diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsFactory.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsFactory.java
index 81015a6ff..0a145b362 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsFactory.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsFactory.java
@@ -2,13 +2,13 @@
 
 import java.io.*;
 import java.net.URL;
-import java.util.*;
+import java.util.Map;
+import java.util.Properties;
 
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.format.InputAccessor;
 import com.fasterxml.jackson.core.format.MatchStrength;
 import com.fasterxml.jackson.core.io.IOContext;
-
 import com.fasterxml.jackson.dataformat.javaprop.impl.PropertiesBackedGenerator;
 import com.fasterxml.jackson.dataformat.javaprop.impl.WriterBackedGenerator;
 import com.fasterxml.jackson.dataformat.javaprop.io.Latin1Reader;
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsGenerator.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsGenerator.java
index 283cac465..bfe2ac647 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsGenerator.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsGenerator.java
@@ -1,6 +1,6 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import java.io.*;
+import java.io.IOException;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.util.Arrays;
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsMapper.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsMapper.java
index e24507181..b3cbdc881 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsMapper.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsMapper.java
@@ -1,18 +1,12 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
 import java.io.IOException;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.Properties;
+import java.util.*;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.Version;
-import com.fasterxml.jackson.databind.DeserializationFeature;
-import com.fasterxml.jackson.databind.JavaType;
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.cfg.CoercionAction;
-import com.fasterxml.jackson.databind.cfg.CoercionInputShape;
-import com.fasterxml.jackson.databind.cfg.MapperBuilder;
+import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.cfg.*;
 
 public class JavaPropsMapper extends ObjectMapper
 {
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsParser.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsParser.java
index 01083b190..997890f66 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsParser.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/JavaPropsParser.java
@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import java.io.*;
+import java.io.IOException;
+import java.io.Writer;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.util.Map;
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/PropertiesBackedGenerator.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/PropertiesBackedGenerator.java
index 1e02c0c13..610209106 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/PropertiesBackedGenerator.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/PropertiesBackedGenerator.java
@@ -1,10 +1,10 @@
 package com.fasterxml.jackson.dataformat.javaprop.impl;
 
-import java.io.*;
+import java.io.IOException;
 import java.util.Map;
 import java.util.Properties;
 
-import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.core.ObjectCodec;
 import com.fasterxml.jackson.core.io.IOContext;
 import com.fasterxml.jackson.dataformat.javaprop.JavaPropsGenerator;
 
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/WriterBackedGenerator.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/WriterBackedGenerator.java
index 53b98d5e4..7921225c9 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/WriterBackedGenerator.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/impl/WriterBackedGenerator.java
@@ -1,8 +1,9 @@
 package com.fasterxml.jackson.dataformat.javaprop.impl;
 
-import java.io.*;
+import java.io.IOException;
+import java.io.Writer;
 
-import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.core.ObjectCodec;
 import com.fasterxml.jackson.core.io.IOContext;
 import com.fasterxml.jackson.dataformat.javaprop.JavaPropsGenerator;
 import com.fasterxml.jackson.dataformat.javaprop.io.JPropEscapes;
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropReadContext.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropReadContext.java
index 5aa0cf9e6..f4b0c5eca 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropReadContext.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropReadContext.java
@@ -1,8 +1,10 @@
 package com.fasterxml.jackson.dataformat.javaprop.io;
 
-import java.util.*;
+import java.util.Iterator;
+import java.util.Map;
 
-import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.core.JsonStreamContext;
+import com.fasterxml.jackson.core.JsonToken;
 import com.fasterxml.jackson.dataformat.javaprop.util.JPropNode;
 
 /**
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropWriteContext.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropWriteContext.java
index a857e7f3a..141778dd3 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropWriteContext.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/io/JPropWriteContext.java
@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.dataformat.javaprop.io;
 
-import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.core.JsonStreamContext;
 //import com.fasterxml.jackson.core.json.JsonWriteContext;
 
 public class JPropWriteContext
diff --git a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropNodeBuilder.java b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropNodeBuilder.java
index a00538da8..d1ffb4a72 100644
--- a/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropNodeBuilder.java
+++ b/properties/src/main/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropNodeBuilder.java
@@ -3,7 +3,7 @@
 import java.util.Map;
 import java.util.Properties;
 
