diff --git a/core/tests/coretests/src/android/view/textclassifier/ActionsSuggestionsHelperTest.java b/core/tests/coretests/src/android/view/textclassifier/ActionsSuggestionsHelperTest.java
index 80bce264c11b4..ec7e83f1f2439 100644
--- a/core/tests/coretests/src/android/view/textclassifier/ActionsSuggestionsHelperTest.java
+++ b/core/tests/coretests/src/android/view/textclassifier/ActionsSuggestionsHelperTest.java
@@ -238,6 +238,7 @@ public class ActionsSuggestionsHelperTest {
         assertThat(conversationActions).isEmpty();
     }
 
+    @Test
     public void createLabeledIntentResult_null() {
         ActionsSuggestionsModel.ActionSuggestion nativeSuggestion =
                 new ActionsSuggestionsModel.ActionSuggestion(
diff --git a/core/tests/systemproperties/src/android/os/SystemPropertiesTest.java b/core/tests/systemproperties/src/android/os/SystemPropertiesTest.java
index 9f70538191c20..67783bff92994 100644
--- a/core/tests/systemproperties/src/android/os/SystemPropertiesTest.java
+++ b/core/tests/systemproperties/src/android/os/SystemPropertiesTest.java
@@ -94,7 +94,7 @@ public class SystemPropertiesTest extends TestCase {
     }
 
     @SmallTest
-    private static void testHandle() throws Exception {
+    public void testHandle() throws Exception {
         String value;
         SystemProperties.Handle handle = SystemProperties.find("doesnotexist_2341431");
         assertNull(handle);
diff --git a/services/tests/servicestests/src/com/android/server/backup/utils/FileUtilsTest.java b/services/tests/servicestests/src/com/android/server/backup/utils/FileUtilsTest.java
index eaa9c45209795..d54aa3b1c2f65 100644
--- a/services/tests/servicestests/src/com/android/server/backup/utils/FileUtilsTest.java
+++ b/services/tests/servicestests/src/com/android/server/backup/utils/FileUtilsTest.java
@@ -27,7 +27,6 @@ import com.google.common.io.Files;
 
 import org.junit.AfterClass;
 import org.junit.Before;
-import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -41,11 +40,6 @@ public class FileUtilsTest {
     private static File sTemporaryDir;
     private File mTemporaryFile;
 
-    @BeforeClass
-    public static void setUpClass() {
-        sTemporaryDir = Files.createTempDir();
-    }
-
     @AfterClass
     public static void tearDownClass() {
         if (sTemporaryDir != null) {
@@ -55,17 +49,21 @@ public class FileUtilsTest {
 
     @Before
     public void setUp() throws Exception {
+        if (sTemporaryDir != null) {
+            sTemporaryDir.delete();
+        }
+        sTemporaryDir = Files.createTempDir();
         mTemporaryFile = new File(sTemporaryDir, "fileutilstest.txt");
     }
 
     /** Test that if file does not exist, {@link FileUtils#createNewFile()} creates the file. */
     @Test
     public void testEnsureFileExists_fileDoesNotAlreadyExist_getsCreated() {
-        assertThat(!mTemporaryFile.exists());
+        assertThat(mTemporaryFile.exists()).isFalse();
 
         FileUtils.createNewFile(mTemporaryFile);
 
-        assertThat(mTemporaryFile.exists());
+        assertThat(mTemporaryFile.exists()).isTrue();
     }
 
     /** Test that if file does exist, {@link FileUtils#createNewFile()} does not error out. */
@@ -75,6 +73,6 @@ public class FileUtilsTest {
 
         FileUtils.createNewFile(mTemporaryFile);
 
-        assertThat(mTemporaryFile.exists());
+        assertThat(mTemporaryFile.exists()).isTrue();
     }
 }
diff --git a/services/tests/servicestests/src/com/android/server/hdmi/HdmiCecLocalDeviceAudioSystemTest.java b/services/tests/servicestests/src/com/android/server/hdmi/HdmiCecLocalDeviceAudioSystemTest.java
index a89198ae37083..163832983b5b7 100644
--- a/services/tests/servicestests/src/com/android/server/hdmi/HdmiCecLocalDeviceAudioSystemTest.java
+++ b/services/tests/servicestests/src/com/android/server/hdmi/HdmiCecLocalDeviceAudioSystemTest.java
@@ -530,6 +530,7 @@ public class HdmiCecLocalDeviceAudioSystemTest {
         assertThat(mNativeWrapper.getOnlyResultMessage()).isEqualTo(expectedMessage);
     }
 
+    @Test
     public void handleSystemAudioModeRequest_fromNonTV_tVNotSupport() {
         HdmiCecMessage message =
                 HdmiCecMessageBuilder.buildSystemAudioModeRequest(
diff --git a/services/tests/servicestests/src/com/android/server/locksettings/LockSettingsStorageTests.java b/services/tests/servicestests/src/com/android/server/locksettings/LockSettingsStorageTests.java
index a1f423e77865a..ab9b39c280e9d 100644
--- a/services/tests/servicestests/src/com/android/server/locksettings/LockSettingsStorageTests.java
+++ b/services/tests/servicestests/src/com/android/server/locksettings/LockSettingsStorageTests.java
@@ -477,6 +477,7 @@ public class LockSettingsStorageTests {
         assertEquals(2, PersistentData.TYPE_SP_WEAVER);
     }
 
+    @Test
     public void testCredentialHash_serializeUnserialize() {
         byte[] serialized = CredentialHash.create(
                 PAYLOAD, LockPatternUtils.CREDENTIAL_TYPE_PASSWORD).toBytes();
@@ -488,6 +489,7 @@ public class LockSettingsStorageTests {
         assertFalse(deserialized.isBaseZeroPattern);
     }
 
+    @Test
     public void testCredentialHash_unserialize_versionGatekeeper() {
         // This test ensures that we can read serialized VERSION_GATEKEEPER CredentialHashes
         // even if we change the wire format in the future.
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
index b5542afed46d4..0fce618012f95 100755
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
@@ -4193,6 +4193,7 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
         assertEquals(0, mService.countLogSmartSuggestionsVisible);
     }
 
+    @Test
     public void testReportSeen_delegated() {
         Notification.Builder nb =
                 new Notification.Builder(mContext, mTestNotificationChannel.getId())