Designing a Spring Boot Starter for Lantu Pay’s Personal‑Sign‑Up SDK

Spring Boot Starter Design

The SDK is built by first creating a Starter module, defining public interfaces, and then implementing core business classes. A Properties class holds merchant ID, secret key and other configuration values. An auto‑configuration class injects these properties into LantuWxConfigStorage (stores parameters) and LantuWxPayService (global entry point for business code). The repository URL is https://github.com/wuchubuzai2018/lantu-pay-sdk.

HTTP Framework Layer Design

The SDK abstracts HTTP requests using a combination of the Strategy pattern and the Template Method pattern. Three interfaces— RequestHttp, RequestExecutor, ResponseHandler —and two abstract classes define a generic request flow that can be implemented with different HTTP clients such as OkHttp, HttpClient or RestTemplate.

RequestExecutor

represents the executor (GET, POST, etc.). ResponseHandler parses the raw response. An AbstractPostRequestExecutor routes POST requests to a concrete OkHttpSimplePostRequestExecutor, encapsulating the core OkHttp logic.

Request and Response Model Design

Request and response POJOs follow the Open API specification. A common abstract class AbstractWxPayRequest provides fields such as merchant ID, timestamp and signature, annotated with FastJSON @JSONField to map JSON names. It implements checkFields for required‑parameter validation and checkAndSign for unified signing.

Each API (order creation, query, refund) has a concrete request class extending this base. A generic response wrapper uses generics to deserialize different payloads.