Java tutorial
//package com.java2s; import android.app.Activity; import android.content.Context; import android.os.storage.StorageManager; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; public class Main { public static boolean hasExtSdcard(Context context) { String[] paths; StorageManager service = (StorageManager) context.getSystemService(Activity.STORAGE_SERVICE); try { Method mMethod = service.getClass().getMethod("getVolumePaths"); paths = (String[]) mMethod.invoke(service); } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } return false; } }