auto-creamapi/src/main/java/CreamApiConfig.java

import org.apache.commons.configuration2.*;
import org.apache.commons.configuration2.builder.FileBasedConfigurationBuilder;
import org.apache.commons.configuration2.builder.fluent.Configurations;
import org.apache.commons.configuration2.ex.ConfigurationException;

import java.io.*;
import java.text.MessageFormat;
import java.util.*;

@SuppressWarnings("WeakerAccess")
public class CreamApiConfig {
    private static CreamApiConfig configInstance;
    private static final Configurations CONFIGS = new Configurations();

    private INIConfiguration config;
    private String path = "cream_api.ini";
    private Integer appId;
    private String language;
    private Boolean unlockAll;
    private Boolean extraProtection;
    private Boolean forceOffline;
    private Map<Integer, String> dlc = new HashMap<>();
    private List<String> languages = new ArrayList<>();

    private CreamApiConfig() {
        try {
            config = CONFIGS.ini(path);
            config.setCommentLeadingCharsUsedInInput(";");
        } catch (ConfigurationException e) {
            e.printStackTrace();
        }

        File langFile = new File("languages.txt");
        try {
            BufferedReader fIn = new BufferedReader(new FileReader(langFile));
            fIn.lines().filter(line -> !line.isEmpty() && !line.startsWith("#")).forEach(line -> languages.add(line));
        } catch (IOException e) {
            e.printStackTrace();
        }
        read();
    }

    public static synchronized CreamApiConfig getInstance() {
        if (configInstance == null) {
            configInstance = new CreamApiConfig();
        }
        return configInstance;
    }

    public void read() {
        appId = config.getInt("steam.appid");
        language = config.getString("steam.language");
        if (language == null) {
            language = "english";
        }
        unlockAll = config.getBoolean("steam.unlockall");
        extraProtection = config.getBoolean("steam.extraprotection");
        forceOffline = config.getBoolean("steam.forceoffline");
        final SubnodeConfiguration dlc_section = config.getSection("dlc");
        dlc_section.getKeys().forEachRemaining(k -> dlc.put(Integer.parseInt(k), dlc_section.getString(k)));
    }

    public void sync() throws ConfigurationException {
        FileBasedConfigurationBuilder<INIConfiguration> builder = CONFIGS.iniBuilder(path);
        config = builder.getConfiguration();
        config.setCommentLeadingCharsUsedInInput(";");

        config.setProperty("steam.appid", appId);
        config.setProperty("steam.language", language);
        config.setProperty("steam.unlockall", unlockAll);
        config.setProperty("steam.extraprotection", extraProtection);
        config.setProperty("steam.forceoffline", forceOffline);
        final SubnodeConfiguration dlc_section = config.getSection("dlc");
        dlc_section.clear();
        this.dlc.forEach((key, value) -> config.setProperty("dlc." + key.toString(), value));

        // default settings
        config.setProperty("steam.orgapi", "steam_api_o.dll");
        config.setProperty("steam.orgapi64", "steam_api64_o.dll");
        config.setProperty("steam.lowviolence", false);
        config.setProperty("steam_misc.disableuserinterface", false);

        builder.save();
    }

    // DLC list parsing

    public String getDlcListAsString() {
        StringBuilder sb = new StringBuilder();
        dlc.forEach((key, value) -> sb.append(key).append("=").append(value).append("\r\n"));
        return sb.toString();
    }

    public void setDlcListFromString(String str) {
        dlc.clear();
        Arrays.stream(str.split("\\R+")).forEach(line -> {
            final String[] split = line.split("\\s*=\\s*", 2);
            if (split.length == 2) dlc.put(Integer.parseInt(split[0]), split[1]);
            else System.err.println(MessageFormat.format("Error while splitting line: \"{0}\"", line));
        });
    }

    // GETTERS AND SETTERS

    public Integer getAppId() {
        return appId;
    }

    public void setAppId(Integer appId) {
        this.appId = appId;
    }

    public String getLanguage() {
        return language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }

    public Boolean getUnlockAll() {
        return unlockAll;
    }

    public void setUnlockAll(Boolean unlockAll) {
        this.unlockAll = unlockAll;
    }

    public Boolean getExtraProtection() {
        return extraProtection;
    }

    public void setExtraProtection(Boolean extraProtection) {
        this.extraProtection = extraProtection;
    }

    public Boolean getForceOffline() {
        return forceOffline;
    }

    public void setForceOffline(Boolean forceOffline) {
        this.forceOffline = forceOffline;
    }

    public List<String> getLanguages() {
        return languages;
    }

    public void setConfig(String path) throws ConfigurationException, IOException {
        File file = new File(path);
        if (!file.exists()) {
            final boolean newFile = file.createNewFile();
        }
        this.config = CONFIGS.ini(path);
        this.config.setCommentLeadingCharsUsedInInput(";");
        this.path = path;
    }
}