diff --git a/wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/CommandGroupBase.java b/wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/CommandGroupBase.java
index e360980887..d3a35d4004 100644
--- a/wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/CommandGroupBase.java
+++ b/wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/CommandGroupBase.java
@@ -14,7 +14,7 @@ import java.util.WeakHashMap;
  * those commands are not also used independently, which can result in inconsistent command state
  * and unpredictable execution.
  */
-public abstract class CommandGroupBase extends CommandBase implements Command {
+public abstract class CommandGroupBase extends CommandBase {
   private static final Set<Command> m_groupedCommands =
       Collections.newSetFromMap(new WeakHashMap<>());
 
diff --git a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Command.java b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Command.java
index d03bf01e0e..5bb49a3800 100644
--- a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Command.java
+++ b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Command.java
@@ -353,7 +353,7 @@ public abstract class Command implements Sendable, AutoCloseable {
    * @return the requirements (as an {@link Enumeration Enumeration} of {@link Subsystem
    *     Subsystems}) of this command
    */
-  synchronized Enumeration getRequirements() {
+  synchronized Enumeration<?> getRequirements() {
     return m_requirements.getElements();
   }
 
diff --git a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/CommandGroup.java b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/CommandGroup.java
index ebdd1f8d18..5a4294a81a 100644
--- a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/CommandGroup.java
+++ b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/CommandGroup.java
@@ -81,7 +81,7 @@ public class CommandGroup extends Command {
     command.setParent(this);
 
     m_commands.addElement(new Entry(command, Entry.IN_SEQUENCE));
-    for (Enumeration e = command.getRequirements(); e.hasMoreElements(); ) {
+    for (Enumeration<?> e = command.getRequirements(); e.hasMoreElements(); ) {
       requires((Subsystem) e.nextElement());
     }
   }
@@ -119,7 +119,7 @@ public class CommandGroup extends Command {
     command.setParent(this);
 
     m_commands.addElement(new Entry(command, Entry.IN_SEQUENCE, timeout));
-    for (Enumeration e = command.getRequirements(); e.hasMoreElements(); ) {
+    for (Enumeration<?> e = command.getRequirements(); e.hasMoreElements(); ) {
       requires((Subsystem) e.nextElement());
     }
   }
@@ -152,7 +152,7 @@ public class CommandGroup extends Command {
     command.setParent(this);
 
     m_commands.addElement(new Entry(command, Entry.BRANCH_CHILD));
-    for (Enumeration e = command.getRequirements(); e.hasMoreElements(); ) {
+    for (Enumeration<?> e = command.getRequirements(); e.hasMoreElements(); ) {
       requires((Subsystem) e.nextElement());
     }
   }
@@ -193,7 +193,7 @@ public class CommandGroup extends Command {
     command.setParent(this);
 
     m_commands.addElement(new Entry(command, Entry.BRANCH_CHILD, timeout));
-    for (Enumeration e = command.getRequirements(); e.hasMoreElements(); ) {
+    for (Enumeration<?> e = command.getRequirements(); e.hasMoreElements(); ) {
       requires((Subsystem) e.nextElement());
     }
   }
@@ -283,7 +283,7 @@ public class CommandGroup extends Command {
       cmd.removed();
     }
 
-    Enumeration children = m_children.elements();
+    Enumeration<?> children = m_children.elements();
     while (children.hasMoreElements()) {
       Command cmd = ((Entry) children.nextElement()).m_command;
       cmd._cancel();
@@ -361,7 +361,7 @@ public class CommandGroup extends Command {
     for (int i = 0; i < m_children.size(); i++) {
       Command child = m_children.elementAt(i).m_command;
 
