OKHttp通信使用（二）

以下代码摘自GitHub:https://github.com/square/okhttp/wiki/Recipes

设置缓存：

OKHTTP使用时通常会先设置缓存大小：

 private final OkHttpClient client;  public CacheResponse(File cacheDirectory) throws Exception {    int cacheSize = 10 * 1024 * 1024; // 10 MiB    Cache cache = new Cache(cacheDirectory, cacheSize);    client = new OkHttpClient.Builder()        .cache(cache)        .build();  }  public void run() throws Exception {    Request request = new Request.Builder()        .url("http://publicobject.com/helloworld.txt")        .build();    Response response1 = client.newCall(request).execute();    if (!response1.isSuccessful()) throw new IOException("Unexpected code " + response1);    String response1Body = response1.body().string();    System.out.println("Response 1 response:          " + response1);    System.out.println("Response 1 cache response:    " + response1.cacheResponse());    System.out.println("Response 1 network response:  " + response1.networkResponse());    Response response2 = client.newCall(request).execute();    if (!response2.isSuccessful()) throw new IOException("Unexpected code " + response2);    String response2Body = response2.body().string();    System.out.println("Response 2 response:          " + response2);    System.out.println("Response 2 cache response:    " + response2.cacheResponse());    System.out.println("Response 2 network response:  " + response2.networkResponse());    System.out.println("Response 2 equals Response 1? " + response1Body.equals(response2Body));  }

缓存的持续时间通常在请求头（Header中进行设置）che-Control: max-stale=3600

超时设置：

OKHTTP超时时间设置：

/** * Created by admin on 2016/6/14. */public class TimeOutClass {    private OkHttpClient client;    public void ConfigureTimeoutss() throws Exception {        client = new OkHttpClient.Builder()                .connectTimeout(3, TimeUnit.SECONDS)                .writeTimeout(3, TimeUnit.SECONDS)                .readTimeout(3, TimeUnit.SECONDS)                .build();    }    public void run() throws Exception {        Request request = new Request.Builder()                .url("http://httpbin.org/delay/2") // This URL is served with a 2 second delay.                .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 {                System.out.println("Response completed: " + response);            }        });    }}

取消请求：

取消一个请求设置：

public class CanclelingClass {    private final ScheduledExecutorService executor = Executors.newScheduledThreadPool(1);    private final OkHttpClient client = new OkHttpClient();    public void run() throws Exception {        Request request = new Request.Builder()                .url("http://httpbin.org/delay/2") // This URL is served with a 2 second delay.                .build();        final long startNanos = System.nanoTime();        final Call call = client.newCall(request);        // Schedule a job to cancel the call in 1 second.        executor.schedule(new Runnable() {            @Override            public void run() {                System.out.printf("%.2f Canceling call.%n", (System.nanoTime() - startNanos) / 1e9f);                call.cancel();                System.out.printf("%.2f Canceled call.%n", (System.nanoTime() - startNanos) / 1e9f);            }        }, 1, TimeUnit.SECONDS);        try {            System.out.printf("%.2f Executing call.%n", (System.nanoTime() - startNanos) / 1e9f);            Response response = call.execute();            System.out.printf("%.2f Call was expected to fail, but completed: %s%n",                    (System.nanoTime() - startNanos) / 1e9f, response);        } catch (IOException e) {            System.out.printf("%.2f Call failed as expected: %s%n",                    (System.nanoTime() - startNanos) / 1e9f, e);        }    }}

独立请求设置：

由于在一套程序中只能声明一个OkHttpClient()实例，如果要更改连接超时时间，或者其他参数可使用newBuilder进行设置。

/** * Created by admin on 2016/6/15. */public class PreRequestClass {    private final OkHttpClient client = new OkHttpClient();    public void run() throws Exception {        Request request = new Request.Builder()                .url("http://httpbin.org/delay/1") // This URL is served with a 1 second delay.                .build();        // Copy to customize OkHttp for this request.        OkHttpClient copy = client.newBuilder()                .readTimeout(5000, TimeUnit.MILLISECONDS)                .build();        copy.newCall(request).enqueue(new Callback() {            @Override            public void onFailure(Call call, IOException e) {            }            @Override            public void onResponse(Call call, Response response) throws IOException {                System.out.println("Response 1 succeeded: " + response);            }        });        OkHttpClient copy2 = client.newBuilder()                .readTimeout(3000, TimeUnit.MILLISECONDS)                .build();        copy2.newCall(request).enqueue(new Callback() {            @Override            public void onFailure(Call call, IOException e) {            }            @Override            public void onResponse(Call call, Response response) throws IOException {                System.out.println("Response 2 succeeded: " + response);            }        });    }}