-import com.fasterxml.jackson.dataformat.javaprop.*;
+import com.fasterxml.jackson.dataformat.javaprop.JavaPropsSchema;
 
 public class JPropNodeBuilder
 {
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayGenerationTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayGenerationTest.java
index 5eeac6c61..bd1440bca 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayGenerationTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayGenerationTest.java
@@ -3,12 +3,17 @@
 import java.util.Map;
 import java.util.Properties;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.dataformat.javaprop.util.Markers;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 public class ArrayGenerationTest extends ModuleTestBase
 {
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testPointListSimple() throws Exception
     {
         Points input = new Points
@@ -35,6 +40,7 @@ public void testPointListSimple() throws Exception
         }
     }
 
+    @Test
     public void testPointListWithIndex() throws Exception
     {
         JavaPropsSchema schema = JavaPropsSchema.emptySchema()
@@ -65,6 +71,7 @@ public void testPointListWithIndex() throws Exception
         }
     }
 
+    @Test
     public void testPointListWithCustomMarkers() throws Exception
     {
         JavaPropsSchema schema = JavaPropsSchema.emptySchema()
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayParsingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayParsingTest.java
index e2d53e1a5..4c896b79d 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayParsingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ArrayParsingTest.java
@@ -4,12 +4,14 @@
 import java.util.List;
 import java.util.Map;
 
-import com.fasterxml.jackson.annotation.JsonCreator;
-import com.fasterxml.jackson.annotation.JsonProperty;
-import com.fasterxml.jackson.annotation.JsonValue;
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.annotation.*;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectReader;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 public class ArrayParsingTest extends ModuleTestBase
 {
     static class ZKConfig {
@@ -57,6 +59,7 @@ static class StringArrayWrapper {
 
     private final ObjectMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testArrayWithBranch() throws Exception
     {
         // basically "extra" branch should become as first element, and
@@ -92,6 +95,7 @@ public void testArrayWithBranch() throws Exception
         assertTrue(ob instanceof Map);
     }
 
+    @Test
     public void testPointList() throws Exception
     {
         _testPointList(false, false);
@@ -129,6 +133,7 @@ private void _testPointList(boolean useBytes, boolean allowIndex) throws Excepti
         assertEquals(6, result.p.get(2).y);
     }
 
+    @Test
     public void testPointListWithIndex() throws Exception
     {
         _testPointListWithIndex(false);
@@ -153,6 +158,7 @@ private void _testPointListWithIndex(boolean useBytes) throws Exception
         assertEquals(4, result.p.get(1).y);
     }
 
+    @Test
     public void testZKPojo() throws Exception
     {
         _testZKPojo(false, false);
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/BinaryParsingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/BinaryParsingTest.java
index 79c3a6e32..3f7e65e28 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/BinaryParsingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/BinaryParsingTest.java
@@ -1,11 +1,13 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import static org.junit.Assert.assertArrayEquals;
-
 import java.nio.ByteBuffer;
 import java.util.Map;
 import java.util.Properties;
 
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
 public class BinaryParsingTest extends ModuleTestBase
 {
     // [dataformats-text#74]: problem with multiple binary fields
@@ -31,6 +33,7 @@ public MyBean(boolean bogus) {
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
     // [dataformats-text#74]
+    @Test
     public void testMultipleBinaryFields() throws Exception
     {
         final MyBean src = new MyBean(true);
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/CustomSeparatorsTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/CustomSeparatorsTest.java
index 27ba03b89..9950566b9 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/CustomSeparatorsTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/CustomSeparatorsTest.java
@@ -1,11 +1,16 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 public class CustomSeparatorsTest extends ModuleTestBase
 {
     private final ObjectMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testCustomPathSeparator() throws Exception
     {
         JavaPropsSchema schema = JavaPropsSchema.emptySchema()
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/DefaultConfigsTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/DefaultConfigsTest.java
index 395a54316..c96e5fac2 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/DefaultConfigsTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/DefaultConfigsTest.java
@@ -2,15 +2,17 @@
 
 import java.io.StringWriter;
 
-import com.fasterxml.jackson.core.JsonGenerator;
-import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.core.Version;
-import com.fasterxml.jackson.core.Versioned;
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.core.*;
+
+import static org.junit.jupiter.api.Assertions.*;
 
 public class DefaultConfigsTest extends ModuleTestBase
 {
     private final String ARTIFACT_ID = "jackson-dataformat-properties";
     
+    @Test
     public void testMapperBaseConfig()
     {
         JavaPropsMapper mapper = newPropertiesMapper();
@@ -19,6 +21,7 @@ public void testMapperBaseConfig()
         assertNotSame(mapper, copy);
     }
 
