goal>jar</goal>
+            </goals>
+            <configuration>
+              <classesDirectory>${project.build.outputDirectory}_jdk8</classesDirectory>
+              <classifier>jdk8</classifier>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-assembly-plugin</artifactId>