Retrofit
[toc]
Retrofit 使用
Retrofit retrofit = new Retrofit.Builder()
.baseUrl("https://api.example.com/")
.addConverterFactory(GsonConverterFactory.create())
.build();
MyApi api = retrofit.create(MyApi.class);
Response<User> user = api.getUser().execute();
Retrifit.Builder
public static final class Builder {
//....
/**
Correct: Base URL: http://example.com/api/ Endpoint: foo/bar/ Result: http://example.com/api/foo/bar/
Incorrect: Base URL: http://example.com/api Endpoint: foo/bar/ Result: http://example.com/foo/bar/
This method enforces that baseUrl has a trailing /.
Endpoint values which contain a leading / are absolute.
Absolute values retain only the host from baseUrl and ignore any specified path components.
Base URL: http://example.com/api/ Endpoint: /foo/bar/ Result: http://example.com/foo/bar/
Base URL: http://example.com/ Endpoint: /foo/bar/ Result: http://example.com/foo/bar/
Endpoint values may be a full URL.
Values which have a host replace the host of baseUrl and values also with a scheme replace the scheme of baseUrl.
Base URL: http://example.com/ Endpoint: https://github.com/square/retrofit/ Result: https://github.com/square/retrofit/
Base URL: http://example.com Endpoint: //github.com/square/retrofit/ Result: http://github.com/square/retrofit/ (note the scheme stays 'http')
*/
public Builder baseUrl(HttpUrl baseUrl) {
checkNotNull(baseUrl, "baseUrl == null");
List<String> pathSegments = baseUrl.pathSegments();
if (!"".equals(pathSegments.get(pathSegments.size() - 1))) {
throw new IllegalArgumentException("baseUrl must end in /: " + baseUrl);
}
this.baseUrl = baseUrl;
return this;
}
public Retrofit build() {
//必须有baseUrl
if (baseUrl == null) {
throw new IllegalStateException("Base URL required.");
}
okhttp3.Call.Factory callFactory = this.callFactory;
if (callFactory == null) {
callFactory = new OkHttpClient();
}
Executor callbackExecutor = this.callbackExecutor;
if (callbackExecutor == null) {
callbackExecutor = platform.defaultCallbackExecutor();
}
// Make a defensive copy of the adapters and add the default Call adapter.
//添加完我们设置的CallAdapter.Factory之后将DefaultCallAdapterFactory添加到最后
List<CallAdapter.Factory> callAdapterFactories = new ArrayList<>(this.callAdapterFactories);
callAdapterFactories.addAll(platform.defaultCallAdapterFactories(callbackExecutor));
// Make a defensive copy of the converters.
//先添加内置的BuiltInConverters在添加我们添加的
List<Converter.Factory> converterFactories = new ArrayList<>(
1 + this.converterFactories.size() + platform.defaultConverterFactoriesSize());
// Add the built-in converter factory first. This prevents overriding its behavior but also
// ensures correct behavior when using converters that consume all types.
converterFactories.add(new BuiltInConverters());
converterFactories.addAll(this.converterFactories);
converterFactories.addAll(platform.defaultConverterFactories());
return new Retrofit(callFactory, baseUrl, unmodifiableList(converterFactories),
unmodifiableList(callAdapterFactories), callbackExecutor, validateEagerly);
}
}
create方法
public <T> T create(final Class<T> service) {
//检查service 必须是个接口 必须没有继承其他接口
Utils.validateServiceInterface(service);
//验证所有方法
if (validateEagerly) {
eagerlyValidateMethods(service);
}
//动态代理
return (T) Proxy.newProxyInstance(service.getClassLoader(), new Class<?>[] { service },
new InvocationHandler() {
private final Platform platform = Platform.get();
private final Object[] emptyArgs = new Object[0];
@Override public @Nullable Object invoke(Object proxy, Method method,
@Nullable Object[] args) throws Throwable {
// If the method is a method from Object then defer to normal invocation.
