[hal, wpilib] Remove DigitalGlitchFilter (#7725)

hal/src/main/java/edu/wpi/first/hal/DigitalGlitchFilterJNI.java

@@ -1,65 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-package edu.wpi.first.hal;
-
-/**
- * Digital Glitch Filter JNI functions.
- *
- * @see "hal/DIO.h"
- */
-public class DigitalGlitchFilterJNI extends JNIWrapper {
-  /**
-   * Writes the filter index from the FPGA.
-   *
-   * <p>Set the filter index used to filter out short pulses.
-   *
-   * @param digitalPortHandle the digital port handle
-   * @param filterIndex the filter index (Must be in the range 0 - 3, where 0 means "none" and 1 - 3
-   *     means filter # filterIndex - 1)
-   * @see "HAL_SetFilterSelect"
-   */
-  public static native void setFilterSelect(int digitalPortHandle, int filterIndex);
-
-  /**
-   * Reads the filter index from the FPGA.
-   *
-   * <p>Gets the filter index used to filter out short pulses.
-   *
-   * @param digitalPortHandle the digital port handle
-   * @return the filter index (Must be in the range 0 - 3, where 0 means "none" and 1 - 3 means
-   *     filter # filterIndex - 1)
-   * @see "HAL_GetFilterSelect"
-   */
-  public static native int getFilterSelect(int digitalPortHandle);
-
-  /**
-   * Sets the filter period for the specified filter index.
-   *
-   * <p>Sets the filter period in FPGA cycles. Even though there are 2 different filter index
-   * domains (MXP vs HDR), ignore that distinction for now since it complicates the interface. That
-   * can be changed later.
-   *
-   * @param filterIndex the filter index, 0 - 2
-   * @param fpgaCycles the number of cycles that the signal must not transition to be counted as a
-   *     transition.
-   * @see "HAL_SetFilterPeriod"
-   */
-  public static native void setFilterPeriod(int filterIndex, int fpgaCycles);
-
-  /**
-   * Gets the filter period for the specified filter index.
-   *
-   * <p>Gets the filter period in FPGA cycles. Even though there are 2 different filter index
-   * domains (MXP vs HDR), ignore that distinction for now since it complicates the interface.
-   *
-   * @param filterIndex the filter index, 0 - 2
-   * @return The number of FPGA cycles of the filter period.
-   * @see "HAL_GetFilterPeriod"
-   */
-  public static native int getFilterPeriod(int filterIndex);
-
-  /** Utility class. */
-  private DigitalGlitchFilterJNI() {}
-}

hal/src/main/native/cpp/jni/DigitalGlitchFilterJNI.cpp

@@ -1,79 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include <jni.h>
-
-#include "HALUtil.h"
-#include "edu_wpi_first_hal_DigitalGlitchFilterJNI.h"
-#include "hal/DIO.h"
-
-using namespace hal;
-
-extern "C" {
-
-/*
- * Class:     edu_wpi_first_hal_DigitalGlitchFilterJNI
- * Method:    setFilterSelect
- * Signature: (II)V
- */
-JNIEXPORT void JNICALL
-Java_edu_wpi_first_hal_DigitalGlitchFilterJNI_setFilterSelect
-  (JNIEnv* env, jclass, jint id, jint filter_index)
-{
-  int32_t status = 0;
-
-  HAL_SetFilterSelect(static_cast<HAL_DigitalHandle>(id), filter_index,
-                      &status);
-  CheckStatus(env, status);
-}
-
-/*
- * Class:     edu_wpi_first_hal_DigitalGlitchFilterJNI
- * Method:    getFilterSelect
- * Signature: (I)I
- */
-JNIEXPORT jint JNICALL
-Java_edu_wpi_first_hal_DigitalGlitchFilterJNI_getFilterSelect
-  (JNIEnv* env, jclass, jint id)
-{
-  int32_t status = 0;
-
-  jint result =
-      HAL_GetFilterSelect(static_cast<HAL_DigitalHandle>(id), &status);
-  CheckStatus(env, status);
-  return result;
-}
-
-/*
- * Class:     edu_wpi_first_hal_DigitalGlitchFilterJNI
- * Method:    setFilterPeriod
- * Signature: (II)V
- */
-JNIEXPORT void JNICALL
-Java_edu_wpi_first_hal_DigitalGlitchFilterJNI_setFilterPeriod
-  (JNIEnv* env, jclass, jint filter_index, jint fpga_cycles)
-{
-  int32_t status = 0;
-
-  HAL_SetFilterPeriod(filter_index, fpga_cycles, &status);
-  CheckStatus(env, status);
-}
-
-/*
- * Class:     edu_wpi_first_hal_DigitalGlitchFilterJNI
- * Method:    getFilterPeriod
- * Signature: (I)I
- */
-JNIEXPORT jint JNICALL
-Java_edu_wpi_first_hal_DigitalGlitchFilterJNI_getFilterPeriod
-  (JNIEnv* env, jclass, jint filter_index)
-{
-  int32_t status = 0;
-
-  jint result = HAL_GetFilterPeriod(filter_index, &status);
-  CheckStatus(env, status);
-  return result;
-}
-
-}  // extern "C"

