Rename our allwpilib (which is now 2020) to not have 2019 in the name

Change-Id: I3c07f85ed32ab8b97db765a9b43f2a6ce7da964a
diff --git a/wpilibc/src/main/native/cpp/AnalogEncoder.cpp b/wpilibc/src/main/native/cpp/AnalogEncoder.cpp
new file mode 100644
index 0000000..a194961
--- /dev/null
+++ b/wpilibc/src/main/native/cpp/AnalogEncoder.cpp
@@ -0,0 +1,104 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2019 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "frc/AnalogEncoder.h"
+
+#include "frc/AnalogInput.h"
+#include "frc/Counter.h"
+#include "frc/DriverStation.h"
+#include "frc/smartdashboard/SendableBuilder.h"
+
+using namespace frc;
+
+AnalogEncoder::AnalogEncoder(AnalogInput& analogInput)
+    : m_analogInput{&analogInput, NullDeleter<AnalogInput>{}},
+      m_analogTrigger{m_analogInput.get()},
+      m_counter{} {
+  Init();
+}
+
+AnalogEncoder::AnalogEncoder(AnalogInput* analogInput)
+    : m_analogInput{analogInput, NullDeleter<AnalogInput>{}},
+      m_analogTrigger{m_analogInput.get()},
+      m_counter{} {
+  Init();
+}
+
+AnalogEncoder::AnalogEncoder(std::shared_ptr<AnalogInput> analogInput)
+    : m_analogInput{std::move(analogInput)},
+      m_analogTrigger{m_analogInput.get()},
+      m_counter{} {
+  Init();
+}
+
+void AnalogEncoder::Init() {
+  m_simDevice = hal::SimDevice{"AnalogEncoder", m_analogInput->GetChannel()};
+
+  if (m_simDevice) {
+    m_simPosition = m_simDevice.CreateDouble("Position", false, 0.0);
+  }
+
+  m_analogTrigger.SetLimitsVoltage(1.25, 3.75);
+  m_counter.SetUpSource(
+      m_analogTrigger.CreateOutput(AnalogTriggerType::kRisingPulse));
+  m_counter.SetDownSource(
+      m_analogTrigger.CreateOutput(AnalogTriggerType::kFallingPulse));
+
+  SendableRegistry::GetInstance().AddLW(this, "DutyCycle Encoder",
+                                        m_analogInput->GetChannel());
+}
+
+units::turn_t AnalogEncoder::Get() const {
+  if (m_simPosition) return units::turn_t{m_simPosition.Get()};
+
+  // As the values are not atomic, keep trying until we get 2 reads of the same
+  // value If we don't within 10 attempts, error
+  for (int i = 0; i < 10; i++) {
+    auto counter = m_counter.Get();
+    auto pos = m_analogInput->GetVoltage();
+    auto counter2 = m_counter.Get();
+    auto pos2 = m_analogInput->GetVoltage();
+    if (counter == counter2 && pos == pos2) {
+      units::turn_t turns{counter + pos - m_positionOffset};
+      m_lastPosition = turns;
+      return turns;
+    }
+  }
+
+  frc::DriverStation::GetInstance().ReportWarning(
+      "Failed to read Analog Encoder. Potential Speed Overrun. Returning last "
+      "value");
+  return m_lastPosition;
+}
+
+double AnalogEncoder::GetPositionOffset() const { return m_positionOffset; }
+
+void AnalogEncoder::SetDistancePerRotation(double distancePerRotation) {
+  m_distancePerRotation = distancePerRotation;
+}
+
+double AnalogEncoder::GetDistancePerRotation() const {
+  return m_distancePerRotation;
+}
+
+double AnalogEncoder::GetDistance() const {
+  return Get().to<double>() * GetDistancePerRotation();
+}
+
+void AnalogEncoder::Reset() {
+  m_counter.Reset();
+  m_positionOffset = m_analogInput->GetVoltage();
+}
+
+void AnalogEncoder::InitSendable(SendableBuilder& builder) {
+  builder.SetSmartDashboardType("AbsoluteEncoder");
+  builder.AddDoubleProperty("Distance", [this] { return this->GetDistance(); },
+                            nullptr);
+  builder.AddDoubleProperty("Distance Per Rotation",
+                            [this] { return this->GetDistancePerRotation(); },
+                            nullptr);
+}