-      Enumeration requirements = command.getRequirements();
+      Enumeration<?> requirements = command.getRequirements();
 
       while (requirements.hasMoreElements()) {
         Object requirement = requirements.nextElement();
diff --git a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/ConditionalCommand.java b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/ConditionalCommand.java
index 1e188c2391..80c2903907 100644
--- a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/ConditionalCommand.java
+++ b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/ConditionalCommand.java
@@ -37,13 +37,13 @@ public abstract class ConditionalCommand extends Command {
 
   private void requireAll() {
     if (m_onTrue != null) {
-      for (Enumeration e = m_onTrue.getRequirements(); e.hasMoreElements(); ) {
+      for (Enumeration<?> e = m_onTrue.getRequirements(); e.hasMoreElements(); ) {
         requires((Subsystem) e.nextElement());
       }
     }
 
     if (m_onFalse != null) {
-      for (Enumeration e = m_onFalse.getRequirements(); e.hasMoreElements(); ) {
+      for (Enumeration<?> e = m_onFalse.getRequirements(); e.hasMoreElements(); ) {
         requires((Subsystem) e.nextElement());
       }
     }
diff --git a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Scheduler.java b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Scheduler.java
index 31519960a4..7d2c27fede 100644
--- a/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Scheduler.java
+++ b/wpilibOldCommands/src/main/java/edu/wpi/first/wpilibj/command/Scheduler.java
@@ -144,7 +144,7 @@ public final class Scheduler implements Sendable, AutoCloseable {
     // Only add if not already in
     if (!m_commandTable.containsKey(command)) {
       // Check that the requirements can be had
-      Enumeration requirements = command.getRequirements();
+      Enumeration<?> requirements = command.getRequirements();
       while (requirements.hasMoreElements()) {
         Subsystem lock = (Subsystem) requirements.nextElement();
         if (lock.getCurrentCommand() != null && !lock.getCurrentCommand().isInterruptible()) {
@@ -210,7 +210,7 @@ public final class Scheduler implements Sendable, AutoCloseable {
     }
 
     // Call every subsystem's periodic method
-    Enumeration subsystems = m_subsystems.getElements();
+    Enumeration<?> subsystems = m_subsystems.getElements();
     while (subsystems.hasMoreElements()) {
       ((Subsystem) subsystems.nextElement()).periodic();
     }
@@ -233,7 +233,7 @@ public final class Scheduler implements Sendable, AutoCloseable {
     m_additions.removeAllElements();
 
     // Add in the defaults
-    Enumeration locks = m_subsystems.getElements();
+    Enumeration<?> locks = m_subsystems.getElements();
     while (locks.hasMoreElements()) {
       Subsystem lock = (Subsystem) locks.nextElement();
       if (lock.getCurrentCommand() == null) {
@@ -276,7 +276,7 @@ public final class Scheduler implements Sendable, AutoCloseable {
     }
     element.remove();
 
-    Enumeration requirements = command.getRequirements();
+    Enumeration<?> requirements = command.getRequirements();
     while (requirements.hasMoreElements()) {
       ((Subsystem) requirements.nextElement()).setCurrentCommand(null);
     }
diff --git a/wpilibOldCommands/src/test/java/edu/wpi/first/wpilibj/MockHardwareExtension.java b/wpilibOldCommands/src/test/java/edu/wpi/first/wpilibj/MockHardwareExtension.java
index cdac72849d..e70f182a3b 100644
--- a/wpilibOldCommands/src/test/java/edu/wpi/first/wpilibj/MockHardwareExtension.java
+++ b/wpilibOldCommands/src/test/java/edu/wpi/first/wpilibj/MockHardwareExtension.java
@@ -30,10 +30,9 @@ public final class MockHardwareExtension implements BeforeAllCallback {
 
