背景
目前，Google對HttpClient的摒棄，雖然之前一段時間volley的得到一定的關注，但是後來關注度逐漸的降低，但是Retrofit的依然是各大的Android開發者使用作為網絡請求的架構，而且retrofit對okhttp進行了很好的依賴。
Retrofit是由square公司開發的。square在github上釋出了很多優秀的Android開源項目。例如:otto(事件總線),leakcanary(排查記憶體洩露),android-times-square(月曆控件),dagger(依賴注入),picasso(異步加載圖檔),okhttp(網絡請求),retrofit(網絡請求)等等。更多square上的開源項目我們可以去square的GitHub進行檢視。這次就來介紹一下retrofit的一些基本用法。retrofit是REST安卓用戶端請求庫。使用retrofit可以進行GET，POST，PUT，DELETE等請求方式
使用
1、加入依賴
compile 'com.squareup.retrofit2:retrofit:2.1.0'
compile 'com.squareup.retrofit2:converter-gson:2.1.0'
compile 'com.squareup.retrofit2:adapter-rxjava:2.1.0'
compile 'io.reactivex:rxjava:1.2.4'
compile 'io.reactivex:rxandroid:1.2.1'
compile 'org.ligboy.retrofit2:converter-fastjson-android:2.1.0'
這些依賴中有對RxJava RxAndroid等的依賴。
注解的說明
retrofit通過使用注解來簡化請求，大體分為以下幾類：
1.用于标注請求方式的注解
2.用于标記請求頭的注解
3.用于标記請求參數的注解
4.用于标記請求和響應格式的注解
請求方法注解
| 注解 | 說明 |
|---|---|
| @GET | get請求 |
| @POST | post請求 |
| @PUT | put請求 |
| @DELETE | delete請求 |
| @PATCH | patch請求，該請求是對put請求的補充，用于更新局部資源 |
| @HEAD | head請求 |
| @OPTIONS | option請求 |
| @HTTP | 通用注解,可以替換以上所有的注解，其擁有三個屬性：method，path，hasBody |
請求頭注解
| 注解 | 說明 |
|---|---|
| @Headers | 用于添加強定請求頭，可以同時添加多個。通過該注解添加的請求頭不會互相覆寫，而是共同存在 |
| @Header | 作為方法的參數傳入，用于添加不固定值的Header，該注解會更新已有的請求頭 |
請求參數注解
| 名稱 | 說明 |
|---|---|
| @Body | 多用于post請求發送非表單資料,比如想要以post方式傳遞json格式資料 |
| @Filed | 多用于post請求中表單字段,Filed和FieldMap需要FormUrlEncoded結合使用 |
| @FiledMap | 和@Filed作用一緻，用于不确定表單參數 |
| @Part | 用于表單字段,Part和PartMap與Multipart注解結合使用,适合檔案上傳的情況 |
| @PartMap | 用于表單字段,預設接受的類型是Map<String,REquestBody>，可用于實作多檔案上傳 |
| @Path | 用于url中的占位符 |
| @Query | 用于Get中指定參數 |
| @QueryMap | 和Query使用類似 |
| @Url | 指定請求路徑 |
請求和響應格式注解
| 名稱 | 說明 |
|---|---|
| @FormUrlEncoded | 表示請求發送編碼表單資料，每個鍵值對需要使用@Field注解 |
| @Multipart | 表示請求發送multipart資料，需要配合使用@Part |
| @Streaming | 表示響應用位元組流的形式傳回.如果沒使用該注解,預設會把資料全部載入到記憶體中.該注解在在下載下傳大檔案的特别有用 |
下面是官網上的Api的說明：
API Declaration
Annotations on the interface methods and its parameters indicate how a request will be handled.
REQUEST METHOD
Every method must have an HTTP annotation that provides the request method and relative URL. There are five built-in annotations:
GET
,
POST
,
PUT
,
DELETE
, and
HEAD
. The relative URL of the resource is specified in the annotation.
@GET("users/list") You can also specify query parameters in the URL.
@GET("users/list?sort=desc") URL MANIPULATION
A request URL can be updated dynamically using replacement blocks and parameters on the method. A replacement block is an alphanumeric string surrounded by
{
and
}
. A corresponding parameter must be annotated with
@Path
using the same string.
@GET("group/{id}/users")
Call<List<User>> groupList(@Path("id") int groupId); Query parameters can also be added.
@GET("group/{id}/users")
Call<List<User>> groupList(@Path("id") int groupId, @Query("sort") String sort); For complex query parameter combinations a
Map
can be used.
@GET("group/{id}/users")
Call<List<User>> groupList(@Path("id") int groupId, @QueryMap Map<String, String> options); REQUEST BODY
An object can be specified for use as an HTTP request body with the
@Body
annotation.
@POST("users/new")
Call<User> createUser(@Body User user); The object will also be converted using a converter specified on the
Retrofit
instance. If no converter is added, only
RequestBody
can be used.
FORM ENCODED AND MULTIPART
Methods can also be declared to send form-encoded and multipart data.
