Implements AutoCloseable for types, replacing free() (#1048)

wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXL345_I2C.java

@@ -93,9 +93,9 @@ public class ADXL345_I2C extends SensorBase implements Accelerometer, Sendable {
   }
 
   @Override
-  public void free() {
-    super.free();
-    m_i2c.free();
+  public void close() {
+    super.close();
+    m_i2c.close();
   }
 
   @Override

wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXL345_SPI.java

@@ -79,9 +79,9 @@ public class ADXL345_SPI extends SensorBase implements Accelerometer, Sendable {
   }
 
   @Override
-  public void free() {
-    super.free();
-    m_spi.free();
+  public void close() {
+    super.close();
+    m_spi.close();
   }
 
   /**

wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXL362.java

@@ -93,7 +93,7 @@ public class ADXL362 extends SensorBase implements Accelerometer, Sendable {
     transferBuffer.put(1, kPartIdRegister);
     m_spi.transaction(transferBuffer, transferBuffer, 3);
     if (transferBuffer.get(2) != (byte) 0xF2) {
-      m_spi.free();
+      m_spi.close();
       m_spi = null;
       DriverStation.reportError("could not find ADXL362 on SPI port " + port.value, false);
       return;
@@ -112,10 +112,10 @@ public class ADXL362 extends SensorBase implements Accelerometer, Sendable {
   }
 
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_spi != null) {
-      m_spi.free();
+      m_spi.close();
       m_spi = null;
     }
   }

wpilibj/src/main/java/edu/wpi/first/wpilibj/ADXRS450_Gyro.java

@@ -64,7 +64,7 @@ public class ADXRS450_Gyro extends GyroBase implements Gyro, PIDSource, Sendable
 
     // Validate the part ID
     if ((readRegister(kPIDRegister) & 0xff00) != 0x5200) {
-      m_spi.free();
+      m_spi.close();
       m_spi = null;
       DriverStation.reportError("could not find ADXRS450 gyro on SPI port " + port.value,
           false);
@@ -141,10 +141,10 @@ public class ADXRS450_Gyro extends GyroBase implements Gyro, PIDSource, Sendable
    * Delete (free) the spi port used for the gyro and stop accumulating.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_spi != null) {
-      m_spi.free();
+      m_spi.close();
       m_spi = null;
     }
   }

wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogAccelerometer.java

@@ -67,10 +67,10 @@ public class AnalogAccelerometer extends SensorBase implements PIDSource, Sendab
    * Delete the analog components used for the accelerometer.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_analogChannel != null && m_allocatedChannel) {
-      m_analogChannel.free();
+      m_analogChannel.close();
     }
     m_analogChannel = null;
   }

wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogGyro.java

@@ -119,10 +119,10 @@ public class AnalogGyro extends GyroBase implements Gyro, PIDSource, Sendable {
    * Delete (free) the accumulator and the analog components used for the gyro.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_analog != null && m_channelAllocated) {
-      m_analog.free();
+      m_analog.close();
     }
     m_analog = null;
     AnalogGyroJNI.freeAnalogGyro(m_gyroHandle);

wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogInput.java

@@ -54,8 +54,8 @@ public class AnalogInput extends SensorBase implements PIDSource, Sendable {
    * Channel destructor.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     AnalogJNI.freeAnalogInputPort(m_port);
     m_port = 0;
     m_channel = 0;

wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogOutput.java

@@ -40,8 +40,8 @@ public class AnalogOutput extends SendableBase implements Sendable {
    * Channel destructor.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     AnalogJNI.freeAnalogOutputPort(m_port);
     m_port = 0;
     m_channel = 0;

wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogPotentiometer.java

@@ -158,10 +158,10 @@ public class AnalogPotentiometer extends SensorBase implements Potentiometer, Se
    * Frees this resource.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_initAnalogInput) {
-      m_analogInput.free();
+      m_analogInput.close();
       m_analogInput = null;
       m_initAnalogInput = false;
     }

wpilibj/src/main/java/edu/wpi/first/wpilibj/AnalogTrigger.java

@@ -78,12 +78,12 @@ public class AnalogTrigger extends SensorBase implements Sendable {
    * Release the resources used by this object.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     AnalogJNI.cleanAnalogTrigger(m_port);
     m_port = 0;
     if (m_ownsAnalog && m_analogInput != null) {
-      m_analogInput.free();
+      m_analogInput.close();
     }
   }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/Counter.java