+    @Test
     public void testFactoryBaseConfig()
     {
         JavaPropsFactory f = JavaPropsFactory.builder().build();
@@ -32,6 +35,7 @@ public void testFactoryBaseConfig()
         assertFalse(f.canUseCharArrays());
     }
 
+    @Test
     public void testGeneratorConfig() throws Exception
     {
         JavaPropsFactory f = JavaPropsFactory.builder().build();
@@ -49,6 +53,7 @@ public void testGeneratorConfig() throws Exception
         gen.close();
     }
 
+    @Test
     public void testParserConfig() throws Exception
     {
         JavaPropsFactory f = new JavaPropsFactory();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/GenerationEscapingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/GenerationEscapingTest.java
index 7cbd2059e..d702647db 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/GenerationEscapingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/GenerationEscapingTest.java
@@ -1,13 +1,19 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import java.util.*;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 public class GenerationEscapingTest extends ModuleTestBase
 {
     private final ObjectMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testKeyEscaping() throws Exception
     {
         Map<String,String> input = new HashMap<>();
@@ -23,6 +29,7 @@ public void testKeyEscaping() throws Exception
         assertEquals("combo\\tkey=value\n", MAPPER.writeValueAsString(input));
     }
 
+    @Test
     public void testValueEscaping() throws Exception
     {
         /*
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/MapParsingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/MapParsingTest.java
index 505d00aa9..0e2bfd9e7 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/MapParsingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/MapParsingTest.java
@@ -2,8 +2,14 @@
 
 import java.util.Map;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+
 public class MapParsingTest extends ModuleTestBase
 {
     static class MapWrapper {
@@ -17,6 +23,7 @@ static class MapWrapper {
     /**********************************************************************
      */
 
+    @Test
     public void testMapWithBranchNoEscaping() throws Exception
     {
         ObjectMapper mapper = newPropertiesMapper();
@@ -37,6 +44,7 @@ public void testMapWithBranchNoEscaping() throws Exception
         assertEquals("fourth", ((Map<?,?>) w.map.get("ab\\")).get("c"));
     }
 
+    @Test
     public void testMapWithBranchBackslashEscape() throws Exception
     {
         JavaPropsMapper mapper = newPropertiesMapper();
@@ -75,6 +83,7 @@ public void testMapWithBranchBackslashEscape() throws Exception
         assertEquals("twelfth", ((Map<?,?>) w.map.get("xy\\.d")).get("ij"));
     }
 
+    @Test
     public void testMapWithBranchHashEscape() throws Exception
     {
         JavaPropsMapper mapper = newPropertiesMapper();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ModuleTestBase.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ModuleTestBase.java
index 6833c7a44..3a986ed2d 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ModuleTestBase.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/ModuleTestBase.java
@@ -1,19 +1,20 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.StringReader;
+import java.io.*;
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.List;
 
-import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonToken;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectReader;
-import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 
-public abstract class ModuleTestBase extends junit.framework.TestCase
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
+public abstract class ModuleTestBase
 {
     @JsonPropertyOrder({ "topLeft", "bottomRight" })
     protected static class Rectangle {
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/NumberDeserWithPropsTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/NumberDeserWithPropsTest.java
index 450e6eaba..c2a25237b 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/NumberDeserWithPropsTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/NumberDeserWithPropsTest.java
@@ -2,15 +2,15 @@
 
 import java.math.BigDecimal;
 
-import com.fasterxml.jackson.annotation.JsonProperty;
-import com.fasterxml.jackson.annotation.JsonSubTypes;
-import com.fasterxml.jackson.annotation.JsonTypeInfo;
-import com.fasterxml.jackson.annotation.JsonUnwrapped;
+import org.junit.jupiter.api.Test;
 
+import com.fasterxml.jackson.annotation.*;
 import com.fasterxml.jackson.core.StreamReadConstraints;
 import com.fasterxml.jackson.databind.JsonMappingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 // Tests copied from databind "JDKNumberDeserTest" (only a small subset)
 public class NumberDeserWithPropsTest extends ModuleTestBase
 {
@@ -59,6 +59,7 @@ static class NestedBigDecimalHolder2784 {
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
     // [databind#2644]
+    @Test
     public void testBigDecimalSubtypes() throws Exception
     {
         ObjectMapper mapper = propertiesMapperBuilder()
@@ -74,6 +75,7 @@ public void testBigDecimalSubtypes() throws Exception
     }
 