//object的方法正常调用
if (method.getDeclaringClass() == Object.class) {
return method.invoke(this, args);
}
if (platform.isDefaultMethod(method)) {
return platform.invokeDefaultMethod(method, service, proxy, args);
}
//获取ServiceMethod并执行
return loadServiceMethod(method).invoke(args != null ? args : emptyArgs);
}
});
}
ServiceMethod<?> loadServiceMethod(Method method) {
//先从缓存中获取如果获取到直接返回
ServiceMethod<?> result = serviceMethodCache.get(method);
if (result != null) return result;
//如果没有则先锁
synchronized (serviceMethodCache) {
//从新获取,如果还没有就解析生成一个并缓存
result = serviceMethodCache.get(method);
if (result == null) {
result = ServiceMethod.parseAnnotations(this, method);
serviceMethodCache.put(method, result);
}
}
return result;
}
ServiceMethod
abstract class ServiceMethod<T> {
static <T> ServiceMethod<T> parseAnnotations(Retrofit retrofit, Method method) {
//在RequestFacory的Bbuilder中解析注解
RequestFactory requestFactory = RequestFactory.parseAnnotations(retrofit, method);
Type returnType = method.getGenericReturnType();
//返回值类型不能包含通配符和变量 也不能返回void
if (Utils.hasUnresolvableType(returnType)) {
throw methodError(method,
"Method return type must not include a type variable or wildcard: %s", returnType);
}
if (returnType == void.class) {
throw methodError(method, "Service methods cannot return void.");
}
//解析选择 callAdapter:可以处理返回值类型 和 responseConverter: 将ResponseBody转换为泛型参数
//返回是内置的HttpServiceMethod的子类实例
return HttpServiceMethod.parseAnnotations(retrofit, method, requestFactory);
}
//最后调用的是这方法
abstract @Nullable T invoke(Object[] args);
}
HttpServiceMethod内置的子类
static final class CallAdapted<ResponseT, ReturnT> extends HttpServiceMethod<ResponseT, ReturnT> {
private final CallAdapter<ResponseT, ReturnT> callAdapter;
CallAdapted(RequestFactory requestFactory, okhttp3.Call.Factory callFactory,
Converter<ResponseBody, ResponseT> responseConverter,
CallAdapter<ResponseT, ReturnT> callAdapter) {
super(requestFactory, callFactory, responseConverter);
this.callAdapter = callAdapter;
}
@Override protected ReturnT adapt(Call<ResponseT> call, Object[] args) {
//调用了callAdapter。adapt
return callAdapter.adapt(call);
}
}
HttpServiceMethod invoke方法
@Override final @Nullable ReturnT invoke(Object[] args) {
Call<ResponseT> call = new OkHttpCall<>(requestFactory, args, callFactory, responseConverter);
//调用了adapt,直接返回结果 实际是子类实现了
return adapt(call, args);
}
protected abstract @Nullable ReturnT adapt(Call<ResponseT> call, Object[] args);
CallAdapter
public interface CallAdapter<R, T> {
//泛型中的参数类型
Type responseType();
//将 call<R> R是可以处理的类型比如ResponseBody 转换为 返回值类型,比如 Call<ResponseBody>
T adapt(Call<R> call);
}
我们看下默认的CallAdapter
DefaultCallAdapterFactory
final class DefaultCallAdapterFactory extends CallAdapter.Factory {
private final @Nullable Executor callbackExecutor;
DefaultCallAdapterFactory(@Nullable Executor callbackExecutor) {
this.callbackExecutor = callbackExecutor;
}
@Override public @Nullable CallAdapter<?, ?> get(
Type returnType, Annotation[] annotations, Retrofit retrofit) {
//如果返回类型是不是Call 返回null表示处理不了
if (getRawType(returnType) != Call.class) {
return null;
}
//如果不是参数化类型 就是带泛型的也不行
if (!(returnType instanceof ParameterizedType)) {
throw new IllegalArgumentException(
"Call return type must be parameterized as Call<Foo> or Call<? extends Foo>");
}
//返回泛型中的类型
final Type responseType = Utils.getParameterUpperBound(0, (ParameterizedType) returnType);
final Executor executor = Utils.isAnnotationPresent(annotations, SkipCallbackExecutor.class)
? null
: callbackExecutor;
return new CallAdapter<Object, Call<?>>() {
@Override public Type responseType() {
return responseType;
}
@Override public Call<Object> adapt(Call<Object> call) {
//直接返回call
return executor == null
? call
: new ExecutorCallbackCall<>(executor, call);
}
};
}
}
流程到此结束
我们在crete的时候返回一个动态代理的类
在调用接口中的方法时候会把已经解析的方法处理类ServiceMethod 实际是子类HttpServiceMethod的内置实现类 持有了RequestFactory callFactory responseConverter callAdapter
在查找需要的calladapter 和 Converter 的时候
/**
* Returns the {@link CallAdapter} for {@code returnType} from the available {@linkplain
* #callAdapterFactories() factories} except {@code skipPast}.
*
* @throws IllegalArgumentException if no call adapter available for {@code type}.
