![](\"https:\/\/i.cdn.yimenapp.com\/2023-03\/31\/15\/12766754067.jpg\")
<\/figure>\n<\/p>\n.9.0′<\/p>\n
“`<\/p>\n
\u63a5\u4e0b\u6765\u5c31\u53ef\u4ee5\u521b\u5efa\u4e00\u4e2aRetrofit2\u7684\u5b9e\u4f8b\uff1a<\/p>\n
“`<\/p>\n
Retrofit retrofit = new Retrofit.Builder()<\/p>\n
.baseUrl(“http:\/\/www.xxx.com\/”)<\/p>\n
.addConverterFactory(GsonConverterFactory.create())<\/p>\n
.build();<\/p>\n
“`<\/p>\n
\u5176\u4e2d\uff0cbaseUrl()\u65b9\u6cd5\u7528\u4e8e\u8bbe\u7f6eAPI\u7684\u57fa\u7840URL\uff0caddConverterFactory()\u65b9\u6cd5\u7528\u4e8e\u8bbe\u7f6e\u6570\u636e\u89e3\u6790\u5668\u3002<\/p>\n
\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u5c31\u53ef\u4ee5\u521b\u5efa\u4e00\u4e2aAPI\u63a5\u53e3\uff1a<\/p>\n
“`<\/p>\n
public interface ApiService {<\/p>\n
@GET(“api\/user”)<\/p>\n
Call getUser(@Query(“id”) int id);<\/p>\n
}<\/p>\n
“`<\/p>\n
\u5176\u4e2d\uff0c@GET\u6ce8\u89e3\u7528\u4e8e\u8bbe\u7f6e\u8bf7\u6c42\u65b9\u5f0f\u548c\u8bf7\u6c42\u8def\u5f84\uff0c@Query\u6ce8\u89e3\u7528\u4e8e\u8bbe\u7f6e\u8bf7\u6c42\u53c2\u6570\u3002\u63a5\u7740\uff0c\u6211\u4eec\u5c31\u53ef\u4ee5\u4f7f\u7528Retrofit2\u8fdb\u884c\u7f51\u7edc\u8bf7\u6c42\uff1a<\/p>\n
“`<\/p>\n
ApiService apiService = retrofit.create(ApiService.class);<\/p>\n
Call call = apiService.getUser(1);<\/p>\n
call.enqueue(new Callback() {<\/p>\n
@Override<\/p>\n
public void onResponse(Call call, Response response) {<\/p>\n
User user = response.body();<\/p>\n
\/\/ \u5904\u7406\u8fd4\u56de\u7684\u6570\u636e<\/p>\n
}<\/p>\n
@Override<\/p>\n
public void onFailure(Call call, Throwable t) {<\/p>\n
\/\/ \u5904\u7406\u8bf7\u6c42\u5931\u8d25<\/p>\n
}<\/p>\n
});<\/p>\n
“`<\/p>\n
\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u901a\u8fc7retrofit.create()\u65b9\u6cd5\u521b\u5efa\u4e86\u4e00\u4e2aApiService\u63a5\u53e3\u7684\u5b9e\u4f8b\uff0c\u7136\u540e\u8c03\u7528getUser()\u65b9\u6cd5\u53d1\u8d77\u4e86\u4e00\u4e2a\u7f51\u7edc\u8bf7\u6c42\u3002\u5728\u8bf7\u6c42\u6210\u529f\u540e\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7response.body()\u65b9\u6cd5\u83b7\u53d6\u5230\u8fd4\u56de\u7684\u6570\u636e\uff0c\u7136\u540e\u8fdb\u884c\u5904\u7406\u3002<\/p>\n
\u4e8c\u3001Retrofit2\u7684\u5c01\u88c5<\/p>\n
\u5728\u5b9e\u9645\u5f00\u53d1\u4e2d\uff0c\u6211\u4eec\u901a\u5e38\u4f1a\u5bf9Retrofit2\u8fdb\u884c\u5c01\u88c5\uff0c\u4ee5\u65b9\u4fbf\u4f7f\u7528\u548c\u7ef4\u62a4\u3002\u4e0b\u9762\u5c31\u6765\u4ecb\u7ecd\u4e00\u4e0b\u5982\u4f55\u5bf9Retrofit2\u8fdb\u884c\u5c01\u88c5\u3002<\/p>\n
1. \u5c01\u88c5\u7f51\u7edc\u8bf7\u6c42<\/p>\n
\u6211\u4eec\u53ef\u4ee5\u5c06\u7f51\u7edc\u8bf7\u6c42\u7684\u4ee3\u7801\u5c01\u88c5\u5230\u4e00\u4e2a\u5355\u72ec\u7684\u7c7b\u4e2d\uff0c\u6bd4\u5982HttpManager\uff1a<\/p>\n
