diff --git a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkContractTest.java b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkContractTest.java
index e9bc45040..c5bd2a13f 100644
--- a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkContractTest.java
+++ b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkContractTest.java
@@ -38,13 +38,13 @@
 public abstract class FrameworkContractTest {
 
 	@Test
-	public void exists() {
+	public final void exists() {
 		assertNotNull(framework());
 		assertTrue(framework().isPresent());
 	}
 
 	@Test
-	public void canResolveRequirements() {
+	public final void canResolveRequirements() {
 		Registry<StringServiceId, ResolvedRequirements> registry = framework().get().requirementsRegistry().get();
 		assertNotNull(registry);
 		assertNotNull(registry.services());
@@ -52,12 +52,12 @@ public void canResolveRequirements() {
 	}
 
 	@Test
-	public void prohibitsRequirementsResolutionExtension() {
+	public final void prohibitsRequirementsResolutionExtension() {
 		assertTrue(readOnly(framework().get().requirementsRegistry().get()));
 	}
 
 	@Test
-	public void prohibitsInjectionIntoRequirementResolutionServices() {
+	public final void prohibitsInjectionIntoRequirementResolutionServices() {
 		Registry<StringServiceId, ResolvedRequirements> registry = framework().get().requirementsRegistry().get();
 		int before = registry.services().size();
 		registry.services().add(new FakeResolvedRequirements());
diff --git a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkRequirementResolutionServiceTest.java b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkRequirementResolutionServiceTest.java
index 553c4b03b..21902aed5 100644
--- a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkRequirementResolutionServiceTest.java
+++ b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/FrameworkRequirementResolutionServiceTest.java
@@ -34,12 +34,12 @@
 public abstract class FrameworkRequirementResolutionServiceTest extends ReadOnlyCollectionTest<ResolvedRequirements> {
 
 	@Override
-	protected Supplier<Collection<ResolvedRequirements>> collection() {
+	protected final Supplier<Collection<ResolvedRequirements>> collection() {
 		return () -> framework().get().requirementsRegistry().get().services();
 	}
 
 	@Override
-	protected ResolvedRequirements single() {
+	protected final ResolvedRequirements single() {
 		return new FakeResolvedRequirements();
 	}
 
diff --git a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ReadOnlyCollectionTest.java b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ReadOnlyCollectionTest.java
index 02b7e578e..11f831284 100644
--- a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ReadOnlyCollectionTest.java
+++ b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ReadOnlyCollectionTest.java
@@ -34,13 +34,13 @@
 public abstract class ReadOnlyCollectionTest<T> {
 
 	@Test
-	public void prohibitsInjections() {
+	public final void prohibitsInjections() {
 		testInterferenceResistence(shared -> shared.add(single()));
 		testInterferenceResistence(shared -> shared.addAll(Collections.singleton(single())));
 	}
 
 	@Test
-	public void prohibitsRemovals() {
+	public final void prohibitsRemovals() {
 		assumeTrue(collection().get().size() > 0);
 		testInterferenceResistence(Collection::clear);
 		testInterferenceResistence(shared -> shared.retainAll(Collections.emptyList()));
diff --git a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ResolvedRequirementsContractTest.java b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ResolvedRequirementsContractTest.java
index ec114503e..3ea85129f 100644
--- a/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ResolvedRequirementsContractTest.java
+++ b/tests/org.eclipse.passage.lic.api.tests/src/org/eclipse/passage/lic/api/tests/ResolvedRequirementsContractTest.java
@@ -29,7 +29,7 @@
 public abstract class ResolvedRequirementsContractTest extends ReadOnlyCollectionTest<Requirement> {
 
 	@Override
-	protected Supplier<Collection<Requirement>> collection() {
+	protected final Supplier<Collection<Requirement>> collection() {
 		return service()::all;
 	}