Retrofit： 自定义注解

场景：在网络请求中，有些接口需要添加token认证，有些接口不需要

1. 自定义注解类

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface Token {
    boolean value() default true;
}

2. 在Interceptor拦截器中实现

Java:

@Override
public Response intercept(Chain chain) throws IOException {
    Request original = chain.request();
    // 重新进行build
    Request.Builder builder = original.newBuilder();
    final Token annotation = Objects.requireNonNull(original.tag(Invocation.class)).method().getAnnotation(Token.class);
    String accessToken = CacheUtil.getAccessToken();
    //Token注解为空，或者value 是 true的时候注入Token
    if (annotation == null || annotation.value()) {
        //全局添加请求头token
        if (!TextUtils.isEmpty(accessToken)) {
            // 注入一个token
            builder.addHeader(ACCESS_TOKEN_NAME, "bearer  " + accessToken);
        }
    }
    builder.addHeader(AUTHORIZATION,AUTHORIZATION_VALUE);
    return response;
}

Kotlin:

override fun intercept(chain: Interceptor.Chain): Response {
        val original = chain.request()
        //重新 build
        val builder = original.newBuilder()
        //获取Response
        val response = chain.proceed(builder.build())
        //添加公共头
        builder.addHeader(AUTHORIZATION, AUTHORIZATION_VALUE)
        //拿到注解类Token.kt
        val annotation =
            original.tag(Invocation::class.java)?.method()?.getAnnotation(Token::class.java)
        //没有注解，或者注解的属性 value 是 true的时候注入token
        annotation?.value.run {
            accessToken?.let {
                builder.addHeader(ACCESS_TOKEN_NAME,"bearer  $it")
            }
        }
        return response
    }

3.使用：在 Service接口的方法上，添加注解

@Token(value = false) //或者 @Token 或者 @Token(value = true)
suspend fun login(
       @Field("username") username: String,
       @Field("password") password: String
): LoginClient