参考github项目XDroidMvp
想必Retrifit+Rxjava的使用，如今已经非常的普及了吧。在此介绍一种比较优雅的有关Retrifit+Rxjava封装的方法。
原本的步骤应该是这样，首先要创建OKHttpClient ，在其中添加一些拦截和超时处理，然后创建Retrofit对象并注入OKHttpClient对象，再获取接口实例Observable对象，然后绑定生命周期（防止内存泄漏）并订阅观察者Subscriber处理返回信息。
那现在应该如何封装，才能比较优雅，并且能够尽量的解耦呢？
- 1、提出Retrofits实现类，提供设置超时时间、添加拦截等处理的接口
首先应该将Retrofit这一块提出来，而创建Retrofit需要注入OKHttpClient，其中有很多与业务相关的处理，比如需要设置超时时间，拦截头部添加Header等等。那么这一块就可以写一个接口回调，在外部实现后注入。看一下这一块的代码吧
public class NetMgr {
private final long connectTimeoutMills = 10 * 1000L;
private final long readTimeoutMills = 10 * 1000L;
private NetProvider sProvider = null;
private static NetMgr instance;
private Map<String, NetProvider> providerMap = new HashMap<>();
private Map<String, Retrofit> retrofitMap = new HashMap<>();
private Map<String, OkHttpClient> clientMap = new HashMap<>();
public static NetMgr getInstance() {
if (instance == null) {
synchronized (NetMgr.class) {
if (instance == null) {
instance = new NetMgr();
}
}
}
return instance;
}
public <S> S get(String baseUrl, Class<S> service) {
return getInstance().getRetrofit(baseUrl).create(service);
}
public void registerProvider(NetProvider provider) {
this.sProvider = provider;
}
public void registerProvider(String baseUrl, NetProvider provider) {
getInstance().providerMap.put(baseUrl, provider);
}
public NetProvider getCommonProvider() {
return sProvider;
}
public void clearCache() {
getInstance().retrofitMap.clear();
getInstance().clientMap.clear();
}
public Retrofit getRetrofit(String baseUrl) {
return getRetrofit(baseUrl, null);
}
public Retrofit getRetrofit(String baseUrl, NetProvider provider) {
if (empty(baseUrl)) {
throw new IllegalStateException("baseUrl can not be null");
}
if (retrofitMap.get(baseUrl) != null) {
return retrofitMap.get(baseUrl);
}
if (provider == null) {
provider = providerMap.get(baseUrl);
if (provider == null) {
provider = sProvider;
}
}
checkProvider(provider);
Gson gson = new GsonBuilder()
.setDateFormat("yyyy-MM-dd HH:mm:ss")
.create();
Retrofit.Builder builder = new Retrofit.Builder()
.baseUrl(baseUrl)
.client(getClient(baseUrl, provider))
.addCallAdapterFactory(RxJavaCallAdapterFactory.create())
.addConverterFactory(GsonConverterFactory.create(gson));
Retrofit retrofit = builder.build();
retrofitMap.put(baseUrl, retrofit);
providerMap.put(baseUrl, provider);
return retrofit;
}
private boolean empty(String baseUrl) {
return baseUrl == null || baseUrl.isEmpty();
}
private OkHttpClient getClient(String baseUrl, NetProvider provider) {
if (empty(baseUrl)) {
throw new IllegalStateException("baseUrl can not be null");
}
if (clientMap.get(baseUrl) != null) {
return clientMap.get(baseUrl);
}
checkProvider(provider);
OkHttpClient.Builder builder = new OkHttpClient.Builder();
builder.connectTimeout(provider.configConnectTimeoutSecs() != 0
? provider.configConnectTimeoutSecs()
: connectTimeoutMills, TimeUnit.SECONDS);
builder.readTimeout(provider.configReadTimeoutSecs() != 0
? provider.configReadTimeoutSecs() : readTimeoutMills, TimeUnit.SECONDS);
builder.writeTimeout(provider.configWriteTimeoutSecs() != 0
? provider.configReadTimeoutSecs() : readTimeoutMills, TimeUnit.SECONDS);
CookieJar cookieJar = provider.configCookie();
if (cookieJar != null) {
builder.cookieJar(cookieJar);
}
provider.configHttps(builder);
RequestHandler handler = provider.configHandler();
if (handler != null) {
builder.addInterceptor(new NetInterceptor(handler));
}
Interceptor[] interceptors = provider.configInterceptors();
if (!empty(interceptors)) {
for (Interceptor interceptor : interceptors) {
builder.addInterceptor(interceptor);
}
}
if (provider.configLogEnable()) {
HttpLoggingInterceptor loggingInterceptor = new HttpLoggingInterceptor();
loggingInterceptor.setLevel(HttpLoggingInterceptor.Level.BODY);
builder.addInterceptor(loggingInterceptor);
}
OkHttpClient client = builder.build();
clientMap.put(baseUrl, client);
providerMap.put(baseUrl, provider);
return client;
}
private boolean empty(Interceptor[] interceptors) {