     // [databind#2784]
+    @Test
     public void testBigDecimalUnwrapped() throws Exception
     {
         // mapper.enable(DeserializationFeature.USE_BIG_DECIMAL_FOR_FLOATS);
@@ -82,6 +84,7 @@ public void testBigDecimalUnwrapped() throws Exception
         assertEquals(new BigDecimal("5.00"), result.holder.value);
     }
 
+    @Test
     public void testVeryBigDecimalUnwrapped() throws Exception
     {
         final int len = 1200;
@@ -95,11 +98,12 @@ public void testVeryBigDecimalUnwrapped() throws Exception
             MAPPER.readValue(DOC, NestedBigDecimalHolder2784.class);
             fail("expected JsonMappingException");
         } catch (JsonMappingException jme) {
-            assertTrue("unexpected message: " + jme.getMessage(),
-                    jme.getMessage().startsWith("Number value length (1200) exceeds the maximum allowed"));
+            assertTrue(jme.getMessage().startsWith("Number value length (1200) exceeds the maximum allowed"),
+                    "unexpected message: " + jme.getMessage());
         }
     }
 
+    @Test
     public void testVeryBigDecimalUnwrappedWithNumLenUnlimited() throws Exception
     {
         final int len = 1200;
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PrefixTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PrefixTest.java
index 1fa4d2a1a..056e490ca 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PrefixTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PrefixTest.java
@@ -3,10 +3,16 @@
 import java.util.Map;
 import java.util.Properties;
 
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+
 public class PrefixTest extends ModuleTestBase
 {
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testPrefixParsing() throws Exception {
         final String INPUT = "org.o1.firstName=Bob\n"
                 +"org.o1.lastName=Palmer\n"
@@ -21,6 +27,7 @@ public void testPrefixParsing() throws Exception {
         assertEquals("Black", result2.lastName);
     }
 
+    @Test
     public void testPrefixGeneration() throws Exception
     {
         FiveMinuteUser input = new FiveMinuteUser("Bob", "Palmer", true, Gender.MALE,
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PropertiesSupportTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PropertiesSupportTest.java
index f989e750b..f167e7686 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PropertiesSupportTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/PropertiesSupportTest.java
@@ -2,6 +2,10 @@
 
 import java.util.*;
 
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
 /**
  * Tests for extended functionality to work with JDK `Properties` Object
  * (as well as {@code java.util.Map}, since 2.10)
@@ -20,6 +24,7 @@ public void setValues(Map<String, String> values) {
 
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testSimpleEmployeeFromProperties() throws Exception
     {
         Properties props = new Properties();
@@ -29,6 +34,7 @@ public void testSimpleEmployeeFromProperties() throws Exception
     }
 
     // for [dataformats-text#139]
+    @Test
     public void testSimpleEmployeeFromMap() throws Exception
     {
         Map<String, String> map = new LinkedHashMap<>();
@@ -50,6 +56,7 @@ private void _verifySimple(Map<?,?> result)
         assertEquals("14", m2.get("b"));
     }
 
+    @Test
     public void testWithCustomSchemaFromProperties() throws Exception
     {
         Properties props = new Properties();
@@ -63,6 +70,7 @@ public void testWithCustomSchemaFromProperties() throws Exception
     }
 
     // for [dataformats-text#139]
+    @Test
     public void testWithCustomSchemaFromMap() throws Exception
     {
         Map<String, String> map = new LinkedHashMap<>();
@@ -95,6 +103,7 @@ private void _verifyCustom(Map<?,?> result)
     }
 
     // [dataformats-text#91]
+    @Test
     public void testEscapingWithReadPropertiesAs() throws Exception
     {
         TestObject91 expected = new TestObject91();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SchemaConstructionTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SchemaConstructionTest.java
index c1883e394..d9d04030c 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SchemaConstructionTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SchemaConstructionTest.java
@@ -1,8 +1,14 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
 public class SchemaConstructionTest extends ModuleTestBase
 {
     // Tests to verify stickiness of settings
+    @Test
     public void testMutantFactories()
     {
         JavaPropsSchema empty = JavaPropsSchema.emptySchema();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleGenerationTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleGenerationTest.java
index 78b4f2a73..4311dd621 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleGenerationTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleGenerationTest.java
@@ -3,10 +3,16 @@
 import java.util.Map;
 import java.util.Properties;
 
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+
 public class SimpleGenerationTest extends ModuleTestBase
 {
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testSimpleEmployee() throws Exception
     {
         FiveMinuteUser input = new FiveMinuteUser("Bob", "Palmer", true, Gender.MALE,
@@ -32,6 +38,7 @@ public void testSimpleEmployee() throws Exception
         }
     }
 