*/
public CallAdapter<?, ?> nextCallAdapter(@Nullable CallAdapter.Factory skipPast, Type returnType,
Annotation[] annotations) {
checkNotNull(returnType, "returnType == null");
checkNotNull(annotations, "annotations == null");
int start = callAdapterFactories.indexOf(skipPast) + 1;
for (int i = start, count = callAdapterFactories.size(); i < count; i++) {
//工厂返回的get 如果返回不是null则表示可以处理,直接返回,所以添加顺序很关键
CallAdapter<?, ?> adapter = callAdapterFactories.get(i).get(returnType, annotations, this);
if (adapter != null) {
return adapter;
}
}
//没有找到抛异常
StringBuilder builder = new StringBuilder("Could not locate call adapter for ")
.append(returnType)
.append(".\n");
if (skipPast != null) {
builder.append(" Skipped:");
for (int i = 0; i < start; i++) {
builder.append("\n * ").append(callAdapterFactories.get(i).getClass().getName());
}
builder.append('\n');
}
builder.append(" Tried:");
for (int i = start, count = callAdapterFactories.size(); i < count; i++) {
builder.append("\n * ").append(callAdapterFactories.get(i).getClass().getName());
}
throw new IllegalArgumentException(builder.toString());
}
public <T> Converter<T, RequestBody> nextRequestBodyConverter(
@Nullable Converter.Factory skipPast, Type type, Annotation[] parameterAnnotations,
Annotation[] methodAnnotations) {
checkNotNull(type, "type == null");
checkNotNull(parameterAnnotations, "parameterAnnotations == null");
checkNotNull(methodAnnotations, "methodAnnotations == null");
int start = converterFactories.indexOf(skipPast) + 1;
for (int i = start, count = converterFactories.size(); i < count; i++) {
Converter.Factory factory = converterFactories.get(i);
//如果能将T转换成RequestBody不返回nul表示可以处理,直接返回
Converter<?, RequestBody> converter =
factory.requestBodyConverter(type, parameterAnnotations, methodAnnotations, this);
if (converter != null) {
//noinspection unchecked
return (Converter<T, RequestBody>) converter;
}
}
StringBuilder builder = new StringBuilder("Could not locate RequestBody converter for ")
.append(type)
.append(".\n");
if (skipPast != null) {
builder.append(" Skipped:");
for (int i = 0; i < start; i++) {
builder.append("\n * ").append(converterFactories.get(i).getClass().getName());
}
builder.append('\n');
}
builder.append(" Tried:");
for (int i = start, count = converterFactories.size(); i < count; i++) {
builder.append("\n * ").append(converterFactories.get(i).getClass().getName());
}
throw new IllegalArgumentException(builder.toString());
}
public <T> Converter<ResponseBody, T> nextResponseBodyConverter(
@Nullable Converter.Factory skipPast, Type type, Annotation[] annotations) {
checkNotNull(type, "type == null");
checkNotNull(annotations, "annotations == null");
int start = converterFactories.indexOf(skipPast) + 1;
for (int i = start, count = converterFactories.size(); i < count; i++) {
//可以将ResponseBody转换成需要的类型不可以就返回null 继续下一个,可以就直接返回了
Converter<ResponseBody, ?> converter =
converterFactories.get(i).responseBodyConverter(type, annotations, this);
if (converter != null) {
//noinspection unchecked
return (Converter<ResponseBody, T>) converter;
}
}
StringBuilder builder = new StringBuilder("Could not locate ResponseBody converter for ")
.append(type)
.append(".\n");
if (skipPast != null) {
builder.append(" Skipped:");
for (int i = 0; i < start; i++) {
builder.append("\n * ").append(converterFactories.get(i).getClass().getName());
}
builder.append('\n');
}
builder.append(" Tried:");
for (int i = start, count = converterFactories.size(); i < count; i++) {
builder.append("\n * ").append(converterFactories.get(i).getClass().getName());
}
throw new IllegalArgumentException(builder.toString());
}
可以看到都是找打第一个可以处理的就直接返回了,所以添加的顺序很重要
解析方法上的注解主要是RequestFactory
RequestFactory build() {
//挨个解析方法上的注解