Form-encoded data is sent when
@FormUrlEncoded
is present on the method. Each key-value pair is annotated with
@Field
containing the name and the object providing the value.
@FormUrlEncoded
@POST("user/edit")
Call<User> updateUser(@Field("first_name") String first, @Field("last_name") String last); Multipart requests are used when
@Multipart
is present on the method. Parts are declared using the
@Part
annotation.
@Multipart
@PUT("user/photo")
Call<User> updateUser(@Part("photo") RequestBody photo, @Part("description") RequestBody description); Multipart parts use one of
Retrofit
's converters or they can implement
RequestBody
to handle their own serialization.
HEADER MANIPULATION
You can set static headers for a method using the
@Headers
annotation.
@Headers("Cache-Control: max-age=640000")
@GET("widget/list")
Call<List<Widget>> widgetList(); @Headers({
"Accept: application/vnd.github.v3.full+json",
"User-Agent: Retrofit-Sample-App"
})
@GET("users/{username}")
Call<User> getUser(@Path("username") String username); Note that headers do not overwrite each other. All headers with the same name will be included in the request.
A request Header can be updated dynamically using the
@Header
annotation. A corresponding parameter must be provided to the
@Header
. If the value is null, the header will be omitted. Otherwise,
toString
will be called on the value, and the result used.
@GET("user")
Call<User> getUser(@Header("Authorization") String authorization) 下面是我對Retrofit的進行初始化
Interceptor headerInterceptor = new Interceptor() {
@Override
public Response intercept(Chain chain) throws IOException {
Request original = chain.request().newBuilder()
.addHeader("Accept", "application/json")
.method(chain.request().method(), chain.request().body())
.build();
return chain.proceed(original);
}
};
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(headerInterceptor)
.connectTimeout(10000L, TimeUnit.MILLISECONDS)
.readTimeout(10000L, TimeUnit.MILLISECONDS)
.sslSocketFactory(BaseApplication.sslParams.sSLSocketFactory, BaseApplication.sslParams.trustManager)
.hostnameVerifier(new HostnameVerifier() {
@Override
public boolean verify(String s, SSLSession sslSession) {
return true;
}
})
.build();
jsonInstance = new Retrofit.Builder()
.client(client)
.baseUrl(Constants.APP_HOST)
.addConverterFactory(GsonConverterFactory.create())
.addCallAdapterFactory(RxJava2CallAdapterFactory.create())
.build();
return jsonInstance;
這裡面有對攔截器的添加，可以根據自己的需要進行自行的添加，逾時的設定也可以自行的設定。
因為我的項目中，需要添加Https的請求，是以我的有ssl的證書添加設定。等下會在後面的部分進行說明和使用方法的介紹。
@POST("users/companyLogin")
Observable<LoginResponse> getLoginResponse(@Body LoginRequest request);
我這邊是運用了Observable不是Call，感覺Call的回調有些麻煩，這裡用到了RxJava進行處理
下面是請求結果的處理
Retrofit retrofit = RetrofitInstance.getJsonInstance();
LoginService service = retrofit.create(LoginService.class);
service.getLoginResponse(loginRequest)
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Observer<LoginResponse>() {
@Override
public void onSubscribe(Disposable d) {
}
@Override
public void onNext(LoginResponse value) {
listener.OnSuccess(value);
}
@Override
public void onError(Throwable e) {
listener.OnFailure(e);
}
@Override
public void onComplete() {
}
});
這已經是retrofit的一個基本的操作流程了。
項目中經常回用到上傳使用，下面在簡要的說明一下具體的方法：
上傳：
public class RetrofitMutiPartTool {
//Mutipart的String直接傳會多一對引号，必須轉成Requestbody才行
public static RequestBody toRequestBody(String value) {
return RequestBody.create(MediaType.parse("text/plain"), value);
}
public static RequestBody toRequestBody(File value) {
RequestBody body = RequestBody.create(MediaType.parse("multipart/form-data"), value);
return body;
}
public static RequestBody toRequestBody(byte[] value) {
RequestBody body = RequestBody.create(MediaType.parse("multipart/form-data"), value);
return body;
}
} private MultipartBody.Part Front(String path) {
if (path != null) {
file1 = new File(path);
RequestBody fileBody1 = RetrofitMutiPartTool.toRequestBody(file1);
MultipartBody.Part uploadFile1 = MultipartBody.Part.createFormData("uploadFile1", file1.getName(), fileBody1);
return uploadFile1;
} else {
return null;
} 請求的接口如下
@Multipart
@POST(ProductURL.User_addIdentityInfo)
Observable<AddIdentityInfoResponse> addIdentityInfor(@Part MultipartBody.Part uploadFile1,
@Part MultipartBody.Part uploadFile2,
@Part MultipartBody.Part uploadBiometric,
@Query("uid") long uid,
@Query("name") String name,
@Query("mobile") String mobile,
@Query("gender") String gender,
@Query("birthday") String birthday,
@Query("certAddress") String certAddress,
@Query("certType") int certType,
@Query("certNo") String certNo); 下面介紹的是使用https
public class HttpsUtils {
public static class SSLParams {
public SSLSocketFactory sSLSocketFactory;
public X509TrustManager trustManager;
}
public static SSLParams getSslSocketFactory(InputStream[] certificates, InputStream bksFile, String password) {
SSLParams sslParams = new SSLParams();
