only use @Transactional from Spring (not JavaX) and use readOnly=true where possible

build.gradle

@@ -90,7 +90,8 @@ openapiProcessor {
     }
 }
 sourceSets.main.java.srcDir 'build/generated/sources/openapi'
-compileJava.dependsOn('processSpring')
+project.tasks.processResources.dependsOn('processSpring')
+project.tasks.compileJava.dependsOn('processSpring')
 
 spotless {
     java {

src/main/java/net/hostsharing/hsadminng/hs/hscustomer/CustomerController.java

@@ -5,10 +5,10 @@ import net.hostsharing.hsadminng.generated.api.v1.api.CustomersApi;
 import net.hostsharing.hsadminng.generated.api.v1.model.CustomerResource;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder;
 
-import javax.transaction.Transactional;
 import java.util.List;
 import java.util.UUID;
 
@@ -26,7 +26,7 @@ public class CustomerController implements CustomersApi {
     private CustomerRepository customerRepository;
 
     @Override
-    @Transactional
+    @Transactional(readOnly = true)
     public ResponseEntity<List<CustomerResource>> listCustomers(
         String userName,
         String assumedRoles,

src/main/java/net/hostsharing/hsadminng/hs/hspackage/PackageController.java

@@ -7,9 +7,9 @@ import net.hostsharing.hsadminng.generated.api.v1.model.PackageResource;
 import net.hostsharing.hsadminng.generated.api.v1.model.PackageUpdateResource;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.bind.annotation.RestController;
 
-import javax.transaction.Transactional;
 import java.util.List;
 import java.util.UUID;
 
@@ -26,7 +26,7 @@ public class PackageController implements PackagesApi {
     private PackageRepository packageRepository;
 
     @Override
-    @Transactional
+    @Transactional(readOnly = true)
     public ResponseEntity<List<PackageResource>> listPackages(
         String userName,
         String assumedRoles,

src/main/java/net/hostsharing/hsadminng/rbac/rbacgrant/RbacGrantController.java

@@ -2,16 +2,15 @@ package net.hostsharing.hsadminng.rbac.rbacgrant;
 
 import net.hostsharing.hsadminng.context.Context;
 import net.hostsharing.hsadminng.generated.api.v1.api.RbacgrantsApi;
-import net.hostsharing.hsadminng.generated.api.v1.api.RbacrolesApi;
 import net.hostsharing.hsadminng.generated.api.v1.model.RbacGrantResource;
-import net.hostsharing.hsadminng.generated.api.v1.model.RbacRoleResource;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder;
 
-import javax.transaction.Transactional;
 import java.util.List;
+import java.util.UUID;
 
 import static net.hostsharing.hsadminng.Mapper.map;
 import static net.hostsharing.hsadminng.Mapper.mapList;
@@ -27,7 +26,7 @@ public class RbacGrantController implements RbacgrantsApi {
     private RbacGrantRepository rbacGrantRepository;
 
     @Override
-    @Transactional
+    @Transactional(readOnly = true)
     public ResponseEntity<List<RbacGrantResource>> listUserGrants(
         final String currentUser,
         final String assumedRoles) {

src/main/java/net/hostsharing/hsadminng/rbac/rbacrole/RbacRoleController.java

@@ -5,9 +5,9 @@ import net.hostsharing.hsadminng.generated.api.v1.api.RbacrolesApi;
 import net.hostsharing.hsadminng.generated.api.v1.model.RbacRoleResource;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.bind.annotation.RestController;
 
-import javax.transaction.Transactional;
 import java.util.List;
 
 import static net.hostsharing.hsadminng.Mapper.mapList;
@@ -23,7 +23,7 @@ public class RbacRoleController implements RbacrolesApi {
     private RbacRoleRepository rbacRoleRepository;
 
     @Override
-    @Transactional
+    @Transactional(readOnly = true)
     public ResponseEntity<List<RbacRoleResource>> listRoles(
         final String currentUser,
         final String assumedRoles) {

src/main/java/net/hostsharing/hsadminng/rbac/rbacuser/RbacUserController.java

@@ -6,11 +6,11 @@ import net.hostsharing.hsadminng.generated.api.v1.model.RbacUserPermissionResour
 import net.hostsharing.hsadminng.generated.api.v1.model.RbacUserResource;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.servlet.mvc.method.annotation.MvcUriComponentsBuilder;
 
 import javax.persistence.EntityManager;
-import javax.transaction.Transactional;
 import java.util.List;
 import java.util.UUID;
 
@@ -48,7 +48,7 @@ public class RbacUserController implements RbacusersApi {
     }
 
     @Override
-    @Transactional
+    @Transactional(readOnly=true)
     public ResponseEntity<List<RbacUserResource>> listUsers(
         @RequestHeader(name = "current-user") final String currentUserName,
         @RequestHeader(name = "assumed-roles", required = false) final String assumedRoles,
@@ -62,7 +62,7 @@ public class RbacUserController implements RbacusersApi {
     }
 