for (Annotation annotation : methodAnnotations) {
parseMethodAnnotation(annotation);
}
//必须指定httpMethod
if (httpMethod == null) {
throw methodError(method, "HTTP method annotation is required (e.g., @GET, @POST, etc.).");
}
//如果没有requestbody 就不能是Multipart和FormUrlEncoded
if (!hasBody) {
if (isMultipart) {
throw methodError(method,
"Multipart can only be specified on HTTP methods with request body (e.g., @POST).");
}
if (isFormEncoded) {
throw methodError(method, "FormUrlEncoded can only be specified on HTTP methods with "
+ "request body (e.g., @POST).");
}
}
//解析参数上的注解
int parameterCount = parameterAnnotationsArray.length;
parameterHandlers = new ParameterHandler<?>[parameterCount];
for (int p = 0, lastParameter = parameterCount - 1; p < parameterCount; p++) {
parameterHandlers[p] =
parseParameter(p, parameterTypes[p], parameterAnnotationsArray[p], p == lastParameter);
}
//相对没有拿到url
if (relativeUrl == null && !gotUrl) {
throw methodError(method, "Missing either @%s URL or @Url parameter.", httpMethod);
}
if (!isFormEncoded && !isMultipart && !hasBody && gotBody) {
throw methodError(method, "Non-body HTTP method cannot contain @Body.");
}
//表单的类型最好要加一个
if (isFormEncoded && !gotField) {
throw methodError(method, "Form-encoded method must contain at least one @Field.");
}
//Multipart最少要有一个
if (isMultipart && !gotPart) {
throw methodError(method, "Multipart method must contain at least one @Part.");
}
return new RequestFactory(this);
}
解析方法上的注解
private void parseMethodAnnotation(Annotation annotation) {
if (annotation instanceof DELETE) {
parseHttpMethodAndPath("DELETE", ((DELETE) annotation).value(), false);
} else if (annotation instanceof GET) {
//如果是get注解 get 方法解析 get方法不带requestbody
parseHttpMethodAndPath("GET", ((GET) annotation).value(), false);
} else if (annotation instanceof HEAD) {
parseHttpMethodAndPath("HEAD", ((HEAD) annotation).value(), false);
} else if (annotation instanceof PATCH) {
parseHttpMethodAndPath("PATCH", ((PATCH) annotation).value(), true);
} else if (annotation instanceof POST) {
parseHttpMethodAndPath("POST", ((POST) annotation).value(), true);
//如果是post注解 post 方法解析 post方法有requestbody
} else if (annotation instanceof PUT) {
parseHttpMethodAndPath("PUT", ((PUT) annotation).value(), true);
} else if (annotation instanceof OPTIONS) {
parseHttpMethodAndPath("OPTIONS", ((OPTIONS) annotation).value(), false);
} else if (annotation instanceof HTTP) {
HTTP http = (HTTP) annotation;
parseHttpMethodAndPath(http.method(), http.path(), http.hasBody());
} else if (annotation instanceof retrofit2.http.Headers) {
//解析heder
String[] headersToParse = ((retrofit2.http.Headers) annotation).value();
if (headersToParse.length == 0) {
throw methodError(method, "@Headers annotation is empty.");
}
headers = parseHeaders(headersToParse);
} else if (annotation instanceof Multipart) {
//FormEncoded Multipart 不能同时存在
if (isFormEncoded) {
throw methodError(method, "Only one encoding annotation is allowed.");
}
isMultipart = true;
} else if (annotation instanceof FormUrlEncoded) {
if (isMultipart) {
throw methodError(method, "Only one encoding annotation is allowed.");
}
isFormEncoded = true;
}
}
private void parseHttpMethodAndPath(String httpMethod, String value, boolean hasBody) {
if (this.httpMethod != null) {
throw methodError(method, "Only one HTTP method is allowed. Found: %s and %s.",
this.httpMethod, httpMethod);
}
this.httpMethod = httpMethod;
this.hasBody = hasBody;
if (value.isEmpty()) {
return;
}
//get方法 的url里面不要用拼接查询方式
// Get the relative URL path and existing query string, if present.
int question = value.indexOf('?');
if (question != -1 && question < value.length() - 1) {
// Ensure the query string does not have any named parameters.