hal/src/main/native/include/hal/DIO.h

@@ -194,60 +194,6 @@ HAL_Bool HAL_IsPulsing(HAL_DigitalHandle dioPortHandle, int32_t* status);
  * @return true if a pulse on some line is in progress
  */
 HAL_Bool HAL_IsAnyPulsing(int32_t* status);
-
-/**
- * Writes the filter index from the FPGA.
- *
- * Set the filter index used to filter out short pulses.
- *
- * @param[in] dioPortHandle the digital port handle
- * @param[in] filterIndex   the filter index (Must be in the range 0 - 3, where
- *                          0 means "none" and 1 - 3 means filter # filterIndex
- *                          - 1)
- * @param[out] status       Error status variable. 0 on success.
- */
-void HAL_SetFilterSelect(HAL_DigitalHandle dioPortHandle, int32_t filterIndex,
-                         int32_t* status);
-
-/**
- * Reads the filter index from the FPGA.
- *
- * Gets the filter index used to filter out short pulses.
- *
- * @param[in] dioPortHandle the digital port handle
- * @param[out] status       Error status variable. 0 on success.
- * @return filterIndex  the filter index (Must be in the range 0 - 3, where 0
- *                      means "none" and 1 - 3 means filter # filterIndex - 1)
- */
-int32_t HAL_GetFilterSelect(HAL_DigitalHandle dioPortHandle, int32_t* status);
-
-/**
- * Sets the filter period for the specified filter index.
- *
- * Sets the filter period in FPGA cycles.  Even though there are 2 different
- * filter index domains (MXP vs HDR), ignore that distinction for now since it
- * complicates the interface.  That can be changed later.
- *
- * @param[in] filterIndex the filter index, 0 - 2
- * @param[in] value       the number of cycles that the signal must not
- *                        transition to be counted as a transition.
- * @param[out] status     Error status variable. 0 on success.
- */
-void HAL_SetFilterPeriod(int32_t filterIndex, int64_t value, int32_t* status);
-
-/**
- * Gets the filter period for the specified filter index.
- *
- * Gets the filter period in FPGA cycles.  Even though there are 2 different
- * filter index domains (MXP vs HDR), ignore that distinction for now since it
- * complicates the interface.  Set status to NiFpga_Status_SoftwareFault if the
- * filter values mismatch.
- *
- * @param[in] filterIndex the filter index, 0 - 2
- * @param[out] status     Error status variable. 0 on success.
- * @return                The number of FPGA cycles of the filter period.
- */
-int64_t HAL_GetFilterPeriod(int32_t filterIndex, int32_t* status);
 #ifdef __cplusplus
 }  // extern "C"
 #endif