@@ -180,8 +180,8 @@ public class Counter extends SensorBase implements CounterBase, Sendable, PIDSou
   }
 
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     setUpdateWhenEmpty(true);
 
     clearUpSource();
@@ -222,7 +222,7 @@ public class Counter extends SensorBase implements CounterBase, Sendable, PIDSou
    */
   public void setUpSource(DigitalSource source) {
     if (m_upSource != null && m_allocatedUpSource) {
-      m_upSource.free();
+      m_upSource.close();
       m_allocatedUpSource = false;
     }
     m_upSource = source;
@@ -263,7 +263,7 @@ public class Counter extends SensorBase implements CounterBase, Sendable, PIDSou
    */
   public void clearUpSource() {
     if (m_upSource != null && m_allocatedUpSource) {
-      m_upSource.free();
+      m_upSource.close();
       m_allocatedUpSource = false;
     }
     m_upSource = null;
@@ -292,7 +292,7 @@ public class Counter extends SensorBase implements CounterBase, Sendable, PIDSou
     requireNonNull(source, "The Digital Source given was null");
 
     if (m_downSource != null && m_allocatedDownSource) {
-      m_downSource.free();
+      m_downSource.close();
       m_allocatedDownSource = false;
     }
     CounterJNI.setCounterDownSource(m_counter, source.getPortHandleForRouting(),
@@ -332,7 +332,7 @@ public class Counter extends SensorBase implements CounterBase, Sendable, PIDSou
    */
   public void clearDownSource() {
     if (m_downSource != null && m_allocatedDownSource) {
-      m_downSource.free();
+      m_downSource.close();
       m_allocatedDownSource = false;
     }
     m_downSource = null;

wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalGlitchFilter.java

@@ -43,8 +43,8 @@ public class DigitalGlitchFilter extends SensorBase {
   /**
    * Free the resources used by this object.
    */
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_channelIndex >= 0) {
       synchronized (m_mutex) {
         m_filterAllocated[m_channelIndex] = false;

wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalInput.java

@@ -40,8 +40,8 @@ public class DigitalInput extends DigitalSource implements Sendable {
   /**
    * Frees the resources for this output.
    */
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_interrupt != 0) {
       cancelInterrupts();
     }

wpilibj/src/main/java/edu/wpi/first/wpilibj/DigitalOutput.java

@@ -44,8 +44,8 @@ public class DigitalOutput extends SendableBase implements Sendable {
    * Free the resources associated with a digital output.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     // disable the pwm only if we have allocated it
     if (m_pwmGenerator != invalidPwmGenerator) {
       disablePWM();

wpilibj/src/main/java/edu/wpi/first/wpilibj/DoubleSolenoid.java

@@ -86,11 +86,10 @@ public class DoubleSolenoid extends SolenoidBase implements Sendable {
    * Destructor.
    */
   @Override
-  public synchronized void free() {
-    super.free();
+  public synchronized void close() {
+    super.close();
     SolenoidJNI.freeSolenoidPort(m_forwardHandle);
     SolenoidJNI.freeSolenoidPort(m_reverseHandle);
-    super.free();
   }
 
   /**

wpilibj/src/main/java/edu/wpi/first/wpilibj/Encoder.java

@@ -294,18 +294,18 @@ public class Encoder extends SensorBase implements CounterBase, PIDSource, Senda
    * Free the resources used by this object.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_aSource != null && m_allocatedA) {
-      m_aSource.free();
+      m_aSource.close();
       m_allocatedA = false;
     }
     if (m_bSource != null && m_allocatedB) {
-      m_bSource.free();
+      m_bSource.close();
       m_allocatedB = false;
     }
     if (m_indexSource != null && m_allocatedI) {
-      m_indexSource.free();
+      m_indexSource.close();
       m_allocatedI = false;
     }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/I2C.java

@@ -22,7 +22,7 @@ import static java.util.Objects.requireNonNull;
  * <p>This class is intended to be used by sensor (and other I2C device) drivers. It probably should
  * not be used directly.
  */
-public class I2C {
+public class I2C implements AutoCloseable {
   public enum Port {
     kOnboard(0), kMXP(1);
 
@@ -52,10 +52,16 @@ public class I2C {
     HAL.report(tResourceType.kResourceType_I2C, deviceAddress);
   }
 