String queryParams = value.substring(question + 1);
Matcher queryParamMatcher = PARAM_URL_REGEX.matcher(queryParams);
if (queryParamMatcher.find()) {
throw methodError(method, "URL query string \"%s\" must not have replace block. "
+ "For dynamic query parameters use @Query.", queryParams);
}
}
this.relativeUrl = value;
this.relativeUrlParamNames = parsePathParameters(value);
}
//将url中的{}命中等待替换成实际值
static Set<String> parsePathParameters(String path) {
Matcher m = PARAM_URL_REGEX.matcher(path);
Set<String> patterns = new LinkedHashSet<>();
while (m.find()) {
patterns.add(m.group(1));
}
return patterns;
}
//解析方法注解的headers
private Headers parseHeaders(String[] headers) {
Headers.Builder builder = new Headers.Builder();
for (String header : headers) {
int colon = header.indexOf(':');
if (colon == -1 || colon == 0 || colon == header.length() - 1) {
throw methodError(method,
"@Headers value must be in the form \"Name: Value\". Found: \"%s\"", header);
}
String headerName = header.substring(0, colon);
String headerValue = header.substring(colon + 1).trim();
if ("Content-Type".equalsIgnoreCase(headerName)) {
try {
contentType = MediaType.get(headerValue);
} catch (IllegalArgumentException e) {
throw methodError(method, e, "Malformed content type: %s", headerValue);
}
} else {
builder.add(headerName, headerValue);
}
}
return builder.build();
}
解析参数上的注解
@Nullable
private ParameterHandler<?> parseParameterAnnotation(
int p, Type type, Annotation[] annotations, Annotation annotation) {
if (annotation instanceof Url) {
//不能有多个url url不i能在其他后面 url 和path 不能同时使用
validateResolvableType(p, type);
if (gotUrl) {
throw parameterError(method, p, "Multiple @Url method annotations found.");
}
if (gotPath) {
throw parameterError(method, p, "@Path parameters may not be used with @Url.");
}
if (gotQuery) {
throw parameterError(method, p, "A @Url parameter must not come after a @Query.");
}
if (gotQueryName) {
throw parameterError(method, p, "A @Url parameter must not come after a @QueryName.");
}
if (gotQueryMap) {
throw parameterError(method, p, "A @Url parameter must not come after a @QueryMap.");
}
if (relativeUrl != null) {
throw parameterError(method, p, "@Url cannot be used with @%s URL", httpMethod);
}
gotUrl = true;
if (type == HttpUrl.class
|| type == String.class
|| type == URI.class
|| (type instanceof Class && "android.net.Uri".equals(((Class<?>) type).getName()))) {
return new ParameterHandler.RelativeUrl(method, p);
} else {
throw parameterError(method, p,
"@Url must be okhttp3.HttpUrl, String, java.net.URI, or android.net.Uri type.");
}
} else if (annotation instanceof Path) {
//path不能再query 后面 不能和url同时使用 相对url不能为null
validateResolvableType(p, type);
if (gotQuery) {
throw parameterError(method, p, "A @Path parameter must not come after a @Query.");
}
if (gotQueryName) {
throw parameterError(method, p, "A @Path parameter must not come after a @QueryName.");
}
if (gotQueryMap) {
throw parameterError(method, p, "A @Path parameter must not come after a @QueryMap.");
}
if (gotUrl) {
throw parameterError(method, p, "@Path parameters may not be used with @Url.");
}
if (relativeUrl == null) {
throw parameterError(method, p, "@Path can only be used with relative url on @%s",
httpMethod);
}
gotPath = true;
Path path = (Path) annotation;
String name = path.value();
validatePathName(p, name);
Converter<?, String> converter = retrofit.stringConverter(type, annotations);
return new ParameterHandler.Path<>(method, p, name, converter, path.encoded());
} else if (annotation instanceof Query) {
//处理query注解
validateResolvableType(p, type);
Query query = (Query) annotation;
String name = query.value();
boolean encoded = query.encoded();
Class<?> rawParameterType = Utils.getRawType(type);
gotQuery = true;
//类型是否是集合 数组 等
if (Iterable.class.isAssignableFrom(rawParameterType)) {
if (!(type instanceof ParameterizedType)) {
throw parameterError(method, p, rawParameterType.getSimpleName()
+ " must include generic type (e.g., "
+ rawParameterType.getSimpleName()
+ "<String>)");
}
//如果是集合 获取泛型参数并拿到可以转换为string的转换器
ParameterizedType parameterizedType = (ParameterizedType) type;
Type iterableType = Utils.getParameterUpperBound(0, parameterizedType);
Converter<?, String> converter =
retrofit.stringConverter(iterableType, annotations);
return new ParameterHandler.Query<>(name, converter, encoded).iterable();
} else if (rawParameterType.isArray()) {
//数组
Class<?> arrayComponentType = boxIfPrimitive(rawParameterType.getComponentType());
Converter<?, String> converter =
retrofit.stringConverter(arrayComponentType, annotations);
return new ParameterHandler.Query<>(name, converter, encoded).array();
} else {
Converter<?, String> converter =
retrofit.stringConverter(type, annotations);
return new ParameterHandler.Query<>(name, converter, encoded);