hal/src/main/native/sim/DIO.cpp

@@ -269,32 +269,4 @@ HAL_Bool HAL_IsPulsing(HAL_DigitalHandle dioPortHandle, int32_t* status) {
 HAL_Bool HAL_IsAnyPulsing(int32_t* status) {
   return false;  // TODO(Thad) Figure this out
 }
-
-void HAL_SetFilterSelect(HAL_DigitalHandle dioPortHandle, int32_t filterIndex,
-                         int32_t* status) {
-  auto port = digitalChannelHandles->Get(dioPortHandle, HAL_HandleEnum::DIO);
-  if (port == nullptr) {
-    *status = HAL_HANDLE_ERROR;
-    return;
-  }
-  // mimics athena HAL
-  port->filterIndex = filterIndex % 4;
-}
-
-int32_t HAL_GetFilterSelect(HAL_DigitalHandle dioPortHandle, int32_t* status) {
-  auto port = digitalChannelHandles->Get(dioPortHandle, HAL_HandleEnum::DIO);
-  if (port == nullptr) {
-    *status = HAL_HANDLE_ERROR;
-    return 0;
-  }
-  return port->filterIndex;
-}
-
-void HAL_SetFilterPeriod(int32_t filterIndex, int64_t value, int32_t* status) {
-  // TODO(Thad) figure this out
-}
-
-int64_t HAL_GetFilterPeriod(int32_t filterIndex, int32_t* status) {
-  return 0;  // TODO(Thad) figure this out
-}
 }  // extern "C"

hal/src/main/native/systemcore/DIO.cpp

@@ -201,25 +201,4 @@ HAL_Bool HAL_IsAnyPulsing(int32_t* status) {
   return false;
 }
 
-void HAL_SetFilterSelect(HAL_DigitalHandle dioPortHandle, int32_t filterIndex,
-                         int32_t* status) {
-  *status = HAL_HANDLE_ERROR;
-  return;
-}
-
-int32_t HAL_GetFilterSelect(HAL_DigitalHandle dioPortHandle, int32_t* status) {
-  *status = HAL_HANDLE_ERROR;
-  return 0;
-}
-
-void HAL_SetFilterPeriod(int32_t filterIndex, int64_t value, int32_t* status) {
-  *status = HAL_HANDLE_ERROR;
-  return;
-}
-
-int64_t HAL_GetFilterPeriod(int32_t filterIndex, int32_t* status) {
-  *status = HAL_HANDLE_ERROR;
-  return 0;
-}
-
 }  // extern "C"

