HHH-12946 Remove unnecessary dependencies when building with JDK9+

We don't need to depend on JAXB's compiler (XJC) in our modules,
we just need the dependency in specific tasks during the build.
In particular we don't want users to transitively depend on XJC.

Also, we don't need an explicit dependency to JAXB in every module,
having one in hibernate-core is enough.

gradle/java-module.gradle

@@ -108,35 +108,20 @@ dependencies {
 		testRuntime( libraries.hana )
 	}
 
-
 	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 	// Java 9 ftw!
 	if ( JavaVersion.current().isJava9Compatible() ) {
-		// The JDK used to run Gradle is Java 9+, and we assume that that is the same
-		//		JDK for executing tasks
-		compile( libraries.jaxb_api )
-		compile( libraries.jaxb_runtime )
-		compile( libraries.jaxb_xjc )
-		compile( libraries.jaxb2_basics )
-		compile( libraries.jaxb2_basics_ant )
+		// In order for code generated by jpamodelgen to be compiled successfully,
+		// we need the @javax.annotation.Generated annotation to be in the classpath,
+		// and it's no longer in the JDK starting with JDK9
+		// (though @javax.annotation.processing.Generated is available in JDK9).
+		// Thus we need an additional dependency.
+		// See also https://hibernate.atlassian.net/browse/HHH-12990
 		compile( libraries.jsr250_api )
-
-		testCompile( libraries.jaxb_api )
-		testCompile( libraries.jaxb_runtime )
-		testCompile( libraries.jaxb_xjc )
-		testCompile( libraries.jaxb2_basics )
-		testCompile( libraries.jaxb2_basics_ant )
 		testCompile( libraries.jsr250_api )
-
-		testRuntime( libraries.jaxb_api )
-		testRuntime( libraries.jaxb_runtime )
-		testRuntime( libraries.jaxb_xjc )
-		testRuntime( libraries.jaxb2_basics )
-		testRuntime( libraries.jaxb2_basics_ant )
 	}
 	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-
 	// Mac-specific
 	project.ext.toolsJar = file("${System.getProperty('java.home')}/../lib/tools.jar")
 	if ( project.toolsJar.exists() ) {

hibernate-core/hibernate-core.gradle

@@ -27,6 +27,9 @@ dependencies {
     // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     // Java 9 ftw!
     if ( JavaVersion.current().isJava9Compatible() ) {
+        compile( libraries.jaxb_api )
+        compile( libraries.jaxb_runtime )
+
         xjc( libraries.jaxb_runtime )
         xjc( libraries.jaxb_xjc )
         xjc( libraries.jaxb2_basics )

tooling/metamodel-generator/hibernate-jpamodelgen.gradle

@@ -24,6 +24,8 @@ dependencies {
 	// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 	// Java 9 ftw!
 	if ( JavaVersion.current().isJava9Compatible() ) {
+		compile( libraries.jaxb_api )
+
 		xjc( libraries.jaxb_runtime )
 		xjc( libraries.jaxb_xjc )
 		xjc( libraries.jaxb2_basics )