}
} else if (annotation instanceof QueryName) {
//将queryname注解的拼接到相对url 只有name 没有value
validateResolvableType(p, type);
QueryName query = (QueryName) annotation;
boolean encoded = query.encoded();
Class<?> rawParameterType = Utils.getRawType(type);
gotQueryName = true;
if (Iterable.class.isAssignableFrom(rawParameterType)) {
if (!(type instanceof ParameterizedType)) {
throw parameterError(method, p, rawParameterType.getSimpleName()
+ " must include generic type (e.g., "
+ rawParameterType.getSimpleName()
+ "<String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) type;
Type iterableType = Utils.getParameterUpperBound(0, parameterizedType);
Converter<?, String> converter =
retrofit.stringConverter(iterableType, annotations);
return new ParameterHandler.QueryName<>(converter, encoded).iterable();
} else if (rawParameterType.isArray()) {
Class<?> arrayComponentType = boxIfPrimitive(rawParameterType.getComponentType());
Converter<?, String> converter =
retrofit.stringConverter(arrayComponentType, annotations);
return new ParameterHandler.QueryName<>(converter, encoded).array();
} else {
Converter<?, String> converter =
retrofit.stringConverter(type, annotations);
return new ParameterHandler.QueryName<>(converter, encoded);
}
} else if (annotation instanceof QueryMap) {
validateResolvableType(p, type);
Class<?> rawParameterType = Utils.getRawType(type);
gotQueryMap = true;
if (!Map.class.isAssignableFrom(rawParameterType)) {
throw parameterError(method, p, "@QueryMap parameter type must be Map.");
}
Type mapType = Utils.getSupertype(type, rawParameterType, Map.class);
if (!(mapType instanceof ParameterizedType)) {
throw parameterError(method, p,
"Map must include generic types (e.g., Map<String, String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) mapType;
Type keyType = Utils.getParameterUpperBound(0, parameterizedType);
if (String.class != keyType) {
throw parameterError(method, p, "@QueryMap keys must be of type String: " + keyType);
}
Type valueType = Utils.getParameterUpperBound(1, parameterizedType);
Converter<?, String> valueConverter =
retrofit.stringConverter(valueType, annotations);
return new ParameterHandler.QueryMap<>(method, p,
valueConverter, ((QueryMap) annotation).encoded());
} else if (annotation instanceof Header) {
validateResolvableType(p, type);
Header header = (Header) annotation;
String name = header.value();
Class<?> rawParameterType = Utils.getRawType(type);
if (Iterable.class.isAssignableFrom(rawParameterType)) {
if (!(type instanceof ParameterizedType)) {
throw parameterError(method, p, rawParameterType.getSimpleName()
+ " must include generic type (e.g., "
+ rawParameterType.getSimpleName()
+ "<String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) type;
Type iterableType = Utils.getParameterUpperBound(0, parameterizedType);
Converter<?, String> converter =
retrofit.stringConverter(iterableType, annotations);
return new ParameterHandler.Header<>(name, converter).iterable();
} else if (rawParameterType.isArray()) {
Class<?> arrayComponentType = boxIfPrimitive(rawParameterType.getComponentType());
Converter<?, String> converter =
retrofit.stringConverter(arrayComponentType, annotations);
return new ParameterHandler.Header<>(name, converter).array();
} else {
Converter<?, String> converter =
retrofit.stringConverter(type, annotations);
return new ParameterHandler.Header<>(name, converter);
}
} else if (annotation instanceof HeaderMap) {
validateResolvableType(p, type);
Class<?> rawParameterType = Utils.getRawType(type);
if (!Map.class.isAssignableFrom(rawParameterType)) {
throw parameterError(method, p, "@HeaderMap parameter type must be Map.");
}
Type mapType = Utils.getSupertype(type, rawParameterType, Map.class);
if (!(mapType instanceof ParameterizedType)) {
throw parameterError(method, p,
"Map must include generic types (e.g., Map<String, String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) mapType;
Type keyType = Utils.getParameterUpperBound(0, parameterizedType);
if (String.class != keyType) {
throw parameterError(method, p, "@HeaderMap keys must be of type String: " + keyType);
}
Type valueType = Utils.getParameterUpperBound(1, parameterizedType);
Converter<?, String> valueConverter =
retrofit.stringConverter(valueType, annotations);
return new ParameterHandler.HeaderMap<>(method, p, valueConverter);
} else if (annotation instanceof Field) {
validateResolvableType(p, type);
if (!isFormEncoded) {
throw parameterError(method, p, "@Field parameters can only be used with form encoding.");
}
Field field = (Field) annotation;
String name = field.value();
boolean encoded = field.encoded();
gotField = true;
Class<?> rawParameterType = Utils.getRawType(type);
if (Iterable.class.isAssignableFrom(rawParameterType)) {