wpilibc/src/main/native/cpp/DigitalGlitchFilter.cpp

@@ -1,138 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include "frc/DigitalGlitchFilter.h"
-
-#include <algorithm>
-#include <array>
-#include <utility>
-
-#include <hal/Constants.h>
-#include <hal/DIO.h>
-#include <hal/FRCUsageReporting.h>
-#include <wpi/sendable/SendableRegistry.h>
-
-#include "frc/Counter.h"
-#include "frc/Encoder.h"
-#include "frc/Errors.h"
-#include "frc/SensorUtil.h"
-
-using namespace frc;
-
-std::array<bool, 3> DigitalGlitchFilter::m_filterAllocated = {
-    {false, false, false}};
-wpi::mutex DigitalGlitchFilter::m_mutex;
-
-DigitalGlitchFilter::DigitalGlitchFilter() {
-  m_channelIndex = AllocateFilterIndex();
-  if (m_channelIndex < 0) {
-    throw FRC_MakeError(err::NoAvailableResources,
-                        "No filters available to allocate.");
-  }
-  HAL_Report(HALUsageReporting::kResourceType_DigitalGlitchFilter,
-             m_channelIndex + 1);
-  wpi::SendableRegistry::AddLW(this, "DigitalGlitchFilter", m_channelIndex);
-}
-
-DigitalGlitchFilter::~DigitalGlitchFilter() {
-  if (m_channelIndex >= 0) {
-    std::scoped_lock lock(m_mutex);
-    m_filterAllocated[m_channelIndex] = false;
-  }
-}
-
-int DigitalGlitchFilter::AllocateFilterIndex() {
-  std::scoped_lock lock{m_mutex};
-  auto filter =
-      std::find(m_filterAllocated.begin(), m_filterAllocated.end(), false);
-
-  if (filter == m_filterAllocated.end()) {
-    return -1;
-  }
-  *filter = true;
-  return std::distance(m_filterAllocated.begin(), filter);
-}
-
-void DigitalGlitchFilter::Add(DigitalSource* input) {
-  DoAdd(input, m_channelIndex + 1);
-}
-
-void DigitalGlitchFilter::DoAdd(DigitalSource* input, int requestedIndex) {
-  // Some sources from Counters and Encoders are null. By pushing the check
-  // here, we catch the issue more generally.
-  if (input) {
-    // We don't support GlitchFilters on AnalogTriggers.
-    if (input->IsAnalogTrigger()) {
-      throw FRC_MakeError(
-          -1, "Analog Triggers not supported for DigitalGlitchFilters");
-    }
-    int32_t status = 0;
-    HAL_SetFilterSelect(input->GetPortHandleForRouting(), requestedIndex,
-                        &status);
-    FRC_CheckErrorStatus(status, "requested index {}", requestedIndex);
-
-    // Validate that we set it correctly.
-    int actualIndex =
-        HAL_GetFilterSelect(input->GetPortHandleForRouting(), &status);
-    FRC_CheckErrorStatus(status, "requested index {}", requestedIndex);
-    FRC_AssertMessage(actualIndex == requestedIndex,
-                      "HAL_SetFilterSelect({}) failed -> {}", requestedIndex,
-                      actualIndex);
-  }
-}
-
-void DigitalGlitchFilter::Add(Encoder* input) {
-  Add(input->m_aSource.get());
-  Add(input->m_bSource.get());
-}
-
-void DigitalGlitchFilter::Add(Counter* input) {
-  Add(input->m_upSource.get());
-  Add(input->m_downSource.get());
-}
-
-void DigitalGlitchFilter::Remove(DigitalSource* input) {
-  DoAdd(input, 0);
-}
-
-void DigitalGlitchFilter::Remove(Encoder* input) {
-  Remove(input->m_aSource.get());
-  Remove(input->m_bSource.get());
-}
-
-void DigitalGlitchFilter::Remove(Counter* input) {
-  Remove(input->m_upSource.get());
-  Remove(input->m_downSource.get());
-}
-
-void DigitalGlitchFilter::SetPeriodCycles(int fpgaCycles) {
-  int32_t status = 0;
-  HAL_SetFilterPeriod(m_channelIndex, fpgaCycles, &status);
-  FRC_CheckErrorStatus(status, "Channel {}", m_channelIndex);
-}
-
-void DigitalGlitchFilter::SetPeriodNanoSeconds(uint64_t nanoseconds) {
-  int32_t status = 0;
-  int fpgaCycles =
-      nanoseconds * HAL_GetSystemClockTicksPerMicrosecond() / 4 / 1000;
-  HAL_SetFilterPeriod(m_channelIndex, fpgaCycles, &status);
-  FRC_CheckErrorStatus(status, "Channel {}", m_channelIndex);
-}
-
-int DigitalGlitchFilter::GetPeriodCycles() {
-  int32_t status = 0;
-  int fpgaCycles = HAL_GetFilterPeriod(m_channelIndex, &status);
-  FRC_CheckErrorStatus(status, "Channel {}", m_channelIndex);
-  return fpgaCycles;
-}
-
-uint64_t DigitalGlitchFilter::GetPeriodNanoSeconds() {
-  int32_t status = 0;
-  int fpgaCycles = HAL_GetFilterPeriod(m_channelIndex, &status);
-  FRC_CheckErrorStatus(status, "Channel {}", m_channelIndex);
-  return static_cast<uint64_t>(fpgaCycles) * 1000L /
-         static_cast<uint64_t>(HAL_GetSystemClockTicksPerMicrosecond() / 4);
-}
-
-void DigitalGlitchFilter::InitSendable(wpi::SendableBuilder&) {}