   private void initializeHardware() {
     HAL.initialize(500, 0);
-    DriverStationSim dsSim = new DriverStationSim();
-    dsSim.setDsAttached(true);
-    dsSim.setAutonomous(false);
-    dsSim.setEnabled(true);
-    dsSim.setTest(true);
+    DriverStationSim.setDsAttached(true);
+    DriverStationSim.setAutonomous(false);
+    DriverStationSim.setEnabled(true);
+    DriverStationSim.setTest(true);
   }
 }
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXRS450_Gyro.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXRS450_Gyro.java
index fcc57b9f18..a179f1f870 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXRS450_Gyro.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXRS450_Gyro.java
@@ -9,7 +9,6 @@ import edu.wpi.first.hal.HAL;
 import edu.wpi.first.hal.SimBoolean;
 import edu.wpi.first.hal.SimDevice;
 import edu.wpi.first.hal.SimDouble;
-import edu.wpi.first.wpilibj.interfaces.Gyro;
 import edu.wpi.first.wpilibj.smartdashboard.SendableRegistry;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
@@ -25,7 +24,7 @@ import java.nio.ByteOrder;
  * an ADXRS Gyro is supported.
  */
 @SuppressWarnings({"TypeName", "AbbreviationAsWordInName", "PMD.UnusedPrivateField"})
-public class ADXRS450_Gyro extends GyroBase implements Gyro, PIDSource, Sendable, AutoCloseable {
+public class ADXRS450_Gyro extends GyroBase {
   private static final double kSamplePeriod = 0.0005;
   private static final double kCalibrationSampleTime = 5.0;
   private static final double kDegreePerSecondPerLSB = 0.0125;
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogEncoder.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogEncoder.java
index df7492d5d5..dbbe72bd27 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogEncoder.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogEncoder.java
@@ -5,6 +5,7 @@
 package edu.wpi.first.wpilibj;
 
 import edu.wpi.first.hal.SimDevice;
+import edu.wpi.first.hal.SimDevice.Direction;
 import edu.wpi.first.hal.SimDouble;
 import edu.wpi.first.wpilibj.AnalogTriggerOutput.AnalogTriggerType;
 import edu.wpi.first.wpilibj.smartdashboard.SendableBuilder;
@@ -39,7 +40,7 @@ public class AnalogEncoder implements Sendable, AutoCloseable {
     m_simDevice = SimDevice.create("AnalogEncoder", m_analogInput.getChannel());
 
     if (m_simDevice != null) {
-      m_simPosition = m_simDevice.createDouble("Position", false, 0.0);
+      m_simPosition = m_simDevice.createDouble("Position", Direction.kInput, 0.0);
     }
 
     // Limits need to be 25% from each end
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogGyro.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogGyro.java
index a51e6e895d..11958cbd2d 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogGyro.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogGyro.java
@@ -9,7 +9,6 @@ import static edu.wpi.first.wpilibj.util.ErrorMessages.requireNonNullParam;
 import edu.wpi.first.hal.AnalogGyroJNI;
 import edu.wpi.first.hal.FRCNetComm.tResourceType;
 import edu.wpi.first.hal.HAL;
-import edu.wpi.first.wpilibj.interfaces.Gyro;
 import edu.wpi.first.wpilibj.smartdashboard.SendableRegistry;
 
 /**
@@ -21,7 +20,7 @@ import edu.wpi.first.wpilibj.smartdashboard.SendableRegistry;
  *
  * <p>This class is for gyro sensors that connect to an analog input.
  */
-public class AnalogGyro extends GyroBase implements Gyro, PIDSource, Sendable, AutoCloseable {
+public class AnalogGyro extends GyroBase {
   private static final double kDefaultVoltsPerDegreePerSecond = 0.007;
   protected AnalogInput m_analog;
   private boolean m_channelAllocated;
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalInput.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalInput.java
index 6cbfc8d4ea..867688fa06 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalInput.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalInput.java
@@ -17,7 +17,7 @@ import edu.wpi.first.wpilibj.smartdashboard.SendableRegistry;
  * elsewhere will automatically allocate digital inputs and outputs as required. This class is only
  * for devices like switches etc. that aren't implemented anywhere else.
  */
-public class DigitalInput extends DigitalSource implements Sendable, AutoCloseable {
+public class DigitalInput extends DigitalSource implements Sendable {
   private final int m_channel;
   private int m_handle;
 
