Convert from JUnit 4 to JUnit 5

Author: cowtowncoder

VERSION.txt

@@ -3,6 +3,10 @@ Java ClassMate project: licensed under Apache License 2.0
 
 Release notes:
 
+1.8.1 (not yet released)
+
+- Upgrade to JUnit 5
+
 1.8.0 (10-Oct-2026)
 
 #125: Generic array types compare equal and collide in the resolver cache

pom.xml

@@ -56,11 +56,11 @@ com.fasterxml.classmate.*;version=${project.version}
     </organization>
 
     <dependencies>
-        <!-- and for testing, JUnit is needed -->
+        <!-- and for testing, JUnit 5 is needed -->
         <dependency>
-            <groupId>junit</groupId>
-            <artifactId>junit</artifactId>
-            <version>${version.junit}</version>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>${version.junit5}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>

src/test/java/com/fasterxml/classmate/AnnotationInclusionTest.java

@@ -1,8 +1,12 @@
 package com.fasterxml.classmate;
 
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
 public class AnnotationInclusionTest
     extends BaseTest
 {
+    @Test
     public void testValues() {  // stupid test for code coverage (being pedantic here)
         includesEnum(AnnotationInclusion.DONT_INCLUDE);
         includesEnum(AnnotationInclusion.INCLUDE_AND_INHERIT);

src/test/java/com/fasterxml/classmate/AnnotationsTest.java

@@ -1,34 +1,40 @@
 package com.fasterxml.classmate;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import java.lang.annotation.Annotation;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.reflect.Method;
 
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.*;
 
 public class AnnotationsTest
 {
     @Retention(RetentionPolicy.RUNTIME)
     private static @interface Marker { }
 
-    @Test @Marker
+    // Annotation with a property, to verify `toString()` output
+    @Retention(RetentionPolicy.RUNTIME)
+    private static @interface Configured {
+        int timeout() default 0;
+    }
+
+    @Test @Marker @Configured
     public void addAsDefault() throws Exception {
         Annotations annotations = new Annotations();
         Method thisMethod = AnnotationsTest.class.getDeclaredMethod("addAsDefault");
 
-        assertNull(annotations.get(Test.class));
+        assertNull(annotations.get(Configured.class));
         assertNull(annotations.get(Marker.class));
 
-        Annotation testAnnotation = thisMethod.getAnnotation(Test.class);
+        Annotation testAnnotation = thisMethod.getAnnotation(Configured.class);
         annotations.addAsDefault(testAnnotation);
 
         Annotation markerAnnotation = thisMethod.getAnnotation(Marker.class);
         annotations.addAsDefault(markerAnnotation);
 
-        assertNotNull(annotations.get(Test.class));
+        assertNotNull(annotations.get(Configured.class));
         assertNotNull(annotations.get(Marker.class));
 
         assertEquals(2, annotations.size());
@@ -43,7 +49,7 @@ public void size() throws Exception {
 
         assertEquals(0, annotations.size());
 
-        Annotation testAnnotation = thisMethod.getAnnotation(Test.class);
+        Annotation testAnnotation = thisMethod.getAnnotation(Configured.class);
         annotations.addAsDefault(testAnnotation);
 
         assertEquals(1, annotations.size());
@@ -61,20 +67,14 @@ public void annotationsToSize() throws Exception {
 
         assertEquals("[null]", annotations.toString());
 
-        Annotation testAnnotation = thisMethod.getAnnotation(Test.class);
+        Annotation testAnnotation = thisMethod.getAnnotation(Configured.class);
         annotations.addAsDefault(testAnnotation);
 
         // order is unspecified as the internal representation is a HashMap; just assert the constituent parts are present
         String asString = _normalize(annotations.toString());
-        assertTrue(asString.contains("{interface org.junit.Test=@org.junit.Test("));
-        assertTrue(asString.contains("timeout=0"));
-
-        // 15-Nov-2016, tatu: Java 9 changes description slightly, need to modify
-        // 05-Dec-2025, tatu: Java 21 adds further variation
-        if (!(asString.contains("expected=class org.junit.Test.None") // until Java 8
-                || asString.contains("expected=org.junit.Test.None"))) {
-            fail("No 'expected' in: "+asString);
-        }
+        assertTrue(asString.contains("{interface com.fasterxml.classmate.AnnotationsTest.Configured=@com.fasterxml.classmate.AnnotationsTest.Configured("),
+                asString);
+        assertTrue(asString.contains("timeout=0"), asString);
 