wpilibc/src/main/native/include/frc/DigitalGlitchFilter.h

@@ -1,138 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#pragma once
-
-#include <stdint.h>
-
-#include <array>
-
-#include <wpi/mutex.h>
-#include <wpi/sendable/Sendable.h>
-#include <wpi/sendable/SendableHelper.h>
-
-#include "frc/DigitalSource.h"
-
-namespace frc {
-
-class Encoder;
-class Counter;
-
-/**
- * Class to enable glitch filtering on a set of digital inputs.
- *
- * This class will manage adding and removing digital inputs from a FPGA glitch
- * filter. The filter lets the user configure the time that an input must remain
- * high or low before it is classified as high or low.
- */
-class DigitalGlitchFilter : public wpi::Sendable,
-                            public wpi::SendableHelper<DigitalGlitchFilter> {
- public:
-  DigitalGlitchFilter();
-  ~DigitalGlitchFilter() override;
-
-  DigitalGlitchFilter(DigitalGlitchFilter&&) = default;
-  DigitalGlitchFilter& operator=(DigitalGlitchFilter&&) = default;
-
-  /**
-   * Assigns the DigitalSource to this glitch filter.
-   *
-   * @param input The DigitalSource to add.
-   */
-  void Add(DigitalSource* input);
-
-  /**
-   * Assigns the Encoder to this glitch filter.
-   *
-   * @param input The Encoder to add.
-   */
-  void Add(Encoder* input);
-
-  /**
-   * Assigns the Counter to this glitch filter.
-   *
-   * @param input The Counter to add.
-   */
-  void Add(Counter* input);
-
-  /**
-   * Removes a digital input from this filter.
-   *
-   * Removes the DigitalSource from this glitch filter and re-assigns it to
-   * the default filter.
-   *
-   * @param input The DigitalSource to remove.
-   */
-  void Remove(DigitalSource* input);
-
-  /**
-   * Removes an encoder from this filter.
-   *
-   * Removes the Encoder from this glitch filter and re-assigns it to
-   * the default filter.
-   *
-   * @param input The Encoder to remove.
-   */
-  void Remove(Encoder* input);
-
-  /**
-   * Removes a counter from this filter.
-   *
-   * Removes the Counter from this glitch filter and re-assigns it to
-   * the default filter.
-   *
-   * @param input The Counter to remove.
-   */
-  void Remove(Counter* input);
-
-  /**
-   * Sets the number of cycles that the input must not change state for.
-   *
-   * @param fpgaCycles The number of FPGA cycles.
-   */
-  void SetPeriodCycles(int fpgaCycles);
-
-  /**
-   * Sets the number of nanoseconds that the input must not change state for.
-   *
-   * @param nanoseconds The number of nanoseconds.
-   */
-  void SetPeriodNanoSeconds(uint64_t nanoseconds);
-
-  /**
-   * Gets the number of cycles that the input must not change state for.
-   *
-   * @return The number of cycles.
-   */
-  int GetPeriodCycles();
-
-  /**
-   * Gets the number of nanoseconds that the input must not change state for.
-   *
-   * @return The number of nanoseconds.
-   */
-  uint64_t GetPeriodNanoSeconds();
-
-  void InitSendable(wpi::SendableBuilder& builder) override;
-
- private:
-  int m_channelIndex;
-
-  // Sets the filter for the input to be the requested index. A value of 0
-  // disables the filter, and the filter value must be between 1 and 3,
-  // inclusive.
-  static void DoAdd(DigitalSource* input, int requested_index);
-
-  /**
-   * Allocates the next available filter index, or -1 if there are no filters
-   * available.
-   * @return the filter index
-   */
-  static int AllocateFilterIndex();
-
-  static wpi::mutex m_mutex;
-  static std::array<bool, 3> m_filterAllocated;
-};
-
-}  // namespace frc