+    @Test
     public void testSimpleRectangle() throws Exception
     {
         Rectangle input = new Rectangle(new Point(1, -2), new Point(5, 10));
@@ -53,6 +60,7 @@ public void testSimpleRectangle() throws Exception
         }
     }
 
+    @Test
     public void testRectangleWithCustomKeyValueSeparator() throws Exception
     {
         JavaPropsSchema schema = JavaPropsSchema.emptySchema()
@@ -76,6 +84,7 @@ public void testRectangleWithCustomKeyValueSeparator() throws Exception
         }
     }
 
+    @Test
     public void testRectangleWithHeader() throws Exception
     {
         final String HEADER = "# SUPER IMPORTANT!\n";
@@ -92,6 +101,7 @@ public void testRectangleWithHeader() throws Exception
                 ,output);
     }
 
+    @Test
     public void testRectangleWithIndent() throws Exception
     {
         JavaPropsSchema schema = JavaPropsSchema.emptySchema()
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleParsingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleParsingTest.java
index a85235d51..0f395e9f2 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleParsingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleParsingTest.java
@@ -2,30 +2,38 @@
 
 import java.util.Map;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.json.JsonMapper;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 public class SimpleParsingTest extends ModuleTestBase
 {
     private final ObjectMapper MAPPER = newPropertiesMapper();
 
     private final ObjectMapper JSON_MAPPER = new JsonMapper();
 
+    @Test
     public void testSimpleNonNested() throws Exception {
         _testSimpleNonNested(false);
         _testSimpleNonNested(true);
     }
 
+    @Test
     public void testSimpleNested() throws Exception {
         _testSimpleNested(false);
         _testSimpleNested(true);
     }
 
+    @Test
     public void testSimpleRectangle() throws Exception {
         _testSimpleRectangle(false);
         _testSimpleRectangle(true);
     }
 
+    @Test
     public void testNonSplittingParsing() throws Exception {
         JavaPropsSchema schema = JavaPropsSchema.emptySchema()
                 .withoutPathSeparator();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleStreamingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleStreamingTest.java
index 558d3154f..7e5f3e4f6 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleStreamingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/SimpleStreamingTest.java
@@ -1,27 +1,26 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import java.io.Reader;
-import java.io.StringWriter;
-import java.io.Writer;
+import java.io.*;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.util.Map;
 
-import com.fasterxml.jackson.core.JsonGenerator;
-import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.core.JsonProcessingException;
-import com.fasterxml.jackson.core.JsonStreamContext;
-import com.fasterxml.jackson.core.JsonToken;
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.io.SerializedString;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.dataformat.javaprop.io.JPropWriteContext;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 public class SimpleStreamingTest extends ModuleTestBase
 {
     private final ObjectMapper MAPPER = newPropertiesMapper();
 
     private final JavaPropsFactory F = new JavaPropsFactory();
 
+    @Test
     public void testParsing() throws Exception
     {
         JsonParser p = F.createParser("foo = bar");
@@ -62,6 +61,7 @@ public void testParsing() throws Exception
         p.close();
     }
 
+    @Test
     public void testStreamingGeneration() throws Exception
     {
         StringWriter strw = new StringWriter();
@@ -110,6 +110,7 @@ public void testStreamingGeneration() throws Exception
         assertEquals("10", stuff.get("long"));
     }
 
+    @Test
     public void testStreamingGenerationRaw() throws Exception
     {
         StringWriter strw = new StringWriter();
@@ -137,6 +138,7 @@ public void testStreamingGenerationRaw() throws Exception
         assertEquals("true", stuff.get("enabled"));
     }        
 
+    @Test
     public void testStreamingLongRaw() throws Exception
     {
         StringWriter strw = new StringWriter();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/StreamClosingTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/StreamClosingTest.java
index fd4a4f529..eea352b7a 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/StreamClosingTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/StreamClosingTest.java
@@ -1,10 +1,14 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.dataformat.javaprop.testutil.CloseStateInputStream;
 import com.fasterxml.jackson.dataformat.javaprop.testutil.CloseStateReader;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 @SuppressWarnings("resource")
 public class StreamClosingTest extends ModuleTestBase
 {
@@ -17,6 +21,7 @@ public static class Bean179 {
 
     private final ObjectMapper PROPS_MAPPER = newPropertiesMapper();
 
