RoboRio Robot Configuration Picker

Robot.java

public class Robot extends SampleRobot
{
    // specify all possible robot configs, with the default (first one) being the competition config
    // so it can default to that if we don't load the config.txt file properly
    public static RobotConfig config = RobotConfigPicker.get(new RobotConfig[] { new RRRConfigCompetition(), new RRRConfigPractice()});

    public static boolean isCompBot()
    {
        return config instanceof RRRConfigCompetition;
    }
    
    ...
    rest of code
    ...
}

RobotConfigPicker.java

package org.wfrobotics.reuse.config;

import java.io.BufferedReader;
import java.io.FileReader;

import org.wfrobotics.robot.config.robotConfigs.RobotConfig;

import edu.wpi.first.wpilibj.DriverStation;

public class RobotConfigPicker
{
    /**
     * Read the contents of the text file on the Rio at ~/config.txt to match to a config class's name
     * and set the activeConfig which can be grabbed via {@link #get()}. Will print an error to the
     * driver station and select the first config in the array if it can't match a name.
     * @param configs Array of {@link RobotConfig} configs
     */
    public static RobotConfig get(RobotConfig[] configs)
    {
        return get(configs, "~/config.txt");
    }

    /**
     * Read the contents of the text file on the Rio at {@code file} to match to a config class's name
     * and set the activeConfig which can be grabbed via {@link #get()}. Will print an error to the
     * driver station and select the first config in the array if it can't match a name.
     * @param configs Array of {@link RobotConfigBase} configs
     * @param file custom file path to look for the config name
     */
    public static RobotConfig get(RobotConfig[] configs, String file)
    {
        String configFilePath = getFile(file);
        String configName = readFile(configFilePath);

        for (RobotConfig robotConfig : configs)
        {
            // try to match the file's config name to any of the configs passed in to this class
            if(robotConfig.getClass().getSimpleName().toLowerCase().equals(configName.toLowerCase()))
            {
                // found, so return the config
                DriverStation.reportWarning("      Using config:   " + robotConfig.getClass().getSimpleName(), false);
                return robotConfig;
            }
        }

        // couldn't find a config, so we revert to the first one passed in
        // but throw an error so the Driver station is aware
        DriverStation.reportError("      Failed to find config file, using config instead:   " + configs[0].getClass().getSimpleName(), false);
        return configs[0];
    }

    private static String readFile(String filename)
    {
        String configName = "";
        try
        {
            BufferedReader reader = new BufferedReader(new FileReader(filename));
            String line;
            if ((line = reader.readLine()) != null)
            {
                configName = line;
            }
            reader.close();
            return configName;
        }
        catch (Exception e)
        {
            System.err.format("Exception occurred trying to read '%s'", filename);
            return configName;
        }


    }

    private static String getFile(String filePath) {
        filePath = filePath.replaceFirst("^~", System.getProperty("user.home"));
        return filePath;
    }
}