     @Override
-    @Transactional
+    @Transactional(readOnly=true)
     public ResponseEntity<List<RbacUserPermissionResource>> listUserPermissions(
         @RequestHeader(name = "current-user") final String currentUserName,
         @RequestHeader(name = "assumed-roles", required = false) final String assumedRoles,

src/test/java/net/hostsharing/hsadminng/arch/ArchUnitTest.java

@@ -8,8 +8,7 @@ import org.junit.jupiter.api.Test;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.web.bind.annotation.RestController;
 
-import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.classes;
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.*;
-import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.methods;
 import static com.tngtech.archunit.library.dependencies.SlicesRuleDefinition.slices;
 
 @AnalyzeClasses(packages = ArchUnitTest.NET_HOSTSHARING_HSADMINNG)
@@ -66,6 +65,22 @@ public class ArchUnitTest {
         .should().haveSimpleNameEndingWith("AcceptanceTest")
         .orShould().haveSimpleNameNotContaining("AcceptanceTest$");
 
+    @ArchTest
+    @SuppressWarnings("unused")
+    public static final ArchRule doNotUseJavaxTransactionAnnotationAtClassLevel = noClasses()
+        .should().beAnnotatedWith(javax.transaction.Transactional.class.getName())
+        .as("Use @%s instead of @%s." .formatted(
+            org.springframework.transaction.annotation.Transactional.class.getName(),
+            javax.transaction.Transactional.class));
+
+    @ArchTest
+    @SuppressWarnings("unused")
+    public static final ArchRule doNotUseJavaxTransactionAnnotationAtMethodLevel = noMethods()
+        .should().beAnnotatedWith(javax.transaction.Transactional.class)
+        .as("Use @%s instead of @%s." .formatted(
+            org.springframework.transaction.annotation.Transactional.class.getName(),
+            javax.transaction.Transactional.class.getName()));
+
     @Test
     public void everythingShouldBeFreeOfCycles() {
         slices().matching("net.hostsharing.hsadminng.(*)..").should().beFreeOfCycles();

src/test/java/net/hostsharing/hsadminng/rbac/rbacgrant/RbacGrantControllerAcceptanceTest.java

@@ -24,6 +24,7 @@ import java.util.List;
 import java.util.UUID;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assumptions.assumeThat;
 import static org.hamcrest.CoreMatchers.containsString;
 
 @SpringBootTest(
@@ -31,7 +32,7 @@ import static org.hamcrest.CoreMatchers.containsString;
     classes = { HsadminNgApplication.class, JpaAttempt.class }
 )
 @Accepts({ "GRT:S(Schema)" })
-@Transactional(propagation = Propagation.NEVER)
+@Transactional(readOnly = true, propagation = Propagation.NEVER)
 class RbacGrantControllerAcceptanceTest {
 
     @LocalServerPort
@@ -64,8 +65,8 @@ class RbacGrantControllerAcceptanceTest {
 
             // given
             final var givenNewUserName = "test-user-" + RandomStringUtils.randomAlphabetic(8) + "@example.com";
-            final String givenCurrentUserPackageAdmin = "aaa00@aaa.example.com";
+            final var givenCurrentUserPackageAdmin = "aaa00@aaa.example.com";
-            final String givenAssumedRole = "package#aaa00.admin";
+            final var givenAssumedRole = "package#aaa00.admin";
             final var givenOwnPackageAdminRole = "package#aaa00.admin";
 
             // when
@@ -105,8 +106,8 @@ class RbacGrantControllerAcceptanceTest {
 
             // given
             final var givenNewUserName = "test-user-" + RandomStringUtils.randomAlphabetic(8) + "@example.com";
-            final String givenCurrentUserPackageAdmin = "aaa00@aaa.example.com";
+            final var givenCurrentUserPackageAdmin = "aaa00@aaa.example.com";
-            final String givenAssumedRole = "package#aaa00.admin";
+            final var givenAssumedRole = "package#aaa00.admin";
             final var givenAlienPackageAdminRole = "package#aab00.admin";
 
             // when

src/test/java/net/hostsharing/hsadminng/rbac/rbacuser/RbacUserRepositoryIntegrationTest.java

@@ -9,7 +9,6 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.orm.jpa.JpaSystemException;
-import org.springframework.test.annotation.Commit;
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.transaction.annotation.Propagation;
 import org.springframework.transaction.annotation.Transactional;
@@ -59,7 +58,6 @@ class RbacUserRepositoryIntegrationTest {
         }
 
         @Test
-        @Commit
         @Transactional(propagation = Propagation.NEVER)
         void anyoneCanCreateTheirOwnUser_committed() {