Initialization and Setup

/**
 * Initialize MMKV with default configuration.
 * You must call one of the initialize() methods on App startup process before using MMKV.
 * @param context The context of Android App, usually from Application
 * @return The root folder of MMKV, defaults to $(FilesDir)/mmkv
 */
public static String initialize(Context context);

public class MyApplication extends Application {
    @Override
    public void onCreate() {
        super.onCreate();
        
        // Initialize MMKV with default settings
        String rootDir = MMKV.initialize(this);
        Log.d("MMKV", "MMKV initialized with root: " + rootDir);
    }
}

/**
 * Initialize MMKV with customize log level.
 * @param context The context of Android App, usually from Application
 * @param logLevel The log level of MMKV, defaults to MMKVLogLevel.LevelInfo
 * @return The root folder of MMKV
 */
public static String initialize(Context context, MMKVLogLevel logLevel);

// Debug build with verbose logging
String rootDir = MMKV.initialize(this, MMKVLogLevel.LevelDebug);

// Production build with minimal logging
String rootDir = MMKV.initialize(this, MMKVLogLevel.LevelError);

/**
 * Initialize MMKV with customize root folder.
 * @param context The context of Android App, usually from Application
 * @param rootDir The root folder of MMKV, defaults to $(FilesDir)/mmkv
 * @return The root folder of MMKV
 */
public static String initialize(Context context, String rootDir);

/**
 * Initialize MMKV with customize root folder and log level.
 * @param context The context of Android App, usually from Application
 * @param rootDir The root folder of MMKV
 * @param logLevel The log level of MMKV
 * @return The root folder of MMKV
 */
public static String initialize(Context context, String rootDir, MMKVLogLevel logLevel);

// Use custom directory on external storage
File customDir = new File(getExternalFilesDir(null), "custom_mmkv");
String rootDir = MMKV.initialize(this, customDir.getAbsolutePath());

/**
 * Initialize MMKV with a 3rd library loader.
 * @param context The context of Android App, usually from Application
 * @param loader The 3rd library loader (for example, the ReLinker)
 * @return The root folder of MMKV
 */
public static String initialize(Context context, LibLoader loader);

/**
 * Initialize MMKV with a 3rd library loader and customize log level.
 * @param context The context of Android App, usually from Application
 * @param loader The 3rd library loader
 * @param logLevel The log level of MMKV
 * @return The root folder of MMKV
 */
public static String initialize(Context context, LibLoader loader, MMKVLogLevel logLevel);

// Using ReLinker for safer native library loading
MMKV.LibLoader relinkerLoader = new MMKV.LibLoader() {
    @Override
    public void loadLibrary(String libName) {
        ReLinker.loadLibrary(MyApplication.this, libName);
    }
};
String rootDir = MMKV.initialize(this, relinkerLoader, MMKVLogLevel.LevelInfo);

/**
 * Initialize MMKV with customize settings.
 * @param context The context of Android App, usually from Application
 * @param rootDir The root folder of MMKV
 * @param loader The 3rd library loader (optional)
 * @param logLevel The log level of MMKV
 * @param handler The callback handler for error recovery and logging (optional)
 * @return The root folder of MMKV
 */
public static String initialize(Context context, String rootDir, LibLoader loader, MMKVLogLevel logLevel, MMKVHandler handler);

MMKVHandler customHandler = new MMKVHandler() {
    @Override
    public MMKVRecoverStrategic onMMKVCRCCheckFail(String mmapID) {
        Log.w("MMKV", "CRC check failed for " + mmapID);
        return MMKVRecoverStrategic.OnErrorRecover;
    }
    
    @Override
    public MMKVRecoverStrategic onMMKVFileLengthError(String mmapID) {
        Log.w("MMKV", "File length error for " + mmapID);
        return MMKVRecoverStrategic.OnErrorRecover;
    }
    
    @Override
    public boolean wantLogRedirecting() {
        return true; // Redirect MMKV logs to custom handler
    }
    
    @Override
    public void mmkvLog(MMKVLogLevel level, String file, int line, String function, String message) {
        Log.d("MMKV-Custom", message);
    }
};

String rootDir = MMKV.initialize(
    this,
    getFilesDir().getAbsolutePath() + "/mmkv",
    null,
    MMKVLogLevel.LevelInfo,
    customHandler
);

/**
 * Set the log level of MMKV.
 * @param level Defaults to MMKVLogLevel.LevelInfo
 */
public static void setLogLevel(MMKVLogLevel level);

/**
 * Get the root folder of MMKV.
 * @return The root folder of MMKV, defaults to $(FilesDir)/mmkv
 */
public static String getRootDir();

/**
 * Get the device's memory page size.
 * @return The device's memory page size
 */
public static int pageSize();

/**
 * Get the version of MMKV.
 * @return The version of MMKV
 */
public static String version();

/**
 * Notify MMKV that App is about to exit. It's totally fine not calling it at all.
 */
public static void onExit();

// Change log level at runtime
MMKV.setLogLevel(MMKVLogLevel.LevelDebug);

// Get version information
String version = MMKV.version();
Log.i("MMKV", "Using MMKV version: " + version);

// Get system page size
int pageSize = MMKV.pageSize();
Log.i("MMKV", "System page size: " + pageSize + " bytes");

// Cleanup on app exit (optional)
@Override
protected void onDestroy() {
    super.onDestroy();
    MMKV.onExit();
}

/**
 * Manually enable the process mode checker.
 * By default, it's automatically enabled in DEBUG build, and disabled in RELEASE build.
 */
public static void enableProcessModeChecker();

/**
 * Manually disable the process mode checker.
 * By default, it's automatically enabled in DEBUG build, and disabled in RELEASE build.
 */
public static void disableProcessModeChecker();

// Enable process mode checking in production for debugging
if (BuildConfig.DEBUG || isDebuggingMultiProcess) {
    MMKV.enableProcessModeChecker();
} else {
    MMKV.disableProcessModeChecker();
}

public interface LibLoader {
    void loadLibrary(String libName);
}

public interface MMKVHandler {
    MMKVRecoverStrategic onMMKVCRCCheckFail(String mmapID);
    MMKVRecoverStrategic onMMKVFileLengthError(String mmapID);
    boolean wantLogRedirecting();
    void mmkvLog(MMKVLogLevel level, String file, int line, String function, String message);
}

public enum MMKVLogLevel {
    LevelDebug,    // Debug level. Not available for release/production build
    LevelInfo,     // Info level. The default level
    LevelWarning,  // Warning level
    LevelError,    // Error level
    LevelNone      // Special level for disabling all logging
}

public enum MMKVRecoverStrategic {
    OnErrorDiscard,  // The default strategic is to discard everything on errors
    OnErrorRecover   // The recover strategic will try to recover as much data as possible
}