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalOutput.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalOutput.java
index b005dff264..4bf63ae86f 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalOutput.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalOutput.java
@@ -15,7 +15,7 @@ import edu.wpi.first.wpilibj.smartdashboard.SendableRegistry;
  * Class to write digital outputs. This class will write digital outputs. Other devices that are
  * implemented elsewhere will automatically allocate digital inputs and outputs as required.
  */
-public class DigitalOutput extends DigitalSource implements Sendable, AutoCloseable {
+public class DigitalOutput extends DigitalSource implements Sendable {
   private static final int invalidPwmGenerator = 0;
   private int m_pwmGenerator = invalidPwmGenerator;
 
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/PIDController.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/PIDController.java
index f11e3dbfc2..505ab6962e 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/PIDController.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/PIDController.java
@@ -19,7 +19,7 @@ import edu.wpi.first.wpilibj.smartdashboard.SendableBuilder;
  * @deprecated Use {@link edu.wpi.first.wpilibj.controller.PIDController} instead.
  */
 @Deprecated(since = "2020", forRemoval = true)
-public class PIDController extends PIDBase implements Controller, AutoCloseable {
+public class PIDController extends PIDBase implements Controller {
   Notifier m_controlLoop = new Notifier(this::calculate);
 
   /**
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/SpeedController.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/SpeedController.java
index 50fd11cb27..f795ca77a0 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/SpeedController.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/SpeedController.java
@@ -5,6 +5,7 @@
 package edu.wpi.first.wpilibj;
 
 /** Interface for speed controlling devices. */
+@SuppressWarnings("removal")
 public interface SpeedController extends PIDOutput {
   /**
    * Common interface for setting the speed of a speed controller.
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/Ultrasonic.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/Ultrasonic.java
index c1bfc46f04..81c1bcf534 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/Ultrasonic.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/Ultrasonic.java
@@ -10,6 +10,7 @@ import edu.wpi.first.hal.FRCNetComm.tResourceType;
 import edu.wpi.first.hal.HAL;
 import edu.wpi.first.hal.SimBoolean;
 import edu.wpi.first.hal.SimDevice;
+import edu.wpi.first.hal.SimDevice.Direction;
 import edu.wpi.first.hal.SimDouble;
 import edu.wpi.first.wpilibj.smartdashboard.SendableBuilder;
 import edu.wpi.first.wpilibj.smartdashboard.SendableRegistry;
@@ -93,8 +94,8 @@ public class Ultrasonic implements PIDSource, Sendable, AutoCloseable {
   private synchronized void initialize() {
     m_simDevice = SimDevice.create("Ultrasonic", m_echoChannel.getChannel());
     if (m_simDevice != null) {
-      m_simRangeValid = m_simDevice.createBoolean("Range Valid", false, true);
-      m_simRange = m_simDevice.createDouble("Range (in)", false, 0.0);
+      m_simRangeValid = m_simDevice.createBoolean("Range Valid", Direction.kInput, true);
+      m_simRange = m_simDevice.createDouble("Range (in)", Direction.kInput, 0.0);
       m_pingChannel.setSimDevice(m_simDevice);
       m_echoChannel.setSimDevice(m_simDevice);
     }
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/Watchdog.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/Watchdog.java
index 3663669d30..80dabd068d 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/Watchdog.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/Watchdog.java
@@ -197,6 +197,7 @@ public class Watchdog implements Closeable, Comparable<Watchdog> {
     m_suppressTimeoutMessage = suppress;
   }
 
+  @SuppressWarnings("resource")
   private static void updateAlarm() {
     if (m_watchdogs.size() == 0) {
       NotifierJNI.cancelNotifierAlarm(m_notifier);
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/CallbackStore.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/CallbackStore.java
index 7710af3685..813cc6d62b 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/CallbackStore.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/CallbackStore.java
@@ -82,7 +82,7 @@ public class CallbackStore implements AutoCloseable {
     m_cancelType = -1;
   }
 
-  @SuppressWarnings("NoFinalizer")
+  @SuppressWarnings({"NoFinalizer", "deprecation"})
   @Override
   protected void finalize() throws Throwable {
     try {
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/DriverStationSim.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/DriverStationSim.java
index fac5dcbf2e..ab6a427a4f 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/DriverStationSim.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/DriverStationSim.java
@@ -11,7 +11,11 @@ import edu.wpi.first.wpilibj.DriverStation;
 
