WPILibJ (Java) API

package edu.wpi.first.wpilibj;

public class TimedRobot extends IterativeRobotBase {
  // Default period is 20ms (50Hz)
  public static final double kDefaultPeriod = 0.02;
  
  // Constructor
  public TimedRobot();
  public TimedRobot(double period);
  
  // Add custom periodic callback
  public void addPeriodic(Runnable callback, double periodSeconds);
  public void addPeriodic(Runnable callback, double periodSeconds, double offsetSeconds);
}

import edu.wpi.first.wpilibj.TimedRobot;
import edu.wpi.first.wpilibj.motorcontrol.Spark;

public class MyRobot extends TimedRobot {
  private Spark motor;
  
  @Override
  public void robotInit() {
    motor = new Spark(0);
  }
  
  @Override
  public void teleopPeriodic() {
    // Called every 20ms during teleop
    motor.set(0.5);
  }
  
  @Override
  public void disabledInit() {
    motor.set(0.0);
  }
}

package edu.wpi.first.wpilibj;

public final class DriverStation {
  // Get singleton instance
  public static DriverStation getInstance();
  
  // Robot state
  public static boolean isEnabled();
  public static boolean isDisabled();
  public static boolean isAutonomous();
  public static boolean isTeleop();
  public static boolean isTest();
  
  // Alliance and location
  public static Optional<Alliance> getAlliance();
  public static OptionalInt getLocation();
  
  // Match info
  public static double getMatchTime();
  public static MatchType getMatchType();
  public static int getMatchNumber();
  
  // Joystick input
  public static double getStickAxis(int stick, int axis);
  public static boolean getStickButton(int stick, int button);
  public static int getStickPOV(int stick, int pov);
  
  public enum Alliance { Red, Blue }
  public enum MatchType { None, Practice, Qualification, Elimination }
}

package edu.wpi.first.wpilibj;

public class AddressableLED implements AutoCloseable {
  public AddressableLED(int port);
  
  public void setLength(int length);
  public void setData(AddressableLEDBuffer data);
  public void start();
  public void stop();
}

public class AddressableLEDBuffer {
  public AddressableLEDBuffer(int length);
  
  public void setRGB(int index, int r, int g, int b);
  public void setHSV(int index, int h, int s, int v);
  public void setLED(int index, Color color);
}

package edu.wpi.first.wpilibj;

public final class Filesystem {
  // Get deploy directory path
  public static Path getDeployDirectory();
  
  // Get operating directory
  public static Path getOperatingDirectory();
  
  // Check if running on real robot
  public static boolean isReal();
}