+  @Deprecated
+  public void free() {
+    close();
+  }
+
   /**
    * Destructor.
    */
-  public void free() {
+  @Override
+  public void close() {
     I2CJNI.i2CClose(m_port);
   }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/InterruptableSensorBase.java

@@ -48,8 +48,8 @@ public abstract class InterruptableSensorBase extends SensorBase {
    * Frees the resources for this output.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_interrupt != 0) {
       cancelInterrupts();
     }

wpilibj/src/main/java/edu/wpi/first/wpilibj/NidecBrushless.java

@@ -53,10 +53,10 @@ public class NidecBrushless extends SendableBase implements SpeedController, Mot
    * Free the resources used by this object.
    */
   @Override
-  public void free() {
-    super.free();
-    m_dio.free();
-    m_pwm.free();
+  public void close() {
+    super.close();
+    m_dio.close();
+    m_pwm.close();
   }
 
   /**

wpilibj/src/main/java/edu/wpi/first/wpilibj/PIDController.java

@@ -92,8 +92,8 @@ public class PIDController extends PIDBase implements Controller {
    * Free the PID object.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     m_controlLoop.stop();
     m_thisMutex.lock();
     try {

wpilibj/src/main/java/edu/wpi/first/wpilibj/PWM.java

@@ -71,8 +71,8 @@ public class PWM extends SendableBase implements Sendable {
    * <p>Free the resource associated with the PWM channel and set the value to 0.
    */
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     if (m_handle == 0) {
       return;
     }

wpilibj/src/main/java/edu/wpi/first/wpilibj/Relay.java

@@ -141,8 +141,8 @@ public class Relay extends SendableBase implements MotorSafety, Sendable {
   }
 
   @Override
-  public void free() {
-    super.free();
+  public void close() {
+    super.close();
     freeRelay();
   }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/RobotBase.java

@@ -32,7 +32,7 @@ import edu.wpi.first.wpilibj.util.WPILibVersion;
  * run to completion before the OperatorControl code could start. In the future the Autonomous code
  * might be spawned as a task, then killed at the end of the Autonomous period.
  */
-public abstract class RobotBase {
+public abstract class RobotBase implements AutoCloseable {
   /**
    * The ID of the main Java thread.
    */
@@ -93,10 +93,15 @@ public abstract class RobotBase {
     LiveWindow.setEnabled(false);
   }
 
+  @Deprecated
+  public void free() {
+  }
+
   /**
    * Free the resources for a RobotBase class.
    */
-  public void free() {
+  @Override
+  public void close() {
   }
 
   /**

wpilibj/src/main/java/edu/wpi/first/wpilibj/RobotDrive.java

@@ -25,7 +25,7 @@ import static java.util.Objects.requireNonNull;
  *             or {@link edu.wpi.first.wpilibj.drive.MecanumDrive} classes instead.
  */
 @Deprecated
-public class RobotDrive implements MotorSafety {
+public class RobotDrive implements MotorSafety, AutoCloseable {
   protected MotorSafetyHelper m_safetyHelper;
 
   /**
@@ -662,22 +662,28 @@ public class RobotDrive implements MotorSafety {
     m_maxOutput = maxOutput;
   }
 
+  @Deprecated
+  public void free() {
+    close();
+  }
+
   /**
    * Free the speed controllers if they were allocated locally.
    */
-  public void free() {
+  @Override
+  public void close() {
     if (m_allocatedSpeedControllers) {
       if (m_frontLeftMotor != null) {
-        ((PWM) m_frontLeftMotor).free();
+        ((PWM) m_frontLeftMotor).close();
       }
       if (m_frontRightMotor != null) {
-        ((PWM) m_frontRightMotor).free();
+        ((PWM) m_frontRightMotor).close();
       }
       if (m_rearLeftMotor != null) {
-        ((PWM) m_rearLeftMotor).free();
+        ((PWM) m_rearLeftMotor).close();
       }
       if (m_rearRightMotor != null) {
-        ((PWM) m_rearRightMotor).free();
+        ((PWM) m_rearRightMotor).close();
       }
     }
   }

wpilibj/src/main/java/edu/wpi/first/wpilibj/SPI.java

@@ -16,7 +16,7 @@ import edu.wpi.first.wpilibj.hal.SPIJNI;
 /**
  * Represents a SPI bus port.
  */
-public class SPI {
+public class SPI implements AutoCloseable {
   public enum Port {
     kOnboardCS0(0), kOnboardCS1(1), kOnboardCS2(2), kOnboardCS3(3), kMXP(4);
 
