Simple File Downloader Library

A Sample Low Level Design of a file downloader library for Android with pause and resume support, following best pratices.

Major Highlights:

• Low Level Design of a File Downloader library having component like Download Request Builder, Request queue, Download Dispatcher , HttpClient and Download Task making Library higly customizable. -This downloader library has a simple interface to make download request.
• We can check if the status of downloading with the given download Id.
• The Library gives callbacks for everything like onProgress, onCancel, onStart, onError and etc while downloading a file.
• Supports proper request canceling
• Supports pause and resume while downloading a file.
• Supports Custom HttpClient for a Download Request.
• Followed best pratices
  • Builder Pattern:used to create Download Request Obj with few parameter compulsory & few are optional
  • Factory pattern: used to create Downloader obj
  • use of interface: to pass differrent implementation of future usecase scenarios

The Complete Library Folder Structure

├── Downloader
├── DownloadConfig
├── Downloader
├── httpclient
│   ├── DefaultHttpClient
│   ├── HttpClient
├── internals
│   ├── DownloadDispatcher
│   ├── DownloadRequest
│   ├── DownloadRequestQueue
│   └── DownloadTask
├── utils
│   ├── Utils