Java tutorial
package android.support.v4.os; import android.os.Build.VERSION; import android.os.Environment; import android.util.Log; import java.io.File; import java.io.IOException; public class EnvironmentCompat { public static final String MEDIA_UNKNOWN = "unknown"; private static final String TAG = "EnvironmentCompat"; public static String getStorageState(File file) { if (VERSION.SDK_INT >= 19) { return EnvironmentCompatKitKat.getStorageState(file); } try { if (file.getCanonicalPath().startsWith(Environment.getExternalStorageDirectory().getCanonicalPath())) { return Environment.getExternalStorageState(); } } catch (IOException e) { Log.w(TAG, "Failed to resolve canonical path: " + e); } return MEDIA_UNKNOWN; } }