@@ -49,12 +49,19 @@ public class SPI {
     HAL.report(tResourceType.kResourceType_SPI, devices);
   }
 
+
+  @Deprecated
+  public void free() {
+    close();
+  }
+
   /**
    * Free the resources used by this object.
    */
-  public void free() {
+  @Override
+  public void close() {
     if (m_accum != null) {
-      m_accum.free();
+      m_accum.close();
       m_accum = null;
     }
     SPIJNI.spiClose(m_port);
@@ -416,7 +423,7 @@ public class SPI {
 
   private static final int kAccumulateDepth = 2048;
 
-  private static class Accumulator {
+  private static class Accumulator implements AutoCloseable {
     Accumulator(int port, int xferSize, int validMask, int validValue, int dataShift,
                 int dataSize, boolean isSigned, boolean bigEndian) {
       m_notifier = new Notifier(this::update);
@@ -432,7 +439,8 @@ public class SPI {
       m_port = port;
     }
 
-    void free() {
+    @Override
+    public void close() {
       m_notifier.stop();
     }
 
@@ -570,7 +578,7 @@ public class SPI {
    */
   public void freeAccumulator() {
     if (m_accum != null) {
-      m_accum.free();
+      m_accum.close();
       m_accum = null;
     }
     freeAuto();

wpilibj/src/main/java/edu/wpi/first/wpilibj/SendableBase.java

@@ -13,7 +13,7 @@ import edu.wpi.first.wpilibj.livewindow.LiveWindow;
  * Base class for all sensors. Stores most recent status information as well as containing utility
  * functions for checking channels and error processing.
  */
-public abstract class SendableBase implements Sendable {
+public abstract class SendableBase implements Sendable, AutoCloseable {
   private String m_name = "";
   private String m_subsystem = "Ungrouped";
 
@@ -35,10 +35,16 @@ public abstract class SendableBase implements Sendable {
     }
   }
 
+  @Deprecated
+  public void free() {
+    close();
+  }
+
   /**
    * Free the resources used by this object.
    */
-  public void free() {
+  @Override
+  public void close() {
     LiveWindow.remove(this);
   }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/SerialPort.java

@@ -197,7 +197,7 @@ public class SerialPort {
   /**
    * Destructor.
    */
-  public void free() {
+  public void close() {
     SerialPortJNI.serialClose(m_port);
   }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/Solenoid.java

@@ -55,8 +55,8 @@ public class Solenoid extends SolenoidBase implements Sendable {
    * Destructor.
    */
   @Override
-  public synchronized void free() {
-    super.free();
+  public synchronized void close() {
+    super.close();
     SolenoidJNI.freeSolenoidPort(m_solenoidHandle);
     m_solenoidHandle = 0;
   }

wpilibj/src/main/java/edu/wpi/first/wpilibj/Ultrasonic.java

@@ -191,21 +191,21 @@ public class Ultrasonic extends SensorBase implements PIDSource, Sendable {
    * sensor).
    */
   @Override
-  public synchronized void free() {
-    super.free();
+  public synchronized void close() {
+    super.close();
     final boolean wasAutomaticMode = m_automaticEnabled;
     setAutomaticMode(false);
     if (m_allocatedChannels) {
       if (m_pingChannel != null) {
-        m_pingChannel.free();
+        m_pingChannel.close();
       }
       if (m_echoChannel != null) {
-        m_echoChannel.free();
+        m_echoChannel.close();
       }
     }
 
     if (m_counter != null) {
-      m_counter.free();
+      m_counter.close();
       m_counter = null;
     }
 

wpilibj/src/main/java/edu/wpi/first/wpilibj/interfaces/Gyro.java

@@ -10,7 +10,7 @@ package edu.wpi.first.wpilibj.interfaces;
 /**
  * Interface for yaw rate gyros.
  */
-public interface Gyro {
+public interface Gyro extends AutoCloseable {
   /**
    * Calibrate the gyro by running for a number of samples and computing the center value. Then use
    * the center value as the Accumulator center value for subsequent measurements. It's important to
@@ -52,5 +52,12 @@ public interface Gyro {
   /**
    * Free the resources used by the gyro.
    */
+  @Deprecated
   void free();
+
+  /**
+   * Free the resources used by the gyro.
+   */
+  @Override
+  void close();
 }