if (!(type instanceof ParameterizedType)) {
throw parameterError(method, p, rawParameterType.getSimpleName()
+ " must include generic type (e.g., "
+ rawParameterType.getSimpleName()
+ "<String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) type;
Type iterableType = Utils.getParameterUpperBound(0, parameterizedType);
Converter<?, String> converter =
retrofit.stringConverter(iterableType, annotations);
return new ParameterHandler.Field<>(name, converter, encoded).iterable();
} else if (rawParameterType.isArray()) {
Class<?> arrayComponentType = boxIfPrimitive(rawParameterType.getComponentType());
Converter<?, String> converter =
retrofit.stringConverter(arrayComponentType, annotations);
return new ParameterHandler.Field<>(name, converter, encoded).array();
} else {
Converter<?, String> converter =
retrofit.stringConverter(type, annotations);
return new ParameterHandler.Field<>(name, converter, encoded);
}
} else if (annotation instanceof FieldMap) {
validateResolvableType(p, type);
if (!isFormEncoded) {
throw parameterError(method, p,
"@FieldMap parameters can only be used with form encoding.");
}
Class<?> rawParameterType = Utils.getRawType(type);
if (!Map.class.isAssignableFrom(rawParameterType)) {
throw parameterError(method, p, "@FieldMap parameter type must be Map.");
}
Type mapType = Utils.getSupertype(type, rawParameterType, Map.class);
if (!(mapType instanceof ParameterizedType)) {
throw parameterError(method, p,
"Map must include generic types (e.g., Map<String, String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) mapType;
Type keyType = Utils.getParameterUpperBound(0, parameterizedType);
if (String.class != keyType) {
throw parameterError(method, p, "@FieldMap keys must be of type String: " + keyType);
}
Type valueType = Utils.getParameterUpperBound(1, parameterizedType);
Converter<?, String> valueConverter =
retrofit.stringConverter(valueType, annotations);
gotField = true;
return new ParameterHandler.FieldMap<>(method, p,
valueConverter, ((FieldMap) annotation).encoded());
} else if (annotation instanceof Part) {
validateResolvableType(p, type);
if (!isMultipart) {
throw parameterError(method, p,
"@Part parameters can only be used with multipart encoding.");
}
Part part = (Part) annotation;
gotPart = true;
String partName = part.value();
Class<?> rawParameterType = Utils.getRawType(type);
if (partName.isEmpty()) {
if (Iterable.class.isAssignableFrom(rawParameterType)) {
if (!(type instanceof ParameterizedType)) {
throw parameterError(method, p, rawParameterType.getSimpleName()
+ " must include generic type (e.g., "
+ rawParameterType.getSimpleName()
+ "<String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) type;
Type iterableType = Utils.getParameterUpperBound(0, parameterizedType);
if (!MultipartBody.Part.class.isAssignableFrom(Utils.getRawType(iterableType))) {
throw parameterError(method, p,
"@Part annotation must supply a name or use MultipartBody.Part parameter type.");
}
return ParameterHandler.RawPart.INSTANCE.iterable();
} else if (rawParameterType.isArray()) {
Class<?> arrayComponentType = rawParameterType.getComponentType();
if (!MultipartBody.Part.class.isAssignableFrom(arrayComponentType)) {
throw parameterError(method, p,
"@Part annotation must supply a name or use MultipartBody.Part parameter type.");
}
return ParameterHandler.RawPart.INSTANCE.array();
} else if (MultipartBody.Part.class.isAssignableFrom(rawParameterType)) {
return ParameterHandler.RawPart.INSTANCE;
} else {
throw parameterError(method, p,
"@Part annotation must supply a name or use MultipartBody.Part parameter type.");
}
} else {
Headers headers =
Headers.of("Content-Disposition", "form-data; name=\"" + partName + "\"",
"Content-Transfer-Encoding", part.encoding());
if (Iterable.class.isAssignableFrom(rawParameterType)) {
if (!(type instanceof ParameterizedType)) {
throw parameterError(method, p, rawParameterType.getSimpleName()
+ " must include generic type (e.g., "
+ rawParameterType.getSimpleName()
+ "<String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) type;
Type iterableType = Utils.getParameterUpperBound(0, parameterizedType);
if (MultipartBody.Part.class.isAssignableFrom(Utils.getRawType(iterableType))) {
throw parameterError(method, p,
"@Part parameters using the MultipartBody.Part must not "
+ "include a part name in the annotation.");
}
Converter<?, RequestBody> converter =
retrofit.requestBodyConverter(iterableType, annotations, methodAnnotations);
return new ParameterHandler.Part<>(method, p, headers, converter).iterable();
} else if (rawParameterType.isArray()) {
Class<?> arrayComponentType = boxIfPrimitive(rawParameterType.getComponentType());
if (MultipartBody.Part.class.isAssignableFrom(arrayComponentType)) {
