1-3.Retrofit 异常请求清单（404 请求、超时请求、连接失败请求）
Retrofit
1、Retrofit 概述
- Retrofit 是一个网络请求库，专门用于发送 HTTP 请求和处理 HTTP 响应
2、Retrofit 引入
- 在 AndroidManifest.xml 文件中添加相关权限，如果是 Android 6.0（API 级别 23）或之后，需要在运行时请求
<uses-permission android:name="android.permission.INTERNET" />
- 在模块级
build.gradle中引入相关依赖
implementation 'com.squareup.okhttp3:logging-interceptor:3.8.1'implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.squareup.retrofit2:converter-scalars:2.9.0'implementation 'com.squareup.retrofit2:adapter-rxjava:2.1.0'
implementation 'io.reactivex:rxandroid:1.2.0'
3、Retrofit 使用步骤
-
创建接口：创建一个接口，并定义具体的请求方法，使用 Retrofit 提供的注解来描述 HTTP 请求
-
配置 Retrofit：使用
Retrofit.Builder构建出一个 Retrofit 实例对象 -
创建接口代理对象：通过 Retrofit 实例对象创建接口的代理对象
-
发送并处理请求：调用接口方法发送网络请求，通过回调处理请求结果
一、404 请求
1、Client Api
- ApiService.java
@GET("test/testGet12345")
Call<String> test404();
2、Client Test
- MainActivity.java
// 日志拦截器
HttpLoggingInterceptor httpLoggingInterceptor = new HttpLoggingInterceptor();
httpLoggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);OkHttpClient.Builder okHttpClientBuilder = new OkHttpClient.Builder();
okHttpClientBuilder.addInterceptor(httpLoggingInterceptor);
OkHttpClient okHttpClient = okHttpClientBuilder.build();// 构建 Retrofit 对象
Retrofit retrofit = new Retrofit.Builder().baseUrl("http://172.31.8.3:9999").client(okHttpClient).addConverterFactory(ScalarsConverterFactory.create()).addConverterFactory(GsonConverterFactory.create()) // 解析实体类.addCallAdapterFactory(RxJavaCallAdapterFactory.create()) // 结合 RxJava.build();ApiService apiService = retrofit.create(ApiService.class);
apiService.test404().enqueue(new Callback<String>() {@Overridepublic void onResponse(Call<String> call, Response<String> response) {if (response.code() == 200) {String result = response.body();Log.i(TAG, "------------------------------ 请求成功，结果为：" + result);return;}if (response.code() == 404) {Log.i(TAG, "------------------------------ 请求 404");return;}Log.i(TAG, "------------------------------ 请求失败");}@Overridepublic void onFailure(Call<String> call, Throwable t) {Log.i(TAG, "------------------------------ 请求失败：" + t.getMessage());Log.i(TAG, "------------------------------ " + t.getClass().getName());}
});
- 输出结果
D/OkHttp: --> GET http://192.168.0.10:9999/test/testGet12345 http/1.1
D/OkHttp: --> END GETD/OkHttp: <-- 404 http://192.168.0.10:9999/test/testGet12345 (101ms)
D/OkHttp: Content-Type: application/json
D/OkHttp: Transfer-Encoding: chunked
D/OkHttp: Date: Wed, 16 Oct 2024 13:01:13 GMT
D/OkHttp: Keep-Alive: timeout=60
D/OkHttp: Connection: keep-alive
D/OkHttp: {"timestamp":"2024-10-16T13:01:13.422+00:00","status":404,"error":"Not Found","path":"/test/testGet12345"}
D/OkHttp: <-- END HTTP (106-byte body)I/MainActivity: ------------------------------ 请求 404
二、超时请求
1、Server
- TestController.java
@RestController
@RequestMapping("/test")
@CrossOrigin
public class TestController {@GetMapping("/testTimeout")public String testTimeout() {try {Thread.sleep(20 * 1000);} catch (InterruptedException e) {e.printStackTrace();}return "testTimeout Hello World";}
}
2、Client Api
- ApiService.java
@GET("/test/testTimeout")
Call<String> testTimeout();
3、Client Test
- MainActivity.java
// 日志拦截器
HttpLoggingInterceptor httpLoggingInterceptor = new HttpLoggingInterceptor();
httpLoggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);OkHttpClient.Builder okHttpClientBuilder = new OkHttpClient.Builder();
okHttpClientBuilder.addInterceptor(httpLoggingInterceptor);
okHttpClientBuilder.connectTimeout(10, TimeUnit.SECONDS); // 连接超时
okHttpClientBuilder.readTimeout(10, TimeUnit.SECONDS); // 读取超时
okHttpClientBuilder.writeTimeout(10, TimeUnit.SECONDS); // 写入超时
OkHttpClient okHttpClient = okHttpClientBuilder.build();// 构建 Retrofit 对象
Retrofit retrofit = new Retrofit.Builder().baseUrl("http://172.31.8.3:9999").client(okHttpClient).addConverterFactory(ScalarsConverterFactory.create()).addConverterFactory(GsonConverterFactory.create()) // 解析实体类.addCallAdapterFactory(RxJavaCallAdapterFactory.create()) // 结合 RxJava.build();apiService = retrofit.create(ApiService.class);
apiService.testTimeout().enqueue(new Callback<String>() {@Overridepublic void onResponse(Call<String> call, Response<String> response) {String result = response.body();Log.i(TAG, "------------------------------ 请求成功，结果为：" + result);}@Overridepublic void onFailure(Call<String> call, Throwable t) {Log.i(TAG, "------------------------------ 请求失败：" + t.getMessage());Log.i(TAG, "------------------------------ " + t.getClass().getName());}
});
- 输出结果
D/OkHttp: --> GET http://192.168.0.10:9999/test/testTimeout http/1.1
D/OkHttp: --> END GETD/OkHttp: <-- HTTP FAILED: java.net.SocketTimeoutException: timeoutI/Main2Activity: ------------------------------ 请求失败：timeout
I/Main2Activity: ------------------------------ java.net.SocketTimeoutException
三、连接失败请求（错误地址）
1、Client Api
- ApiService.java
@GET("/test/testGet")
Call<String> testFailedToConnect();
2、Client Test
- MainActivity.java
// 日志拦截器
HttpLoggingInterceptor httpLoggingInterceptor = new HttpLoggingInterceptor();
httpLoggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);OkHttpClient.Builder okHttpClientBuilder = new OkHttpClient.Builder();
okHttpClientBuilder.addInterceptor(httpLoggingInterceptor);
OkHttpClient okHttpClient = okHttpClientBuilder.build();// 构建 Retrofit 对象
Retrofit retrofit = new Retrofit.Builder().baseUrl("http://192.168.0.11:9999").client(okHttpClient).addConverterFactory(ScalarsConverterFactory.create()).addConverterFactory(GsonConverterFactory.create()) // 解析实体类.addCallAdapterFactory(RxJavaCallAdapterFactory.create()) // 结合 RxJava.build();ApiService apiService = retrofit.create(ApiService.class);
apiService.testFailedToConnect().enqueue(new Callback<String>() {@Overridepublic void onResponse(Call<String> call, Response<String> response) {String result = response.body();Log.i(TAG, "------------------------------ 请求成功，结果为：" + result);}@Overridepublic void onFailure(Call<String> call, Throwable t) {Log.i(TAG, "------------------------------ 请求失败：" + t.getMessage());Log.i(TAG, "------------------------------ " + t.getClass().getName());}
});
- 输出结果
D/OkHttp: --> GET http://192.168.0.11:9999/test/testGet http/1.1
D/OkHttp: --> END GET