android OkHttp3.0

OkHttp是一个高效的HTTP库:
1.支持 SPDY ，共享同一个Socket来处理同一个服务器的所有请求
2.如果SPDY不可用，则通过连接池来减少请求延时
3.无缝的支持GZIP来减少数据流量
4.缓存响应数据来减少重复的网络请求
优点：
OkHttp会从很多常用的连接问题中自动恢复。如果您的服务器配置了多个IP地址，当第一个IP连接失败的时候，会自动尝试下一个IP。OkHttp还处理了代理服务器问题和SSL握手失败问题。
使用 OkHttp 无需重写您程序中的网络代码。OkHttp实现了几乎和java.net.HttpURLConnection一样的API。如果您用了 Apache HttpClient，则OkHttp也提供了一个对应的okhttp-apache 模块
Okhttp的基本使用，从以下五方面讲解：

1、Get请求(同步和异步)
2、POST请求表单(key-value)
3、POST请求提交(JSON/String/文件等)（这个有待研究）
4、文件下载
5、请求超时设置

添加库依赖compile 'com.squareup.okhttp3:okhttp:3.4.1'compile 'com.github.franmontiel:PersistentCookieJar:v0.9.3'  // Cookies持久化库compile 'com.squareup.okhttp3:logging-interceptor:3.4.1'1、GET//同步GET请求OkHttpClient client = new OkHttpClient();String run(String url) throws IOException {  Request request = new Request.Builder().url(url).build();  Response response = client.newCall(request).execute();  return response.body().string();}//异步GET请求OkHttpClient client=new OkHttpClient();Request request = new Request.Builder().url(url).build();client.newCall(request).enqueue(new Callback() {  @Override  public void onFailure(Request request, IOException e) {}  @Override  public void onResponse(Response response) throws IOException {}});2、POSTpublic static final MediaType JSON = MediaType.parse("application/json; charset=utf-8");OkHttpClient client = new OkHttpClient();String post(String url, String json) throws IOException {  RequestBody body = RequestBody.create(JSON, json);  Request request = new Request.Builder()      .url(url)      .post(body)      .build();  Response response = client.newCall(request).execute();  return response.body().string();}3、异步调用使用enqueue方法，将call放入请求队列，然后okHttp会在线程池中进行网络访问OkHttpClient client = new OkHttpClient();Request request = new Request.Builder().url("https://github.com").build();client.newCall(request).enqueue(new Callback() {    @Override    public void onFailure(Call call, IOException e) {    }    @Override    public void onResponse(Call call, Response response) throws IOException {       Log.d("onResponse", "response.body(): "+response.body().string());    }});4、HTTP头部的设置和读取HTTP 头的数据结构是 Map> 类型。对于每个HTTP头，可能有多个值。但是大部分HTTP头都只有一个值，只有少部分HTTP头允许多个值。OkHttp的处理方式是：Request:header(name,value) 来设置HTTP头的唯一值addHeader(name,value) 来补充新值Response:header(name) 读取唯一值或多个值的最后一个值headers(name) 获取所有值//OkHttpClient client = new OkHttpClient();Request request = new Request.Builder()        .url("https://github.com")        .header("User-Agent", "super agent")        .addHeader("Accept", "text/html")        .build();Response response = client.newCall(request).execute();if (!response.isSuccessful()) {    throw new IOException("error: " + response);}System.out.println(response.header("Server"));System.out.println(response.headers("Set-Cookie"));5、表单提交RequestBody formBody = new FormEncodingBuilder()            .add("query", "Hello")            .build();6、文件上传指定 MultipartBuilder.FORM 类型并通过addPart方法添加不同的Part（每个Part由Header和RequestBody两部分组成），最后调用builde()方法构建一个RequestBody。MediaType MEDIA_TYPE_TEXT = MediaType.parse("text/plain");RequestBody requestBody = new MultipartBuilder()    .type(MultipartBuilder.FORM)    .addPart(            Headers.of("Content-Disposition", "form-data; name=\"title\""),            RequestBody.create(null, "input txt"))    .addPart(            Headers.of("Content-Disposition", "form-data; name=\"file\""),            RequestBody.create(MEDIA_TYPE_TEXT, new File("input.txt")))    .build();7、使用流的方式发送POST请求OkHttpClient client = new OkHttpClient();final MediaType MEDIA_TYPE_TEXT = MediaType.parse("text/plain");final String postBody = "Hello World";RequestBody requestBody = new RequestBody() {    @Override    public