try {
TrustManager[] trustManagers = prepareTrustManager(certificates);
KeyManager[] keyManagers = prepareKeyManager(bksFile, password);
SSLContext sslContext = SSLContext.getInstance("TLS");
X509TrustManager trustManager = null;
//這裡使用證書的時候要進行的驗證，如果失敗的話可以直接走trustManager = new UnSafeTrustManager();
if (trustManagers != null) {
// trustManager = new MyTrustManager(chooseTrustManager(trustManagers));
// } else {
// trustManager = new UnSafeTrustManager();
// }
trustManager = new UnSafeTrustManager();
sslContext.init(keyManagers, new TrustManager[]{trustManager}, null);
sslParams.sSLSocketFactory = sslContext.getSocketFactory();
sslParams.trustManager = trustManager;
return sslParams;
} catch (NoSuchAlgorithmException e) {
throw new AssertionError(e);
} catch (KeyManagementException e) {
throw new AssertionError(e);
}
// catch (KeyStoreException e) {
// throw new AssertionError(e);
// }
}
private class UnSafeHostnameVerifier implements HostnameVerifier {
@Override
public boolean verify(String hostname, SSLSession session) {
return true;
}
}
private static class UnSafeTrustManager implements X509TrustManager {
@Override
public void checkClientTrusted(X509Certificate[] chain, String authType)
throws CertificateException {
}
@Override
public void checkServerTrusted(X509Certificate[] chain, String authType)
throws CertificateException {
}
@Override
public X509Certificate[] getAcceptedIssuers() {
return new X509Certificate[]{};
}
}
private static TrustManager[] prepareTrustManager(InputStream... certificates) {
if (certificates == null || certificates.length <= 0) return null;
try {
CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
KeyStore keyStore = KeyStore.getInstance(KeyStore.getDefaultType());
keyStore.load(null);
int index = 0;
for (InputStream certificate : certificates) {
String certificateAlias = Integer.toString(index++);
keyStore.setCertificateEntry(certificateAlias, certificateFactory.generateCertificate(certificate));
try {
if (certificate != null)
certificate.close();
} catch (IOException e)
{
}
}
TrustManagerFactory trustManagerFactory = null;
trustManagerFactory = TrustManagerFactory.
getInstance(TrustManagerFactory.getDefaultAlgorithm());
trustManagerFactory.init(keyStore);
TrustManager[] trustManagers = trustManagerFactory.getTrustManagers();
return trustManagers;
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (CertificateException e) {
e.printStackTrace();
} catch (KeyStoreException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private static KeyManager[] prepareKeyManager(InputStream bksFile, String password) {
try {
if (bksFile == null || password == null) return null;
KeyStore clientKeyStore = KeyStore.getInstance("BKS");
clientKeyStore.load(bksFile, password.toCharArray());
KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
keyManagerFactory.init(clientKeyStore, password.toCharArray());
return keyManagerFactory.getKeyManagers();
} catch (KeyStoreException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (UnrecoverableKeyException e) {
e.printStackTrace();
} catch (CertificateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
private static X509TrustManager chooseTrustManager(TrustManager[] trustManagers) {
for (TrustManager trustManager : trustManagers) {
if (trustManager instanceof X509TrustManager) {
return (X509TrustManager) trustManager;
}
}
return null;
}
private static class MyTrustManager implements X509TrustManager {
private X509TrustManager defaultTrustManager;
private X509TrustManager localTrustManager;
public MyTrustManager(X509TrustManager localTrustManager) throws NoSuchAlgorithmException, KeyStoreException {
TrustManagerFactory var4 = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
var4.init((KeyStore) null);
defaultTrustManager = chooseTrustManager(var4.getTrustManagers());
this.localTrustManager = localTrustManager;
}
@Override
public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {
}
@Override
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {
try {
defaultTrustManager.checkServerTrusted(chain, authType);
} catch (CertificateException ce) {
localTrustManager.checkServerTrusted(chain, authType);
}
}
@Override
public X509Certificate[] getAcceptedIssuers() {
return new X509Certificate[0];
}
}
}
HttpsUtils.SSLParams sslParams = HttpsUtils.getSslSocketFactory(null, null, null); sslParams是在Application oncreate的時候擷取，然後在Retrofit 初始化的時候添加上去
OkHttpClient client = new OkHttpClient.Builder()
.addInterceptor(headerInterceptor)
.connectTimeout(10000L, TimeUnit.MILLISECONDS)
.readTimeout(10000L, TimeUnit.MILLISECONDS)
.sslSocketFactory(BaseApplication.sslParams.sSLSocketFactory, BaseApplication.sslParams.trustManager)
.hostnameVerifier(new HostnameVerifier() {
@Override
public boolean verify(String s, SSLSession sslSession) {
return true;
}
})
.build(); 這些都是在項目中用到的，如果覺得有用請點贊！！！
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