From e2f74f0a64030006ffb0f20d3a99006e04f4f704 Mon Sep 17 00:00:00 2001
From: Andrea Cavalli <andrea@cavallium.it>
Date: Fri, 22 Oct 2021 23:05:30 +0200
Subject: [PATCH] Support java modules

---
 scripts/core/build_generated_maven_project.sh |  2 +-
 .../build_generated_tdapi_maven_project.sh    |  2 +-
 src/main/tdapi-java/module-info.java          |  3 +
 src/main/tdapi-project-src/pom.template.xml   | 98 ++++++++++++++-----
 4 files changed, 80 insertions(+), 25 deletions(-)
 create mode 100644 src/main/tdapi-java/module-info.java

diff --git a/scripts/core/build_generated_maven_project.sh b/scripts/core/build_generated_maven_project.sh
index a85657d..40c33fd 100755
--- a/scripts/core/build_generated_maven_project.sh
+++ b/scripts/core/build_generated_maven_project.sh
@@ -2,7 +2,7 @@
 cd ../../generated
 
 [ -f ./src/main/java/it/tdlight/jni/TdApi.java ] && rm ./src/main/java/it/tdlight/jni/TdApi.java
-mvn -B -q clean package
+mvn -B clean install
 
 echo "Done."
 exit 0
diff --git a/scripts/core/build_generated_tdapi_maven_project.sh b/scripts/core/build_generated_tdapi_maven_project.sh
index b7cd947..d5634f7 100755
--- a/scripts/core/build_generated_tdapi_maven_project.sh
+++ b/scripts/core/build_generated_tdapi_maven_project.sh
@@ -1,7 +1,7 @@
 #!/bin/bash -e
 cd ../../generated
 
-mvn -B -q clean package
+mvn -B clean install
 
 echo "Done."
 exit 0
diff --git a/src/main/tdapi-java/module-info.java b/src/main/tdapi-java/module-info.java
new file mode 100644
index 0000000..9f8c0bc
--- /dev/null
+++ b/src/main/tdapi-java/module-info.java
@@ -0,0 +1,3 @@
+module tdlight.api {
+	exports it.tdlight.jni;
+}
diff --git a/src/main/tdapi-project-src/pom.template.xml b/src/main/tdapi-project-src/pom.template.xml
index 66f5106..d0b2fd6 100644
--- a/src/main/tdapi-project-src/pom.template.xml
+++ b/src/main/tdapi-project-src/pom.template.xml
@@ -69,15 +69,6 @@
 					</execution>
 				</executions>
 			</plugin>
-			<plugin>
-				<artifactId>maven-compiler-plugin</artifactId>
-				<version>3.8.1</version>
-				<configuration>
-					<encoding>UTF-8</encoding>
-					<source>1.8</source>
-					<target>1.8</target>
-				</configuration>
-			</plugin>
 			<plugin>
 				<groupId>org.codehaus.mojo</groupId>
 				<artifactId>flatten-maven-plugin</artifactId>
@@ -103,9 +94,83 @@
 					</execution>
 				</executions>
 			</plugin>
+			<!-- ensure the project is compiling with JDK 9+ -->
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-enforcer-plugin</artifactId>
+				<version>3.0.0-M3</version>
+				<executions>
+					<execution>
+						<id>enforce-jdk9</id>
+						<goals>
+							<goal>enforce</goal>
+						</goals>
+						<configuration>
+							<rules>
+								<requireJavaVersion>
+									<version>[1.9,)</version>
+									<message>JDK 9+ is required for compilation</message>
+								</requireJavaVersion>
+							</rules>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+			<!-- compile sources -->
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>3.8.1</version>
+				<configuration>
+					<encoding>UTF-8</encoding>
+				</configuration>
+				<executions>
+					<!-- disable default phase due to fixed id and position in lifecycle -->
+					<execution>
+						<id>default-compile</id>
+						<phase>none</phase>
+						<!-- specify source/target for IDE integration -->
+						<configuration>
+							<release>9</release>
+						</configuration>
+					</execution>
+					<!-- compile sources with Java 9 to generate and validate module-info.java -->
+					<execution>
+						<id>java-9-module-compile</id>
+						<goals>
+							<goal>compile</goal>
+						</goals>
+						<configuration>
+							<release>9</release>
+						</configuration>
+					</execution>
+					<!-- recompile sources as Java 8 to overwrite Java 9 class files, except module-info.java -->
+					<execution>
+						<id>java-8-compile</id>
+						<goals>
+							<goal>compile</goal>
+						</goals>
+						<configuration>
+							<!-- specify JDK 9+ release flag to ensure no classes/methods later than Java 8 are used accidentally -->
+							<release>8</release>
+							<!-- exclude module-info.java from the compilation, as it is unsupported by Java 8 -->
+							<excludes>
+								<exclude>module-info.java</exclude>
+							</excludes>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
 			<plugin>
 				<artifactId>maven-jar-plugin</artifactId>
-				<version>3.0.2</version>
+				<version>3.2.0</version>
+				<configuration>
+					<archive>
+						<manifestEntries>
+							<Multi-Release>true</Multi-Release>
+						</manifestEntries>
+					</archive>
+				</configuration>
 			</plugin>
 			<plugin>
 				<artifactId>maven-install-plugin</artifactId>
@@ -115,19 +180,6 @@
 				<artifactId>maven-deploy-plugin</artifactId>
 				<version>2.8.2</version>
 			</plugin>
-			<plugin>
-				<groupId>org.apache.maven.plugins</groupId>
-				<artifactId>maven-shade-plugin</artifactId>
-				<version>3.2.4</version>
-				<executions>
-					<execution>
-						<phase>package</phase>
-						<goals>
-							<goal>shade</goal>
-						</goals>
-					</execution>
-				</executions>
-			</plugin>
 		</plugins>
 	</build>
 </project>