MediaType contentType() {        return MEDIA_TYPE_TEXT;    }    @Override    public void writeTo(BufferedSink sink) throws IOException {        sink.writeUtf8(postBody);    }    @Override    public long contentLength() throws IOException {        return postBody.length();    }};Request request = new Request.Builder()        .url("http://www.baidu.com")        .post(requestBody)        .build();Response response = client.newCall(request).execute();if (!response.isSuccessful()) {    throw new IOException("eror: " + response);}System.out.println(response.body().string());8、缓存控制CacheControlRequest request = new Request.Builder()    .cacheControl(new CacheControl.Builder().noCache().build()) // 强制不缓存    .url("http://publicobject.com/helloworld.txt")    .build();Request request = new Request.Builder()    .cacheControl(new CacheControl.Builder().maxAge(0, TimeUnit.SECONDS).build()) // 缓存策略由服务器指定    .url("http://publicobject.com/helloworld.txt")    .build();Request request = new Request.Builder()    .cacheControl(new CacheControl.Builder().onlyIfCached().build()) //强制缓存    .url("http://publicobject.com/helloworld.txt")    .build();Response forceCacheResponse = client.newCall(request).execute();if (forceCacheResponse.code() != 504) {  // The resource was cached! Show it.} else {  // The resource was not cached.}Request request = new Request.Builder()    .cacheControl(new CacheControl.Builder().maxStale(365, TimeUnit.DAYS).build()) // 允许使用旧的缓存    .url("http://publicobject.com/helloworld.txt")    .build();9、拦截器：可以监视，重写（重写请求、重写响应）和重试拦截器可以注册为应用拦截器和网络拦截器应用拦截器：不需要关心像重定向和重试这样的中间响应总是调用一次，即使HTTP响应从缓存中获取服务监视应用原始意图。不关心OkHttp注入的像If-None-Match头允许短路并不调用Chain.proceed()允许重试并执行多个Chain.proceed()调用网络拦截器：可以操作像重定向和重试这样的中间响应对于短路网络的缓存响应不会调用监视即将要通过网络传输的数据访问运输请求的Connection重写请求//重写响应private static final Interceptor interceptor = new Interceptor() {  @Override public Response intercept(Interceptor.Chain chain) throws IOException {    Response originalResponse = chain.proceed(chain.request());    return originalResponse.newBuilder()        .header("Cache-Control", "max-age=60")        .build();  }};OkHttpClient client = new OkHttpClient.Builder()              .addInterceptor(new HttpLoggingInterceptor() // 应用拦截器              .addNetworkInterceptor(interceptor) // 网络拦截器              .setLevel(HttpLoggingInterceptor.Level.BODY))              .build();           10、缓存设置File cacheDirectory = new File(getApplicationContext().getCacheDir().getAbsolutePath(), "Cache"); Cache cache = new Cache(cacheDirectory, 10 * 1024 * 1024)); // 创建缓存类OkHttpClient client = new OkHttpClient.Builder()      .retryOnConnectionFailure(true)      .connectTimeout(15, TimeUnit.SECONDS) // 连接超时设置      .readTimeout(10,TimeUnit.SECONDS); // 读超时设置      .writeTimeout(10,TimeUnit.SECONDS); // 写超时设置      .cache(cache) // 设置缓存，okhttp默认是没有缓存,且没有缓存目录的      .build();9、Cookies缓存：由CookieJar统一管理Cookies，只需要对OkHttpClient的cookieJar进行设置即可OkHttpClient mHttpClient = new OkHttpClient.Builder().cookieJar(new CookieJar() {    private final HashMap> cookieStore = new HashMap<>();    @Override    public void saveFromResponse(HttpUrl url, List cookies) {        cookieStore.put(url.host(), cookies);    }    @Override    public List loadForRequest(HttpUrl url) {        List cookies = cookieStore.get(url.host());        return cookies != null ? cookies : new ArrayList();    }}).build();10、Cookies持久化：PersistentCookieJarClearableCookieJar cookieJar = new PersistentCookieJar(new SetCookieCache(), new SharedPrefsCookiePersistor(context));OkHttpClient okHttpClient = new OkHttpClient.Builder()             .cookieJar(cookieJar)             .build();

android OkHttp3.0

更多相关文章

随机推荐