“`<\/p>\n
public class HttpManager {<\/p>\n
private Retrofit retrofit;<\/p>\n
private ApiService apiService;<\/p>\n
public HttpManager() {<\/p>\n
retrofit = new Retrofit.Builder()<\/p>\n
.baseUrl(“http:\/\/www.xxx.com\/”)<\/p>\n
.addConverterFactory(GsonConverterFactory.create())<\/p>\n
.build();<\/p>\n
apiService = retrofit.create(ApiService.class);<\/p>\n
}<\/p>\n
public void getUser(int id, Callback callback) {<\/p>\n
Call call = apiService.getUser(id);<\/p>\n
call.enqueue(callback);<\/p>\n
}<\/p>\n
}<\/p>\n
“`<\/p>\n
\u5728\u8fd9\u4e2a\u7c7b\u4e2d\uff0c\u6211\u4eec\u5c06Retrofit2\u7684\u5b9e\u4f8b\u548cApiService\u63a5\u53e3\u5c01\u88c5\u5728\u4e86\u4e00\u8d77\uff0c\u5e76\u4e14\u63d0\u4f9b\u4e86\u4e00\u4e2agetUser()\u65b9\u6cd5\u7528\u4e8e\u53d1\u8d77\u7f51\u7edc\u8bf7\u6c42\u3002\u5728\u8bf7\u6c42\u6210\u529f\u540e\uff0c\u6211\u4eec\u901a\u8fc7\u56de\u8c03\u7684\u65b9\u5f0f\u5c06\u6570\u636e\u8fd4\u56de\u7ed9\u8c03\u7528\u65b9\u3002<\/p>\n
2. \u5c01\u88c5\u6570\u636e\u89e3\u6790<\/p>\n
\u5728Retrofit2\u4e2d\uff0c\u6211\u4eec\u901a\u5e38\u4f1a\u4f7f\u7528Gson\u6765\u8fdb\u884c\u6570\u636e\u89e3\u6790\u3002\u6211\u4eec\u53ef\u4ee5\u5c06Gson\u7684\u89e3\u6790\u4ee3\u7801\u5c01\u88c5\u5230\u4e00\u4e2a\u5355\u72ec\u7684\u7c7b\u4e2d\uff0c\u6bd4\u5982JsonManager\uff1a<\/p>\n
“`<\/p>\n
public class JsonManager {<\/p>\n
private static Gson gson = new Gson();<\/p>\n
public static T fromJson(String json, Class clazz) {<\/p>\n
return gson.fromJson(json, clazz);<\/p>\n
}<\/p>\n
public static String toJson(T t) {<\/p>\n
return gson.toJson(t);<\/p>\n
}<\/p>\n
}<\/p>\n
“`<\/p>\n
\u5728\u8fd9\u4e2a\u7c7b\u4e2d\uff0c\u6211\u4eec\u5c06Gson\u7684\u89e3\u6790\u65b9\u6cd5\u5c01\u88c5\u4e86\u8d77\u6765\uff0c\u5e76\u4e14\u63d0\u4f9b\u4e86\u4e00\u4e2afromJson()\u65b9\u6cd5\u7528\u4e8e\u5c06JSON\u5b57\u7b26\u4e32\u8f6c\u6362\u6210Java\u5bf9\u8c61\uff0c\u63d0\u4f9b\u4e86\u4e00\u4e2atoJson()\u65b9\u6cd5\u7528\u4e8e\u5c06Java\u5bf9\u8c61\u8f6c\u6362\u6210JSON\u5b57\u7b26\u4e32\u3002<\/p>\n
3. \u5c01\u88c5\u9519\u8bef\u5904\u7406<\/p>\n
\u5728\u7f51\u7edc\u8bf7\u6c42\u4e2d\uff0c\u6211\u4eec\u901a\u5e38\u4f1a\u9047\u5230\u5404\u79cd\u9519\u8bef\uff0c\u6bd4\u5982\u7f51\u7edc\u5f02\u5e38\u3001\u670d\u52a1\u5668\u8fd4\u56de\u9519\u8bef\u7b49\u7b49\u3002\u6211\u4eec\u53ef\u4ee5\u5c06\u9519\u8bef\u5904\u7406\u7684\u4ee3\u7801\u5c01\u88c5\u5230\u4e00\u4e2a\u5355\u72ec\u7684\u7c7b\u4e2d\uff0c\u6bd4\u5982ErrorHandler\uff1a<\/p>\n
“`<\/p>\n
public class ErrorHandler {<\/p>\n
public static void handle(Throwable t) {<\/p>\n
if (t instanceof UnknownHostException) {<\/p>\n