+    @Test
     public void testInputStreamClosing() throws Exception
     {
         // by default, SHOULD close it:
@@ -36,6 +41,7 @@ public void testInputStreamClosing() throws Exception
         assertTrue(in.closed);
     }
 
+    @Test
     public void testReaderClosing() throws Exception
     {
         // by default, SHOULD close it:
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/TestVersions.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/TestVersions.java
index f3e204455..ad024e086 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/TestVersions.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/TestVersions.java
@@ -1,11 +1,19 @@
 package com.fasterxml.jackson.dataformat.javaprop;
 
-import java.io.*;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 
-import com.fasterxml.jackson.core.*;
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.Versioned;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 public class TestVersions extends ModuleTestBase
 {
+    @Test
     public void testMapperVersions() throws IOException
     {
         JavaPropsFactory f = new JavaPropsFactory();
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/constraints/DeeplyNestedPropsReadWriteTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/constraints/DeeplyNestedPropsReadWriteTest.java
index 1e2916850..2fe42e9f4 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/constraints/DeeplyNestedPropsReadWriteTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/constraints/DeeplyNestedPropsReadWriteTest.java
@@ -1,15 +1,15 @@
 package com.fasterxml.jackson.dataformat.javaprop.constraints;
 
-import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.core.StreamReadConstraints;
-import com.fasterxml.jackson.core.StreamWriteConstraints;
+import org.junit.jupiter.api.Test;
+
+import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.core.exc.StreamConstraintsException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ObjectNode;
-import com.fasterxml.jackson.dataformat.javaprop.JavaPropsFactory;
-import com.fasterxml.jackson.dataformat.javaprop.JavaPropsMapper;
-import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
+import com.fasterxml.jackson.dataformat.javaprop.*;
+
+import static org.junit.jupiter.api.Assertions.*;
 
 public class DeeplyNestedPropsReadWriteTest extends ModuleTestBase
 {
@@ -25,6 +25,7 @@ public class DeeplyNestedPropsReadWriteTest extends ModuleTestBase
             .build()
             );
 
+    @Test
     public void testDeepNestingRead() throws Exception
     {
         final String DOC = PROPS_MAPPER_CONSTR.writeValueAsString(createDeepNestedDoc(11));
@@ -44,6 +45,7 @@ private void _testDeepNestingRead(JsonParser p) throws Exception
         }
     }
     
+    @Test
     public void testDeepNestingWrite() throws Exception
     {
         final JsonNode docRoot = createDeepNestedDoc(13);
@@ -56,6 +58,7 @@ public void testDeepNestingWrite() throws Exception
         }
     }
     
+    @Test
     public void testDeeplyNestedReadVanilla() throws Exception {
         final int depth = 1500;
         final String doc = createDeepNestedString(depth);
@@ -65,11 +68,12 @@ public void testDeeplyNestedReadVanilla() throws Exception {
         } catch (StreamConstraintsException e) {
             String exceptionPrefix = String.format("Document nesting depth (%d) exceeds the maximum allowed",
                     StreamReadConstraints.DEFAULT_MAX_DEPTH + 1);
-            assertTrue("unexpected exception message: " + e.getMessage(),
-                    e.getMessage().startsWith(exceptionPrefix));
+            assertTrue(e.getMessage().startsWith(exceptionPrefix),
+                    "unexpected exception message: " + e.getMessage());
         }
     }
 
+    @Test
     public void testDeeplyNestedReadWithUnconstrainedMapper() throws Exception {
         final int depth = 1500;
         final String doc = createDeepNestedString(depth);
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/FuzzPropsReadTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/FuzzPropsReadTest.java
index 2322ade1c..cbe51f23a 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/FuzzPropsReadTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/FuzzPropsReadTest.java
@@ -2,17 +2,22 @@
 
 import java.io.IOException;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
-
 import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
 // Tests for things found via https://oss-fuzz.com/
 public class FuzzPropsReadTest extends ModuleTestBase
 {
     private final ObjectMapper MAPPER = newPropertiesMapper();
 
     // https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=50053
+    @Test
     public void testInvalidUnicodeEscape50053() throws Exception
     {
         String INPUT = "\\u";
@@ -26,6 +31,7 @@ public void testInvalidUnicodeEscape50053() throws Exception
     }
 
