Port tests from JUnit 3 to JUnit 4

extras/src/test/java/com/google/gson/interceptors/InterceptorTest.java

@@ -15,6 +15,9 @@
  */
 package com.google.gson.interceptors;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonParseException;
@@ -29,50 +32,55 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
-import junit.framework.TestCase;
+import org.junit.Before;
+import org.junit.Test;
 
 /**
  * Unit tests for {@link Intercept} and {@link JsonPostDeserializer}.
  *
  * @author Inderjeet Singh
  */
-public final class InterceptorTest extends TestCase {
+public final class InterceptorTest {
 
   private Gson gson;
 
-  @Override
+  @Before
   public void setUp() throws Exception {
-    super.setUp();
     this.gson = new GsonBuilder()
         .registerTypeAdapterFactory(new InterceptorFactory())
         .enableComplexMapKeySerialization()
         .create();
   }
 
+  @Test
   public void testExceptionsPropagated() {
     try {
       gson.fromJson("{}", User.class);
       fail();
     } catch (JsonParseException expected) {}
   }
 
+  @Test
   public void testTopLevelClass() {
     User user = gson.fromJson("{name:'bob',password:'pwd'}", User.class);
     assertEquals(User.DEFAULT_EMAIL, user.email);
   }
 
+  @Test
   public void testList() {
     List<User> list = gson.fromJson("[{name:'bob',password:'pwd'}]", new TypeToken<List<User>>(){}.getType());
     User user = list.get(0);
     assertEquals(User.DEFAULT_EMAIL, user.email);
   }
 
+  @Test
   public void testCollection() {
     Collection<User> list = gson.fromJson("[{name:'bob',password:'pwd'}]", new TypeToken<Collection<User>>(){}.getType());
     User user = list.iterator().next();
     assertEquals(User.DEFAULT_EMAIL, user.email);
   }
 
+  @Test
   public void testMapKeyAndValues() {
     Type mapType = new TypeToken<Map<User, Address>>(){}.getType();
     try {
@@ -86,11 +94,13 @@ public void testMapKeyAndValues() {
     assertEquals(Address.DEFAULT_FIRST_LINE, entry.getValue().firstLine);
   }
 
+  @Test
   public void testField() {
     UserGroup userGroup = gson.fromJson("{user:{name:'bob',password:'pwd'}}", UserGroup.class);
     assertEquals(User.DEFAULT_EMAIL, userGroup.user.email);
   }
 
+  @Test
   public void testCustomTypeAdapter() {
     Gson gson = new GsonBuilder()
         .registerTypeAdapter(User.class, new TypeAdapter<User>() {
@@ -114,6 +124,7 @@ public void testCustomTypeAdapter() {
     assertEquals(User.DEFAULT_EMAIL, userGroup.user.email);
   }
 
+  @Test
   public void testDirectInvocationOfTypeAdapter() throws Exception {
     TypeAdapter<UserGroup> adapter = gson.getAdapter(UserGroup.class);
     UserGroup userGroup = adapter.fromJson("{\"user\":{\"name\":\"bob\",\"password\":\"pwd\"}}");

extras/src/test/java/com/google/gson/typeadapters/PostConstructAdapterFactoryTest.java

@@ -16,15 +16,19 @@
 
 package com.google.gson.typeadapters;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import java.util.Arrays;
 import java.util.List;
 import javax.annotation.PostConstruct;
-import junit.framework.TestCase;
+import org.junit.Test;
 
-public class PostConstructAdapterFactoryTest extends TestCase {
-    public void test() throws Exception {
+public class PostConstructAdapterFactoryTest {
+  @Test
+  public void test() throws Exception {
         Gson gson = new GsonBuilder()
                 .registerTypeAdapterFactory(new PostConstructAdapterFactory())
                 .create();
@@ -37,7 +41,8 @@ public void test() throws Exception {
         }
     }
 
-    public void testList() {
+  @Test
+  public void testList() {
         MultipleSandwiches sandwiches = new MultipleSandwiches(Arrays.asList(
             new Sandwich("white", "cheddar"),
             new Sandwich("whole wheat", "swiss")));

extras/src/test/java/com/google/gson/typeadapters/RuntimeTypeAdapterFactoryTest.java

