上海做网站比较有名的公司,郑州 互联网 公司网站,如何建立一个学校网站,沈阳公司做网站的本文主要应用了OkHttp的Interceptor来实现自定义重试次数
虽然OkHttp自带retryOnConnectionFailure(true)方法可以实现重试#xff0c;但是不支持自定义重试次数#xff0c;所以有时并不能满足我们的需求。
#1.自定义重试拦截器#xff1a; /*** 重试拦截器*/
public clas…本文主要应用了OkHttp的Interceptor来实现自定义重试次数
虽然OkHttp自带retryOnConnectionFailure(true)方法可以实现重试但是不支持自定义重试次数所以有时并不能满足我们的需求。
#1.自定义重试拦截器 /*** 重试拦截器*/
public class RetryIntercepter implements Interceptor {public int maxRetry;//最大重试次数private int retryNum 0;//假如设置为3次重试的话则最大可能请求4次默认1次 3次重试public RetryIntercepter(int maxRetry) {this.maxRetry maxRetry;}Overridepublic Response intercept(Chain chain) throws IOException {Request request chain.request();System.out.println(retryNum retryNum);Response response chain.proceed(request);while (!response.isSuccessful() retryNum maxRetry) {retryNum ;System.out.println(retryNum retryNum);response chain.proceed(request);}return response;}
} #2.测试场景类 1 public class RetryTest {2 String mUrl https://www.baidu.com/;3 OkHttpClient mClient;4 5 Before6 public void setUp() {7 HttpLoggingInterceptor logging new HttpLoggingInterceptor();8 logging.setLevel(HttpLoggingInterceptor.Level.BODY);9
10 mClient new OkHttpClient.Builder()
11 .addInterceptor(new RetryIntercepter(3))//重试
12 .addInterceptor(logging)//网络日志
13 .addInterceptor(new TestInterceptor())//模拟网络请求
14 .build();
15 }
16
17 Test
18 public void testRequest() throws IOException {
19 Request request new Request.Builder()
20 .url(mUrl)
21 .build();
22 Response response mClient.newCall(request).execute();
23 System.out.println(onResponse: response.body().string());
24 }
25
26 class TestInterceptor implements Interceptor {
27
28 Override
29 public Response intercept(Chain chain) throws IOException {
30 Request request chain.request();
31 String url request.url().toString();
32 System.out.println(url url);
33 Response response null;
34 if (url.equals(mUrl)) {
35 String responseString {\message\:\我是模拟的数据\};//模拟的错误的返回值
36 response new Response.Builder()
37 .code(400)
38 .request(request)
39 .protocol(Protocol.HTTP_1_0)
40 .body(ResponseBody.create(MediaType.parse(application/json), responseString.getBytes()))
41 .addHeader(content-type, application/json)
42 .build();
43 } else {
44 response chain.proceed(request);
45 }
46 return response;
47 }
48 }
49
50 } #3.输出结果 1 retryNum02 -- GET https://www.baidu.com/ HTTP/1.13 -- END GET4 urlhttps://www.baidu.com/5 -- 400 null https://www.baidu.com/ (13ms)6 content-type: application/json7 8 {message:我是模拟的数据}9 -- END HTTP (35-byte body)
10 retryNum1
11 -- GET https://www.baidu.com/ HTTP/1.1
12 -- END GET
13 urlhttps://www.baidu.com/
14 -- 400 null https://www.baidu.com/ (0ms)
15 content-type: application/json
16
17 {message:我是模拟的数据}
18 -- END HTTP (35-byte body)
19 retryNum2
20 -- GET https://www.baidu.com/ HTTP/1.1
21 -- END GET
22 urlhttps://www.baidu.com/
23 -- 400 null https://www.baidu.com/ (0ms)
24 content-type: application/json
25
26 {message:我是模拟的数据}
27 -- END HTTP (35-byte body)
28 retryNum3
29 -- GET https://www.baidu.com/ HTTP/1.1
30 -- END GET
31 urlhttps://www.baidu.com/
32 -- 400 null https://www.baidu.com/ (0ms)
33 content-type: application/json
34
35 {message:我是模拟的数据}
36 -- END HTTP (35-byte body)
37 onResponse:{message:我是模拟的数据} #4.结果分析1. 这里我用一个TestInterceptor拦截器拦截掉真实的网络请求实现response.code的自定义2. 在RetryIntercepter中通过response.isSuccessful()来对响应码进行判断循环调用了多次chain.proceed(request)来实现重试拦截3. 从输出中可以看到一共请求了4次默认1次 重试3次。
#5.其它实现方式如果你是使用OkHttp Retrofit RxJava你也可以使用retryWhen操作符retryWhen(new RetryWithDelay())来实现重试机制 1 public class RetryWithDelay implements Func1Observable? extends Throwable, Observable? {2 3 private final int maxRetries;4 private final int retryDelayMillis;5 private int retryCount;6 7 public RetryWithDelay(int maxRetries, int retryDelayMillis) {8 this.maxRetries maxRetries;9 this.retryDelayMillis retryDelayMillis;
10 }
11
12 Override
13 public Observable? call(Observable? extends Throwable attempts) {
14 return attempts
15 .flatMap(new Func1Throwable, Observable?() {
16 Override
17 public Observable? call(Throwable throwable) {
18 if ( retryCount maxRetries) {
19 // When this Observable calls onNext, the original Observable will be retried (i.e. re-subscribed).
20 LogUtil.print(get error, it will try after retryDelayMillis millisecond, retry count retryCount);
21 return Observable.timer(retryDelayMillis,
22 TimeUnit.MILLISECONDS);
23 }
24 // Max retries hit. Just pass the error along.
25 return Observable.error(throwable);
26 }
27 });
28 }
29 } 更多专业前端知识请上
【猿2048】www.mk2048.com