     // https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=51247
+    @Test
     public void testDoubleSeparators51247() throws Exception
     {
         // Threw IndexOutOfBoundsException since counter was not cleared
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/CoerceToBooleanTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/CoerceToBooleanTest.java
index 2c16d448d..1a0fd8bc0 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/CoerceToBooleanTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/CoerceToBooleanTest.java
@@ -3,12 +3,16 @@
 import java.io.IOException;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.cfg.CoercionAction;
 import com.fasterxml.jackson.databind.cfg.CoercionInputShape;
 import com.fasterxml.jackson.databind.type.LogicalType;
 import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 // 2020-12-18, tatu: Modified from "jackson-databind" version: Properties
 //   backend MUST NOT prevent coercion from String since Properties
 //   values are fundamentally textual and only have String values
@@ -56,6 +60,7 @@ static class AtomicBooleanWrapper {
      */
 
     // for [databind#403]
+    @Test
     public void testEmptyStringFailForBooleanPrimitive() throws IOException
     {
         final ObjectReader reader = MAPPER_EMPTY_TO_BOOLEAN_FAIL
@@ -69,6 +74,7 @@ public void testEmptyStringFailForBooleanPrimitive() throws IOException
         }
     }
 
+    @Test
     public void testDefaultStringToBooleanCoercionOk() throws Exception {
         _verifyStringToBooleanOk(DEFAULT_MAPPER);
     }
@@ -79,6 +85,7 @@ public void testDefaultStringToBooleanCoercionOk() throws Exception {
     /**********************************************************
      */
 
+    @Test
     public void testStringToBooleanOkDespiteCoercionConfig() throws Exception {
         _verifyStringToBooleanOk(MAPPER_STRING_TO_BOOLEAN_FAIL);
     }
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/DefaultFromEmptyCoercionsTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/DefaultFromEmptyCoercionsTest.java
index 758862bf6..957f23c6b 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/DefaultFromEmptyCoercionsTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/deser/convert/DefaultFromEmptyCoercionsTest.java
@@ -1,13 +1,15 @@
 package com.fasterxml.jackson.dataformat.javaprop.deser.convert;
 
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
+
+import org.junit.jupiter.api.Test;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.ObjectReader;
 import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 // 09-Apr-2021, tatu: Since Properties format has very loose typing
 //   many coercions are needed and are enabled by default. Let's
 //   verify that "from Empty String" cases work for a full set of
@@ -48,6 +50,7 @@ static class SomeContainers {
     /**********************************************************************
      */
     
+    @Test
     public void testJDKPrimitives() throws Exception
     {
         SomePrimitives p;
@@ -69,6 +72,7 @@ public void testJDKPrimitives() throws Exception
         assertEquals((double) 0, p.d);
     }
 
+    @Test
     public void testJDKWrappers() throws Exception {
         SomeWrappers w;
         final ObjectReader r = DEFAULT_MAPPER.readerFor(SomeWrappers.class);
@@ -92,6 +96,7 @@ public void testJDKWrappers() throws Exception {
         assertEquals(Double.valueOf(0), w.d);
     }
 
+    @Test
     public void testJDKStringTypes() throws Exception
     {
         StringBean v;
@@ -105,6 +110,7 @@ public void testJDKStringTypes() throws Exception
         assertEquals("", v.str);
     }
 
+    @Test
     public void testJDKContainerTypes() throws Exception {
         SomeContainers w;
         final ObjectReader r = DEFAULT_MAPPER.readerFor(SomeContainers.class);
@@ -140,6 +146,7 @@ public void testJDKContainerTypes() throws Exception {
     /**********************************************************************
      */
 
+    @Test
     public void testPOJOs() throws Exception
     {
         final ObjectReader r = DEFAULT_MAPPER.readerFor(Rectangle.class);
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/dos/CyclicPropsDataSerTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/dos/CyclicPropsDataSerTest.java
index 68211eba2..b79192699 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/dos/CyclicPropsDataSerTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/dos/CyclicPropsDataSerTest.java
@@ -3,12 +3,17 @@
 import java.util.ArrayList;
 import java.util.List;
 
-import com.fasterxml.jackson.core.StreamWriteConstraints;
+import org.junit.jupiter.api.Test;
 
+import com.fasterxml.jackson.core.StreamWriteConstraints;
 import com.fasterxml.jackson.databind.DatabindException;
 import com.fasterxml.jackson.dataformat.javaprop.JavaPropsMapper;
 import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
 
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.fail;
+
+
 /**
  * Simple unit tests to verify that we fail gracefully if you attempt to serialize
  * data that is cyclic (eg a list that contains itself).
@@ -17,6 +22,7 @@ public class CyclicPropsDataSerTest extends ModuleTestBase
 {
     private final JavaPropsMapper MAPPER = newPropertiesMapper();
 