throw parameterError(method, p,
"@Part parameters using the MultipartBody.Part must not "
+ "include a part name in the annotation.");
}
Converter<?, RequestBody> converter =
retrofit.requestBodyConverter(arrayComponentType, annotations, methodAnnotations);
return new ParameterHandler.Part<>(method, p, headers, converter).array();
} else if (MultipartBody.Part.class.isAssignableFrom(rawParameterType)) {
throw parameterError(method, p,
"@Part parameters using the MultipartBody.Part must not "
+ "include a part name in the annotation.");
} else {
Converter<?, RequestBody> converter =
retrofit.requestBodyConverter(type, annotations, methodAnnotations);
return new ParameterHandler.Part<>(method, p, headers, converter);
}
}
} else if (annotation instanceof PartMap) {
validateResolvableType(p, type);
if (!isMultipart) {
throw parameterError(method, p,
"@PartMap parameters can only be used with multipart encoding.");
}
gotPart = true;
Class<?> rawParameterType = Utils.getRawType(type);
if (!Map.class.isAssignableFrom(rawParameterType)) {
throw parameterError(method, p, "@PartMap parameter type must be Map.");
}
Type mapType = Utils.getSupertype(type, rawParameterType, Map.class);
if (!(mapType instanceof ParameterizedType)) {
throw parameterError(method, p,
"Map must include generic types (e.g., Map<String, String>)");
}
ParameterizedType parameterizedType = (ParameterizedType) mapType;
Type keyType = Utils.getParameterUpperBound(0, parameterizedType);
if (String.class != keyType) {
throw parameterError(method, p, "@PartMap keys must be of type String: " + keyType);
}
Type valueType = Utils.getParameterUpperBound(1, parameterizedType);
if (MultipartBody.Part.class.isAssignableFrom(Utils.getRawType(valueType))) {
throw parameterError(method, p, "@PartMap values cannot be MultipartBody.Part. "
+ "Use @Part List<Part> or a different value type instead.");
}
Converter<?, RequestBody> valueConverter =
retrofit.requestBodyConverter(valueType, annotations, methodAnnotations);
PartMap partMap = (PartMap) annotation;
return new ParameterHandler.PartMap<>(method, p, valueConverter, partMap.encoding());
} else if (annotation instanceof Body) {
validateResolvableType(p, type);
if (isFormEncoded || isMultipart) {
throw parameterError(method, p,
"@Body parameters cannot be used with form or multi-part encoding.");
}
if (gotBody) {
throw parameterError(method, p, "Multiple @Body method annotations found.");
}
Converter<?, RequestBody> converter;
try {
converter = retrofit.requestBodyConverter(type, annotations, methodAnnotations);
} catch (RuntimeException e) {
// Wide exception range because factories are user code.
throw parameterError(method, e, p, "Unable to create @Body converter for %s", type);
}
gotBody = true;
return new ParameterHandler.Body<>(method, p, converter);
} else if (annotation instanceof Tag) {
validateResolvableType(p, type);
Class<?> tagType = Utils.getRawType(type);
for (int i = p - 1; i >= 0; i--) {
ParameterHandler<?> otherHandler = parameterHandlers[i];
if (otherHandler instanceof ParameterHandler.Tag
&& ((ParameterHandler.Tag) otherHandler).cls.equals(tagType)) {
throw parameterError(method, p, "@Tag type "
+ tagType.getName()
+ " is duplicate of parameter #"
+ (i + 1)
+ " and would always overwrite its value.");
}
}
return new ParameterHandler.Tag<>(tagType);
}
return null; // Not a Retrofit annotation.
}
abstract class ParameterHandler<T> {
abstract void apply(RequestBuilder builder, @Nullable T value) throws IOException;
}
每个参数的注解都会生成一个ParameterHandler的实例,在RequestFactory中的数组中parameterHandlers
在call的enqueue 和 execute 方法会调用createRawCall() 在这个方法中会调用 requestFactory.create(args) 会调用ParameterHandler的appliy组装Request,组装完request后会调用OK HTTP的方法去请求并等待返回结果,返回结果会用response转换器转换
okhttp3.Request create(Object[] args) throws IOException {
@SuppressWarnings("unchecked") // It is an error to invoke a method with the wrong arg types.
ParameterHandler<Object>[] handlers = (ParameterHandler<Object>[]) parameterHandlers;
int argumentCount = args.length;
if (argumentCount != handlers.length) {
throw new IllegalArgumentException("Argument count (" + argumentCount
+ ") doesn't match expected count (" + handlers.length + ")");
}
RequestBuilder requestBuilder = new RequestBuilder(httpMethod, baseUrl, relativeUrl,
headers, contentType, hasBody, isFormEncoded, isMultipart);
if (isKotlinSuspendFunction) {
// The Continuation is the last parameter and the handlers array contains null at that index.
argumentCount--;
}
List<Object> argumentList = new ArrayList<>(argumentCount);
for (int p = 0; p < argumentCount; p++) {
argumentList.add(args[p]);
handlers[p].apply(requestBuilder, args[p]);
}
return requestBuilder.get()
.tag(Invocation.class, new Invocation(method, argumentList))
.build();
}
网友评论