\/\/ \u5904\u7406\u7f51\u7edc\u5f02\u5e38<\/p>\n
} else if (t instanceof HttpException) {<\/p>\n
\/\/ \u5904\u7406\u670d\u52a1\u5668\u8fd4\u56de\u9519\u8bef<\/p>\n
} else {<\/p>\n
\/\/ \u5904\u7406\u5176\u4ed6\u9519\u8bef<\/p>\n
}<\/p>\n
}<\/p>\n
}<\/p>\n
“`<\/p>\n
\u5728\u8fd9\u4e2a\u7c7b\u4e2d\uff0c\u6211\u4eec\u5c06\u9519\u8bef\u5904\u7406\u7684\u4ee3\u7801\u5c01\u88c5\u4e86\u8d77\u6765\uff0c\u5e76\u4e14\u63d0\u4f9b\u4e86\u4e00\u4e2ahandle()\u65b9\u6cd5\u7528\u4e8e\u5904\u7406\u5404\u79cd\u7c7b\u578b\u7684\u9519\u8bef\u3002<\/p>\n
4. \u5c01\u88c5\u7ed3\u679c\u5904\u7406<\/p>\n
\u5728\u7f51\u7edc\u8bf7\u6c42\u4e2d\uff0c\u6211\u4eec\u901a\u5e38\u9700\u8981\u5c06\u8bf7\u6c42\u7ed3\u679c\u8fd4\u56de\u7ed9\u8c03\u7528\u65b9\u3002\u6211\u4eec\u53ef\u4ee5\u5c06\u7ed3\u679c\u5904\u7406\u7684\u4ee3\u7801\u5c01\u88c5\u5230\u4e00\u4e2a\u5355\u72ec\u7684\u7c7b\u4e2d\uff0c\u6bd4\u5982ResultHandler\uff1a<\/p>\n
“`<\/p>\n
public class ResultHandler {<\/p>\n
public static void handle(Response response, Callback callback) {<\/p>\n
if (response.isSuccessful()) {<\/p>\n
T data = response.body();<\/p>\n
callback.onResponse(null, Response.success(data));<\/p>\n
} else {<\/p>\n
callback.onFailure(null, new HttpException(response));<\/p>\n
}<\/p>\n
}<\/p>\n
}<\/p>\n
“`<\/p>\n
\u5728\u8fd9\u4e2a\u7c7b\u4e2d\uff0c\u6211\u4eec\u5c06\u7ed3\u679c\u5904\u7406\u7684\u4ee3\u7801\u5c01\u88c5\u4e86\u8d77\u6765\uff0c\u5e76\u4e14\u63d0\u4f9b\u4e86\u4e00\u4e2ahandle()\u65b9\u6cd5\u7528\u4e8e\u5904\u7406\u8bf7\u6c42\u7ed3\u679c\u3002\u5728\u8bf7\u6c42\u6210\u529f\u65f6\uff0c\u6211\u4eec\u5c06\u8fd4\u56de\u7684\u6570\u636e\u901a\u8fc7callback.onResponse()\u65b9\u6cd5\u8fd4\u56de\u7ed9\u8c03\u7528\u65b9\uff1b\u5728\u8bf7\u6c42\u5931\u8d25\u65f6\uff0c\u6211\u4eec\u5c06\u5f02\u5e38\u901a\u8fc7callback.onFailure()\u65b9\u6cd5\u8fd4\u56de\u7ed9\u8c03\u7528\u65b9\u3002<\/p>\n
5. \u5c01\u88c5\u5b8c\u6574\u4ee3\u7801<\/p>\n
\u6700\u540e\uff0c\u6211\u4eec\u5c06\u4e0a\u8ff0\u5c01\u88c5\u4ee3\u7801\u6574\u5408\u5728\u4e00\u8d77\uff0c\u5f97\u5230\u4e00\u4e2a\u5b8c\u6574\u7684\u5c01\u88c5\u7c7b\uff1a<\/p>\n
“`<\/p>\n
public class HttpManager {<\/p>\n
private Retrofit retrofit;<\/p>\n
private ApiService apiService;<\/p>\n
public HttpManager() {<\/p>\n
retrofit = new Retrofit.Builder()<\/p>\n
.baseUrl(“http:\/\/www.xxx.com\/”)<\/p>\n
.addConverterFactory(GsonConverterFactory.create())<\/p>\n
.build();<\/p>\n
apiService = retrofit.create(ApiService.class);<\/p>\n
}<\/p>\n
public void getUser(int id, Callback callback) {<\/p>\n
Call call = apiService.getUser(id);<\/p>\n
call.enqueue(new Callback() {<\/p>\n
@Override<\/p>\n