+    @Test
     public void testListWithSelfReference() throws Exception {
         List<Object> list = new ArrayList<>();
         list.add(list);
@@ -26,8 +32,9 @@ public void testListWithSelfReference() throws Exception {
         } catch (DatabindException e) {
             String exceptionPrefix = String.format("Document nesting depth (%d) exceeds the maximum allowed",
                     StreamWriteConstraints.DEFAULT_MAX_DEPTH + 1);
-            assertTrue("JsonMappingException message is as expected?",
-                    e.getMessage().startsWith(exceptionPrefix));
+            assertTrue(e.getMessage().startsWith(exceptionPrefix),
+                    "JsonMapping" +
+                                        "Exception message is as expected?");
         }
     }
 }
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/filter/StreamingDecoratorsTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/filter/StreamingDecoratorsTest.java
index 8ecc0aa72..db991aa89 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/filter/StreamingDecoratorsTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/filter/StreamingDecoratorsTest.java
@@ -1,17 +1,23 @@
 package com.fasterxml.jackson.dataformat.javaprop.filter;
 
 import java.io.*;
-import java.util.*;
+import java.util.LinkedHashMap;
+import java.util.Map;
 
-import com.fasterxml.jackson.databind.*;
+import org.junit.jupiter.api.Test;
 
-import com.fasterxml.jackson.dataformat.javaprop.*;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
 import com.fasterxml.jackson.dataformat.javaprop.testutil.PrefixInputDecorator;
 import com.fasterxml.jackson.dataformat.javaprop.testutil.PrefixOutputDecorator;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+
 public class StreamingDecoratorsTest extends ModuleTestBase
 {
     @SuppressWarnings("unchecked")
+    @Test
     public void testInputDecorators() throws IOException
     {
         final byte[] DOC = utf8("secret=mum\n");
@@ -32,6 +38,7 @@ public void testInputDecorators() throws IOException
     }
 
     @SuppressWarnings("unchecked")
+    @Test
     public void testOutputDecorators() throws IOException
     {
         final byte[] DOC = utf8("prefix=p\n");
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/CloseStateInputStream.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/CloseStateInputStream.java
index 11bc6dffd..d57b86d2c 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/CloseStateInputStream.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/CloseStateInputStream.java
@@ -1,9 +1,6 @@
 package com.fasterxml.jackson.dataformat.javaprop.testutil;
 
-import java.io.ByteArrayInputStream;
-import java.io.FilterInputStream;
-import java.io.IOException;
-import java.io.InputStream;
+import java.io.*;
 
 public class CloseStateInputStream extends FilterInputStream
 {
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixInputDecorator.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixInputDecorator.java
index 78e6a675e..8d2d9185f 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixInputDecorator.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixInputDecorator.java
@@ -1,11 +1,6 @@
 package com.fasterxml.jackson.dataformat.javaprop.testutil;
 
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.Reader;
-import java.io.SequenceInputStream;
-import java.io.StringReader;
+import java.io.*;
 import java.nio.charset.StandardCharsets;
 
 import com.fasterxml.jackson.core.io.IOContext;
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixOutputDecorator.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixOutputDecorator.java
index 032cca30c..3cb2c2841 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixOutputDecorator.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/testutil/PrefixOutputDecorator.java
@@ -1,9 +1,6 @@
 package com.fasterxml.jackson.dataformat.javaprop.testutil;
 
-import java.io.FilterOutputStream;
-import java.io.IOException;
-import java.io.OutputStream;
-import java.io.Writer;
+import java.io.*;
 
 import com.fasterxml.jackson.core.io.IOContext;
 import com.fasterxml.jackson.core.io.OutputDecorator;
diff --git a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropPathSplitterTest.java b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropPathSplitterTest.java
index 97a489438..672e443f5 100644
--- a/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropPathSplitterTest.java
+++ b/properties/src/test/java/com/fasterxml/jackson/dataformat/javaprop/util/JPropPathSplitterTest.java
@@ -1,10 +1,15 @@
 package com.fasterxml.jackson.dataformat.javaprop.util;
 
+import org.junit.jupiter.api.Test;
+
 import com.fasterxml.jackson.dataformat.javaprop.JavaPropsSchema;
 import com.fasterxml.jackson.dataformat.javaprop.ModuleTestBase;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 public class JPropPathSplitterTest extends ModuleTestBase
 {
+    @Test
     public void testSplitters()
     {
         JPropPathSplitter sp = JPropPathSplitter.create(JavaPropsSchema.emptySchema());