wpilibc/src/main/native/include/frc/DigitalInput.h

@@ -12,8 +12,6 @@
 
 namespace frc {
 
-class DigitalGlitchFilter;
-
 /**
  * Class to read a digital input.
  *
@@ -81,8 +79,6 @@ class DigitalInput : public DigitalSource,
  private:
   int m_channel;
   hal::Handle<HAL_DigitalHandle, HAL_FreeDIOPort> m_handle;
-
-  friend class DigitalGlitchFilter;
 };
 
 }  // namespace frc

wpilibc/src/main/native/include/frc/Encoder.h

@@ -17,7 +17,6 @@
 namespace frc {
 
 class DigitalSource;
-class DigitalGlitchFilter;
 
 /**
  * Class to read quad encoders.
@@ -375,8 +374,6 @@ class Encoder : public CounterBase,
   std::shared_ptr<DigitalSource> m_bSource;  // The B phase of the quad encoder
   std::shared_ptr<DigitalSource> m_indexSource = nullptr;
   hal::Handle<HAL_EncoderHandle, HAL_FreeEncoder> m_encoder;
-
-  friend class DigitalGlitchFilter;
 };
 
 }  // namespace frc

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

@@ -1,192 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-package edu.wpi.first.wpilibj;
-
-import edu.wpi.first.hal.DigitalGlitchFilterJNI;
-import edu.wpi.first.hal.FRCNetComm.tResourceType;
-import edu.wpi.first.hal.HAL;
-import edu.wpi.first.hal.util.AllocationException;
-import edu.wpi.first.util.sendable.Sendable;
-import edu.wpi.first.util.sendable.SendableBuilder;
-import edu.wpi.first.util.sendable.SendableRegistry;
-import java.util.concurrent.locks.Lock;
-import java.util.concurrent.locks.ReentrantLock;
-
-/**
- * Class to enable glitch filtering on a set of digital inputs. This class will manage adding and
- * removing digital inputs from an FPGA glitch filter. The filter lets the user configure the time
- * that an input must remain high or low before it is classified as high or low.
- */
-public class DigitalGlitchFilter implements Sendable, AutoCloseable {
-  /** Configures the Digital Glitch Filter to its default settings. */
-  @SuppressWarnings("this-escape")
-  public DigitalGlitchFilter() {
-    m_channelIndex = allocateFilterIndex();
-    if (m_channelIndex < 0) {
-      throw new AllocationException("No filters available to allocate.");
-    }
-    HAL.report(tResourceType.kResourceType_DigitalGlitchFilter, m_channelIndex + 1, 0);
-    SendableRegistry.addLW(this, "DigitalGlitchFilter", m_channelIndex);
-  }
-
-  @Override
-  public void close() {
-    SendableRegistry.remove(this);
-    if (m_channelIndex >= 0) {
-      m_mutex.lock();
-      try {
-        m_filterAllocated[m_channelIndex] = false;
-      } finally {
-        m_mutex.unlock();
-      }
-
-      m_channelIndex = -1;
-    }
-  }
-
-  /**
-   * Allocates the next available filter index, or -1 if there are no filters available.
-   *
-   * @return the filter index
-   */
-  private static int allocateFilterIndex() {
-    m_mutex.lock();
-    try {
-      for (int index = 0; index < m_filterAllocated.length; index++) {
-        if (!m_filterAllocated[index]) {
-          m_filterAllocated[index] = true;
-          return index;
-        }
-      }
-    } finally {
-      m_mutex.unlock();
-    }
-    return -1;
-  }
-
-  private static void setFilter(DigitalSource input, int channelIndex) {
-    if (input != null) { // Counter might have just one input
-      // analog triggers are not supported for DigitalGlitchFilters
-      if (input.isAnalogTrigger()) {