return interceptors == null || interceptors.length == 0;
}
private void checkProvider(NetProvider provider) {
if (provider == null) {
throw new IllegalStateException("must register provider first");
}
}
public Map<String, Retrofit> getRetrofitMap() {
return retrofitMap;
}
public Map<String, OkHttpClient> getClientMap() {
return clientMap;
}
}- 2、实现NetProvider接口并注入
NetMgr就是一个Retrofit的实现类，然后NetProvider是一个接口，需要在外部去实现，然后注入。再看一下NetProvider的实现类BaseNetProvider
public class BaseNetProvider implements NetProvider {
private static final long CONNECT_TIME_OUT = 30;
private static final long READ_TIME_OUT = 180;
private static final long WRITE_TIME_OUT = 30;
@Override
public Interceptor[] configInterceptors() {
return null;
}
@Override
public void configHttps(OkHttpClient.Builder builder) {
}
@Override
public CookieJar configCookie() {
return null;
}
@Override
public RequestHandler configHandler() {
return new HeaderHandler();
}
@Override
public long configConnectTimeoutSecs() {
return CONNECT_TIME_OUT;
}
@Override
public long configReadTimeoutSecs() {
return READ_TIME_OUT;
}
@Override
public long configWriteTimeoutSecs() {
return WRITE_TIME_OUT;
}
@Override
public boolean configLogEnable() {
return BuildConfig.DEBUG;
}
private class HeaderHandler implements RequestHandler {
@Override
public Request onBeforeRequest(Request request, Interceptor.Chain chain) {
return chain.request().newBuilder()
.addHeader("X-Auth-Token", Constant.accessToken)
.addHeader("Authorization", "")
.build();
}
@Override
public Response onAfterRequest(Response response, Interceptor.Chain chain)
throws IOException {
ApiException e = null;
if (401 == response.code()) {
throw new ApiException("登录已过期,请重新登录!");
} else if (403 == response.code()) {
throw new ApiException("禁止访问!");
} else if (404 == response.code()) {
throw new ApiException("链接错误");
} else if (503 == response.code()) {
throw new ApiException("服务器升级中!");
} else if (500 == response.code()) {
throw new ApiException("服务器内部错误!");
}
return response;
}
}在BaseNetProvider中实现了连接、读、写超时的时间处理，与请求和返回数据的请求头部处理。然后需要在Application中去注入BaseNetProvider
NetMgr.getInstance().registerProvider(new BaseNetProvider());
- 3、Observable实现
首先实现一个UseCase的基类，处理公共的使用方法。通过调用NetMgr.getInstance().getRetrofit(BuildConfig.BaseUrl).create(getType())来获取ApiService的实例，然后提供了指定线程的基类方法。至于PagingReq是一个分页模型，方便分页接口的使用。
public abstract class UseCase<T> {
//用于分页请求
protected PagingReq pagingReq = new PagingReq();
protected T ApiClient() {
return NetMgr.getInstance().getRetrofit(BuildConfig.BaseUrl).create(getType());
}
//指定观察者与被观察者线程
protected <T> Observable.Transformer<T, T> normalSchedulers() {
return new Observable.Transformer<T, T>() {
@Override
public Observable<T> call(Observable<T> source) {
return source.onTerminateDetach().subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread());
}
};
}
private Class<T> getType() {
Class<T> entityClass = null;
Type t = getClass().getGenericSuperclass();
Type[] p = ((ParameterizedType) t).getActualTypeArguments();
entityClass = (Class<T>) p[0];
return entityClass;
}
}此处实现一个简单的获取城市信息的接口。 首先定义接口ApiService，然后实现获取Observable的方法
public class GetCitiesCase extends UseCase<GetCitiesCase.Api> {
interface Api {
@GET("api/china/")
Observable<List<City>> getCitiesCase();
}
public Observable<List<City>> getCities() {
return ApiClient().getCitiesCase()
.compose(this.<List<City>>normalSchedulers());
}
}- 使用时调用
new GetCitiesCase().getCities()
.compose(this.<List<City>>bindToLifecycle())
.subscribe(new BaseSubscriber<List<City>>() {
@Override
public void onError(Throwable e) {
Toast.makeText(MainActivity.this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
@Override
public void onNext(List<City> o) {
getCitiesTv.setText("");
if (o != null && o.size() != 0) {
for (City city : o) {
getCitiesTv.setText(getCitiesTv.getText().toString() + city.id.intValue() + " " + city.name + "\n");
}
}
}
});调用就很简单了，只需绑定生命周期（防止内存泄漏），然后订阅Subscriber，处理成功或失败后的返回。