@@ -16,14 +16,20 @@
 
 package com.google.gson.typeadapters;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonParseException;
 import com.google.gson.TypeAdapterFactory;
-import junit.framework.TestCase;
+import org.junit.Test;
 
-public final class RuntimeTypeAdapterFactoryTest extends TestCase {
+public final class RuntimeTypeAdapterFactoryTest {
 
+  @Test
   public void testRuntimeTypeAdapter() {
     RuntimeTypeAdapterFactory<BillingInstrument> rta = RuntimeTypeAdapterFactory.of(
         BillingInstrument.class)
@@ -41,6 +47,7 @@ public void testRuntimeTypeAdapter() {
     assertTrue(deserialized instanceof CreditCard);
   }
 
+  @Test
   public void testRuntimeTypeAdapterRecognizeSubtypes() {
     // We don't have an explicit factory for CreditCard.class, but we do have one for
     // BillingInstrument.class that has recognizeSubtypes(). So it should recognize CreditCard, and
@@ -62,6 +69,7 @@ public void testRuntimeTypeAdapterRecognizeSubtypes() {
     assertTrue(deserialized instanceof CreditCard);
   }
 
+  @Test
   public void testRuntimeTypeIsBaseType() {
     TypeAdapterFactory rta = RuntimeTypeAdapterFactory.of(
         BillingInstrument.class)
@@ -78,6 +86,7 @@ public void testRuntimeTypeIsBaseType() {
     assertEquals("Jesse", deserialized.ownerName);
   }
 
+  @Test
   public void testNullBaseType() {
     try {
       RuntimeTypeAdapterFactory.of(null);
@@ -86,6 +95,7 @@ public void testNullBaseType() {
     }
   }
 
+  @Test
   public void testNullTypeFieldName() {
     try {
       RuntimeTypeAdapterFactory.of(BillingInstrument.class, null);
@@ -94,6 +104,7 @@ public void testNullTypeFieldName() {
     }
   }
 
+  @Test
   public void testNullSubtype() {
     RuntimeTypeAdapterFactory<BillingInstrument> rta = RuntimeTypeAdapterFactory.of(
         BillingInstrument.class);
@@ -104,6 +115,7 @@ public void testNullSubtype() {
     }
   }
 
+  @Test
   public void testNullLabel() {
     RuntimeTypeAdapterFactory<BillingInstrument> rta = RuntimeTypeAdapterFactory.of(
         BillingInstrument.class);
@@ -114,6 +126,7 @@ public void testNullLabel() {
     }
   }
 
+  @Test
   public void testDuplicateSubtype() {
     RuntimeTypeAdapterFactory<BillingInstrument> rta = RuntimeTypeAdapterFactory.of(
         BillingInstrument.class);
@@ -125,6 +138,7 @@ public void testDuplicateSubtype() {
     }
   }
 
+  @Test
   public void testDuplicateLabel() {
     RuntimeTypeAdapterFactory<BillingInstrument> rta = RuntimeTypeAdapterFactory.of(
         BillingInstrument.class);
@@ -136,6 +150,7 @@ public void testDuplicateLabel() {
     }
   }
 
+  @Test
   public void testDeserializeMissingTypeField() {
     TypeAdapterFactory billingAdapter = RuntimeTypeAdapterFactory.of(BillingInstrument.class)
         .registerSubtype(CreditCard.class);
@@ -149,6 +164,7 @@ public void testDeserializeMissingTypeField() {
     }
   }
 
+  @Test
   public void testDeserializeMissingSubtype() {
     TypeAdapterFactory billingAdapter = RuntimeTypeAdapterFactory.of(BillingInstrument.class)
         .registerSubtype(BankTransfer.class);
@@ -162,6 +178,7 @@ public void testDeserializeMissingSubtype() {
     }
   }
 
+  @Test
   public void testSerializeMissingSubtype() {
     TypeAdapterFactory billingAdapter = RuntimeTypeAdapterFactory.of(BillingInstrument.class)
         .registerSubtype(BankTransfer.class);
@@ -175,6 +192,7 @@ public void testSerializeMissingSubtype() {
     }
   }
 
+  @Test
   public void testSerializeCollidingTypeFieldName() {
     TypeAdapterFactory billingAdapter = RuntimeTypeAdapterFactory.of(BillingInstrument.class, "cvv")
         .registerSubtype(CreditCard.class);
@@ -188,6 +206,7 @@ public void testSerializeCollidingTypeFieldName() {
     }
   }
 