 /** Class to control a simulated driver station. */
 @SuppressWarnings({"PMD.UseUtilityClass", "PMD.GodClass", "PMD.ExcessivePublicCount"})
-public class DriverStationSim {
+public final class DriverStationSim {
+  private DriverStationSim() {
+    throw new UnsupportedOperationException("This is a utility class!");
+  }
+
   /**
    * Register a callback on whether the DS is enabled.
    *
diff --git a/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/Mechanism2D.java b/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/Mechanism2D.java
index 79de13dfdf..5d722a5f1a 100644
--- a/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/Mechanism2D.java
+++ b/wpilibj/src/main/java/edu/wpi/first/wpilibj/simulation/Mechanism2D.java
@@ -5,6 +5,7 @@
 package edu.wpi.first.wpilibj.simulation;
 
 import edu.wpi.first.hal.SimDevice;
+import edu.wpi.first.hal.SimDevice.Direction;
 import edu.wpi.first.hal.SimDouble;
 import java.util.HashMap;
 import java.util.Map;
@@ -23,7 +24,8 @@ public class Mechanism2D {
     ligamentPath = ligamentPath + "/angle";
     if (m_device != null) {
       if (!m_createdItems.containsKey(ligamentPath)) {
-        m_createdItems.put(ligamentPath, m_device.createDouble(ligamentPath, false, angle));
+        m_createdItems.put(
+            ligamentPath, m_device.createDouble(ligamentPath, Direction.kInput, angle));
       }
       m_createdItems.get(ligamentPath).set(angle);
     }
@@ -39,7 +41,8 @@ public class Mechanism2D {
     ligamentPath = ligamentPath + "/length";
     if (m_device != null) {
       if (!m_createdItems.containsKey(ligamentPath)) {
-        m_createdItems.put(ligamentPath, m_device.createDouble(ligamentPath, false, length));
+        m_createdItems.put(
+            ligamentPath, m_device.createDouble(ligamentPath, Direction.kInput, length));
       }
       m_createdItems.get(ligamentPath).set(length);
     }
diff --git a/wpilibj/src/test/java/edu/wpi/first/wpilibj/simulation/ElevatorSimTest.java b/wpilibj/src/test/java/edu/wpi/first/wpilibj/simulation/ElevatorSimTest.java
index 1903c852f6..0b954415a5 100644
--- a/wpilibj/src/test/java/edu/wpi/first/wpilibj/simulation/ElevatorSimTest.java
+++ b/wpilibj/src/test/java/edu/wpi/first/wpilibj/simulation/ElevatorSimTest.java
@@ -19,7 +19,7 @@ import org.junit.jupiter.api.Test;
 
 public class ElevatorSimTest {
   @Test
-  @SuppressWarnings("LocalVariableName")
+  @SuppressWarnings({"LocalVariableName", "resource"})
   public void testStateSpaceSimWithElevator() {
 
     var controller = new PIDController(10, 0, 0);
diff --git a/wpilibjExamples/src/main/java/edu/wpi/first/wpilibj/examples/pacgoat/subsystems/Collector.java b/wpilibjExamples/src/main/java/edu/wpi/first/wpilibj/examples/pacgoat/subsystems/Collector.java
index 6dfdc5594b..5dd83e6373 100644
--- a/wpilibjExamples/src/main/java/edu/wpi/first/wpilibj/examples/pacgoat/subsystems/Collector.java
+++ b/wpilibjExamples/src/main/java/edu/wpi/first/wpilibj/examples/pacgoat/subsystems/Collector.java
@@ -14,7 +14,7 @@ import edu.wpi.first.wpilibj.command.Subsystem;
  * The Collector subsystem has one motor for the rollers, a limit switch for ball detection, a
  * piston for opening and closing the claw, and a reed switch to check if the piston is open.
  */
-public class Collector extends Subsystem implements AutoCloseable {
+public class Collector extends Subsystem {
   // Constants for some useful speeds
   public static final double kForward = 1;
   public static final double kStop = 0;