-        throw new IllegalStateException("Analog Triggers not supported for DigitalGlitchFilters");
-      }
-      DigitalGlitchFilterJNI.setFilterSelect(input.getPortHandleForRouting(), channelIndex);
-
-      int selected = DigitalGlitchFilterJNI.getFilterSelect(input.getPortHandleForRouting());
-      if (selected != channelIndex) {
-        throw new IllegalStateException(
-            "DigitalGlitchFilterJNI.setFilterSelect(" + channelIndex + ") failed -> " + selected);
-      }
-    }
-  }
-
-  /**
-   * Assigns the DigitalSource to this glitch filter.
-   *
-   * @param input The DigitalSource to add.
-   */
-  public void add(DigitalSource input) {
-    setFilter(input, m_channelIndex + 1);
-  }
-
-  /**
-   * Assigns the Encoder to this glitch filter.
-   *
-   * @param input The Encoder to add.
-   */
-  public void add(Encoder input) {
-    add(input.m_aSource);
-    add(input.m_bSource);
-  }
-
-  /**
-   * Assigns the Counter to this glitch filter.
-   *
-   * @param input The Counter to add.
-   */
-  public void add(Counter input) {
-    add(input.m_upSource);
-    add(input.m_downSource);
-  }
-
-  /**
-   * Removes this filter from the given digital input.
-   *
-   * @param input The DigitalSource to stop filtering.
-   */
-  public void remove(DigitalSource input) {
-    setFilter(input, 0);
-  }
-
-  /**
-   * Removes this filter from the given Encoder.
-   *
-   * @param input the Encoder to stop filtering.
-   */
-  public void remove(Encoder input) {
-    remove(input.m_aSource);
-    remove(input.m_bSource);
-  }
-
-  /**
-   * Removes this filter from the given Counter.
-   *
-   * @param input The Counter to stop filtering.
-   */
-  public void remove(Counter input) {
-    remove(input.m_upSource);
-    remove(input.m_downSource);
-  }
-
-  /**
-   * Sets the number of FPGA cycles that the input must hold steady to pass through this glitch
-   * filter.
-   *
-   * @param fpgaCycles The number of FPGA cycles.
-   */
-  public void setPeriodCycles(int fpgaCycles) {
-    DigitalGlitchFilterJNI.setFilterPeriod(m_channelIndex, fpgaCycles);
-  }
-
-  /**
-   * Sets the number of nanoseconds that the input must hold steady to pass through this glitch
-   * filter.
-   *
-   * @param nanoseconds The number of nanoseconds.
-   */
-  public void setPeriodNanoSeconds(long nanoseconds) {
-    int fpgaCycles = (int) (nanoseconds * SensorUtil.kSystemClockTicksPerMicrosecond / 4 / 1000);
-    setPeriodCycles(fpgaCycles);
-  }
-
-  /**
-   * Gets the number of FPGA cycles that the input must hold steady to pass through this glitch
-   * filter.
-   *
-   * @return The number of cycles.
-   */
-  public int getPeriodCycles() {
-    return DigitalGlitchFilterJNI.getFilterPeriod(m_channelIndex);
-  }
-
-  /**
-   * Gets the number of nanoseconds that the input must hold steady to pass through this glitch
-   * filter.
-   *
-   * @return The number of nanoseconds.
-   */
-  public long getPeriodNanoSeconds() {
-    int fpgaCycles = getPeriodCycles();
-
-    return fpgaCycles * 1000L / (SensorUtil.kSystemClockTicksPerMicrosecond / 4);
-  }
-
-  @Override
-  public void initSendable(SendableBuilder builder) {}
-
-  private int m_channelIndex;
-  private static final Lock m_mutex = new ReentrantLock(true);
-  private static final boolean[] m_filterAllocated = new boolean[3];
-}