求推荐支持JSON请求、文件下载与缓存的Android HTTP请求库

Hey there! I totally get the frustration of having to build every piece (including file caching) from scratch with Volley. Let me share some solid Android HTTP libraries that check all your requirements perfectly:

1. Retrofit + OkHttp (Most Popular & Flexible) #

This combo is the go-to for most Android devs, and it’s perfect for your needs:

• JSON Requests: Retrofit plays nicely with converters like GsonConverterFactory to auto-parse JSON responses into your model classes—no manual string parsing required. Super clean and maintainable.
• File Download: You can define download endpoints that return ResponseBody, then write the stream directly to a file on disk. It’s straightforward to add progress callbacks too if you need them.
• Caching Control: This is where OkHttp shines. You can set up a cache and custom interceptors to split behavior between JSON and file requests:
  • For JSON responses: Add a Cache-Control: no-store, no-cache header to ensure nothing gets cached.
  • For file downloads: Set a max-age value (e.g., Cache-Control: max-age=86400 for 1 day) to enforce timed caching. OkHttp even handles automatic cache eviction when the cache size hits your limit.

Here’s a quick snippet to show the cache setup:

// Configure cache size and directory
val cacheSize = 10 * 1024 * 1024 // 10 MB
val cache = Cache(context.cacheDir, cacheSize)

// Build OkHttpClient with custom interceptor
val okHttpClient = OkHttpClient.Builder()
    .cache(cache)
    .addInterceptor { chain ->
        val originalRequest = chain.request()
        val modifiedRequest = when {
            // Check if this is a file download request (adjust the URL pattern as needed)
            originalRequest.url.toString().contains("/downloads/") -> {
                originalRequest.newBuilder()
                    .header("Cache-Control", "max-age=86400") // Cache for 1 day
                    .build()
            }
            else -> {
                // Disable cache for all other (JSON) requests
                originalRequest.newBuilder()
                    .header("Cache-Control", "no-store")
                    .build()
            }
        }
        chain.proceed(modifiedRequest)
    }
    .build()

// Set up Retrofit with the configured OkHttpClient
val retrofit = Retrofit.Builder()
    .baseUrl("YOUR_BASE_API_URL")
    .client(okHttpClient)
    .addConverterFactory(GsonConverterFactory.create())
    .build()

2. OkHttp (Standalone, Lightweight) #

If you don’t want the annotation-based structure of Retrofit, OkHttp alone can handle everything you need:

• JSON Requests: Send GET/POST requests, then parse the response string using Gson or Moshi manually. It’s a bit more hands-on but gives you full control.
• File Download: Use ResponseBody to write the input stream to your target file—easy to implement with basic I/O operations.
• Caching: Same as the Retrofit combo—configure the cache and interceptors to apply different rules to JSON vs file requests.

3. FastAndroidNetworking (Simplified API) #

Built on top of OkHttp, this library offers a more concise API for common Android networking tasks:

• JSON Support: Built-in JSON parsing, with options to get raw JSON objects/arrays or map responses directly to model classes.
• File Download: One-line methods to download files to a specified path, with built-in progress callbacks for tracking download status.
• Caching: You can set cache policies per request—disable caching for JSON calls with setCacheEnabled(false), and set a cache expiry time for file downloads using setCacheDuration().

Quick Tips: #

• All these libraries handle background threading properly, so you won’t run into ANR issues from doing network ops on the UI thread.
• For file caching, always keep an eye on the cache size to avoid eating up too much of the user’s storage—OkHttp’s automatic eviction is a huge help here.

内容的提问来源于stack exchange，提问作者kklmarvelmedia