cachingarraylistobject.java

To Write a ArrayList<File>:

public static void createCachedFile (Context context, String key, ArrayList<File> fileName) throws IOException {

        String tempFile = null;
        for (File file : fileName) {
            FileOutputStream fos = context.openFileOutput (key, Context.MODE_PRIVATE);
            ObjectOutputStream oos = new ObjectOutputStream (fos);
            oos.writeObject (fileName);
            oos.close ();
            fos.close ();

        }
    }
    
To Read a ArrayList<File>

public static Object readCachedFile (Context context, String key) throws IOException, ClassNotFoundException {
        FileInputStream fis = context.openFileInput (key);
        ObjectInputStream ois = new ObjectInputStream (fis);
        Object object = ois.readObject ();
        return object;
    }

    
Final code in my Activity

        createCachedFile (MainActivity.this,"apk",adapter.getAppList ());
        ArrayList<File> apkCacheList = (ArrayList<File>)readCachedFile  (MainActivity.this, "apk");