         Annotation markerAnnotation = thisMethod.getAnnotation(Marker.class);
         annotations.addAsDefault(markerAnnotation);
@@ -85,18 +85,13 @@ public void annotationsToSize() throws Exception {
         if (!asString.contains(exp)) {
             fail("Expected: ["+exp+"]\nin ["+asString+"]");
         }
-        assertTrue(asString.contains("interface org.junit.Test=@org.junit.Test"));
-        assertTrue(asString.contains("timeout=0"));
-        // 15-Nov-2016, tatu: Java 9 changes description slightly, need to modify
-        // 05-Dec-2025, tatu: Java 21 adds further variation
-        if (!(asString.contains("expected=class org.junit.Test.None") // until Java 8
-                || asString.contains("expected=org.junit.Test.None"))) {
-            fail("No 'expected' in: "+asString);
-        }
+        assertTrue(asString.contains("interface com.fasterxml.classmate.AnnotationsTest.Configured=@com.fasterxml.classmate.AnnotationsTest.Configured("),
+                asString);
+        assertTrue(asString.contains("timeout=0"), asString);
     }
 
     private static String _normalize(String str) {
-        // 05-Dec-2025, tatu: Java 21 changes from "org.junit.Test$None" to "org.junit.Test.None"
+        // Nested type names use '$' on some JDKs and '.' on others
         String str2;
         while ((str2 = str.replace('$', '.')) != str) {
             str = str2;

src/test/java/com/fasterxml/classmate/BaseTest.java

@@ -1,5 +1,7 @@
 package com.fasterxml.classmate;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
@@ -8,9 +10,8 @@
 import com.fasterxml.classmate.members.RawMember;
 import com.fasterxml.classmate.members.ResolvedMember;
 
-import junit.framework.TestCase;
 
-public abstract class BaseTest extends TestCase
+public abstract class BaseTest
 {
     protected void verifyException(Throwable e, String... matches)
     {

src/test/java/com/fasterxml/classmate/MemberResolver132Test.java

@@ -1,5 +1,8 @@
 package com.fasterxml.classmate;
 
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
 import java.util.*;
 
 import com.fasterxml.classmate.members.ResolvedMethod;
@@ -45,6 +48,7 @@ static abstract class GSub<T> implements GMid<T> { }
     private final TypeResolver _typeResolver = new TypeResolver();
     private final MemberResolver _memberResolver = new MemberResolver(_typeResolver);
 
+    @Test
     public void testInterfaceViaTypeParameter()
     {
         ResolvedType outer = _verifyViaContext(_typeResolver.resolve(MidI.class, String.class),
@@ -55,13 +59,15 @@ public void testInterfaceViaTypeParameter()
         assertEquals(OuterI.class, _findMethod(outer, "get").getReturnType().getErasedType());
     }
 
+    @Test
     public void testClassViaTypeParameter()
     {
         _verifyViaContext(_typeResolver.resolve(MidC.class, String.class), OuterC.class, "get", "top");
         _verifyViaContext(_typeResolver.resolve(MidI2.class, String.class), OuterC2.class, "get", "top");
     }
 
     // Self-reference itself as the type to resolve members of
+    @Test
     public void testSelfReferenceAsMainType()
     {
         ResolvedType selfRef = _typeResolver.resolve(OuterI.class)
@@ -72,6 +78,7 @@ public void testSelfReferenceAsMainType()
 
     // Self-referential supertypes only valid within their resolution context must
     // be replaced with stand-alone types
+    @Test
     public void testIncompleteSupertypes()
     {
         ResolvedType midJ = _param(_typeResolver.resolve(OutJ.class));
@@ -85,6 +92,7 @@ public void testIncompleteSupertypes()
         _verifyRef(outerK, OutK.class);
     }
 
+    @Test
     public void testSubtypeOfIncompleteType()
     {
         ResolvedType midJ = _param(_typeResolver.resolve(OutJ.class));

src/test/java/com/fasterxml/classmate/MemberResolver133Test.java

@@ -1,5 +1,8 @@
 package com.fasterxml.classmate;
 
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
 import com.fasterxml.classmate.members.ResolvedField;
 import com.fasterxml.classmate.members.ResolvedMethod;
 import com.fasterxml.classmate.types.ResolvedRecursiveType;
@@ -32,16 +35,19 @@ public static class RawSelf<T extends RawSelf> extends Base<T> { }
     private final TypeResolver _typeResolver = new TypeResolver();
     private final MemberResolver _memberResolver = new MemberResolver(_typeResolver);
 
+    @Test
     public void testGenericSelfReference()
     {
         _verify(Sym.class, Sym.class, Base.class);
     }
 
+    @Test
     public void testRawSelfReferenceInTypeParameter()
     {
         _verify(RB.class, RA.class, Object.class);
     }
 
+    @Test
     public void testBareRawSelfReference()
     {
         // sanity check: type parameter is a raw self-reference
@@ -53,6 +59,7 @@ public void testBareRawSelfReference()
     }
 
     // Self-reference passed directly to public `resolve()` methods
+    @Test
     public void testResolveSelfReference()
     {
         ResolvedType rawEnum = _typeResolver.resolve(Enum.class);
@@ -84,7 +91,7 @@ private void _verify(Class<?> type, Class<?> expValueType, Class<?> expParent)
         _verifyStandalone(value, expValueType, expParent);
 