+  @Test
   public void testSerializeWrappedNullValue() {
     TypeAdapterFactory billingAdapter = RuntimeTypeAdapterFactory.of(BillingInstrument.class)
         .registerSubtype(CreditCard.class)

extras/src/test/java/com/google/gson/typeadapters/UtcDateTypeAdapterTest.java

@@ -16,6 +16,9 @@
 
 package com.google.gson.typeadapters;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonParseException;
@@ -24,20 +27,22 @@
 import java.util.Date;
 import java.util.Locale;
 import java.util.TimeZone;
-import junit.framework.TestCase;
+import org.junit.Test;
 
-public final class UtcDateTypeAdapterTest extends TestCase {
+public final class UtcDateTypeAdapterTest {
   private final Gson gson = new GsonBuilder()
     .registerTypeAdapter(Date.class, new UtcDateTypeAdapter())
     .create();
 
+  @Test
   public void testLocalTimeZone() {
     Date expected = new Date();
     String json = gson.toJson(expected);
     Date actual = gson.fromJson(json, Date.class);
     assertEquals(expected.getTime(), actual.getTime());
   }
 
+  @Test
   public void testDifferentTimeZones() {
     for (String timeZone : TimeZone.getAvailableIDs()) {
       Calendar cal = Calendar.getInstance(TimeZone.getTimeZone(timeZone));
@@ -53,13 +58,15 @@ public void testDifferentTimeZones() {
    * JDK 1.7 introduced support for XXX format to indicate UTC date. But Android is older JDK.
    * We want to make sure that this date is parseable in Android.
    */
+  @Test
   public void testUtcDatesOnJdkBefore1_7() {
     Gson gson = new GsonBuilder()
       .registerTypeAdapter(Date.class, new UtcDateTypeAdapter())
       .create();
     gson.fromJson("'2014-12-05T04:00:00.000Z'", Date.class);
   }
 
+  @Test
   public void testUtcWithJdk7Default() {
     Date expected = new Date();
     SimpleDateFormat iso8601Format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSXXX", Locale.US);
@@ -71,11 +78,13 @@ public void testUtcWithJdk7Default() {
     assertEquals(expected.getTime(), actual.getTime());
   }
 
+  @Test
   public void testNullDateSerialization() {
     String json = gson.toJson(null, Date.class);
     assertEquals("null", json);
   }
 
+  @Test
   public void testWellFormedParseException() {
     try {
       gson.fromJson("2017-06-20T14:32:30", Date.class);

gson/src/test/java/com/google/gson/CommentsTest.java

@@ -16,19 +16,22 @@
 
 package com.google.gson;
 
+import static org.junit.Assert.assertEquals;
+
 import com.google.gson.reflect.TypeToken;
 import java.util.Arrays;
 import java.util.List;
-import junit.framework.TestCase;
+import org.junit.Test;
 
 /**
  * @author Jesse Wilson
  */
-public final class CommentsTest extends TestCase {
+public final class CommentsTest {
 
   /**
    * Test for issue 212.
    */
+  @Test
   public void testParseComments() {
     String json = "[\n"
         + "  // this is a comment\n"

gson/src/test/java/com/google/gson/DefaultInetAddressTypeAdapterTest.java

@@ -16,24 +16,26 @@
 
 package com.google.gson;
 
-import java.net.InetAddress;
+import static org.junit.Assert.assertEquals;
 
-import junit.framework.TestCase;
+import java.net.InetAddress;
+import org.junit.Before;
+import org.junit.Test;
 
 /**
  * Unit tests for the default serializer/deserializer for the {@code InetAddress} type.
  * 
  * @author Joel Leitch
  */
-public class DefaultInetAddressTypeAdapterTest extends TestCase {
+public class DefaultInetAddressTypeAdapterTest {
   private Gson gson;
 
-  @Override
-  protected void setUp() throws Exception {
-    super.setUp();
+  @Before
+  public void setUp() throws Exception {
     gson = new Gson();
   }
 
+  @Test
   public void testInetAddressSerializationAndDeserialization() throws Exception {
     InetAddress address = InetAddress.getByName("8.8.8.8");
     String jsonAddress = gson.toJson(address);