         ResolvedType elem = arr.getArrayElementType();
-        assertFalse("Should not be self-reference: "+elem, elem instanceof ResolvedRecursiveType);
+        assertFalse(elem instanceof ResolvedRecursiveType, "Should not be self-reference: "+elem);
         assertEquals(elem, value);
         assertEquals(elem.hashCode(), value.hashCode());
         assertEquals(elem.getFullDescription(), value.getFullDescription());
@@ -101,7 +108,7 @@ private void _verify(Class<?> type, Class<?> expValueType, Class<?> expParent)
 
     private void _verifyStandalone(ResolvedType type, Class<?> expType, Class<?> expParent)
     {
-        assertFalse("Should not be self-reference: "+type, type instanceof ResolvedRecursiveType);
+        assertFalse(type instanceof ResolvedRecursiveType, "Should not be self-reference: "+type);
         assertEquals(expType, type.getErasedType());
         assertNotNull(type.getParentClass());
         assertEquals(expParent, type.getParentClass().getErasedType());

src/test/java/com/fasterxml/classmate/MemberResolverTest.java

@@ -1,5 +1,9 @@
 package com.fasterxml.classmate;
 
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeEach;
+import static org.junit.jupiter.api.Assertions.*;
+
 import java.lang.reflect.Method;
 import java.util.*;
 
@@ -81,8 +85,8 @@ static class SimpleClass
 
     protected TypeResolver typeResolver;
 
-    @Override
-    protected void setUp()
+    @BeforeEach
+    public void setUp()
     {
         // Let's use a single instance for all tests, to increase chance of seeing failures
         typeResolver = new TypeResolver();
@@ -97,6 +101,7 @@ protected void setUp()
     /**
      * Test for most basic thing; type hierarchy resolution 
      */
+    @Test
     public void testSimpleHierarchy()
     {
         MemberResolver mr = new MemberResolver(typeResolver);
@@ -112,6 +117,7 @@ public void testSimpleHierarchy()
         assertSame(BaseClass.class, types.get(1).getErasedType());
     }
 
+    @Test
     public void testSimpleHierarchyWithMixins()
     {
         MemberResolver mr = new MemberResolver(typeResolver);
@@ -151,6 +157,7 @@ public void testSimpleHierarchyWithMixins()
     /**
      * Test for checking basic member detection for super type.
      */
+    @Test
     public void testMembersForSupertype()
     {
         MemberResolver mr = new MemberResolver(typeResolver);
@@ -177,6 +184,7 @@ public void testMembersForSupertype()
      * Test for checking basic aggregation with two types (subtype that
      * extends supertype)
      */
+    @Test
     public void testAggregationForSubtype()
     {
         MemberResolver mr = new MemberResolver(typeResolver);
@@ -186,6 +194,7 @@ public void testAggregationForSubtype()
         verifySubtypeAggregate(bean);
     }
 
+    @Test
     public void testAggregationForSubtypeAndDummyMixin()
     {
         MemberResolver mr = new MemberResolver(typeResolver);
@@ -199,6 +208,7 @@ public void testAggregationForSubtypeAndDummyMixin()
         verifySubtypeAggregate(bean);
     }
 
+    @Test
     public void testIncludeObject()
     {
         ResolvedType simpleResolvedType = typeResolver.resolve(SimpleClass.class);
@@ -221,6 +231,7 @@ public void testIncludeObject()
         assertEquals(1, simpleResolvedTypeWithMembers.getMemberFields().length);
     }
 
+    @Test
     public void testFilters()
     {
         ResolvedType simpleResolvedType = typeResolver.resolve(SimpleClass.class);
@@ -293,6 +304,7 @@ public void testFilters()
     //    like this. And since this breaks with JDK 17 (probably due to additional
     //    interfaces in JDK types), will comment out.
 /*
+    @Test
     public void testAddOverridesFromInterfaces() throws IllegalAccessException, InvocationTargetException
     {
         ResolvedType resolvedType = typeResolver.resolve(MemberResolver.class);
@@ -340,6 +352,7 @@ public void testAddOverridesFromInterfaces() throws IllegalAccessException, Invo
     }
     */
 
+    @Test
     public void testGatherTypesWithInterfaces() throws Exception
     {
         ResolvedType resolvedType = typeResolver.resolve(MemberResolver.class);
@@ -374,6 +387,7 @@ public void testGatherTypesWithInterfaces() throws Exception
         assertEquals(2, types.size());
     }
 
+    @Test
     public void testJavaLangObject30() throws Exception
     {
         MemberResolver memberResolver = new MemberResolver(typeResolver);

src/test/java/com/fasterxml/classmate/OddJDKTypesTest.java

@@ -1,11 +1,15 @@
 package com.fasterxml.classmate;
 
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
 import java.util.*;
 
 public class OddJDKTypesTest extends BaseTest
 {
     // Simple test, based on issues Jackson's type resolver had with inner
     // classes of JDK (Hash)Map
+    @Test
     public void testJDKMaps()
     {
         TypeResolver resolver = new TypeResolver();

src/test/java/com/fasterxml/classmate/ResolvedTypeTest.java

@@ -1,10 +1,12 @@
 package com.fasterxml.classmate;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 import java.io.Serializable;
 import java.nio.CharBuffer;
 import java.util.List;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import com.fasterxml.classmate.types.ResolvedArrayType;
 import com.fasterxml.classmate.types.ResolvedInterfaceType;