如何使用Java从同一服务发送多个HTTP请求？

Question

Java noob在这里。我正在尝试按照下图开发Web服务。

1. 将POST请求发送到REST服务器时，它们具有某些值，这些值（正在循环中从列表中读取）将插入到表（具有ID的新行）中。服务器返回HTTP 202 Accepted。

2. 为确保创建ID为1的资源，发出GET请求，将POJO返回为Json。

3. 最后，发送PATCH请求以更新特定列。

我编写了一个服务类，当分别调用每个API时，它会执行所有三个任务。我需要实现一些将POST请求发送到服务器时自动执行步骤2和3的功能。到目前为止，这是我的代码。

@Path("attachments")
public class FilesService {
private TiedostoService tiedostoService;
private AttachmentService attachmentService;    

@GET
@Path("{id}")
@Produces({MediaType.APPLICATION_JSON})
public Response listAttachmentsAsJson(@PathParam("id") Integer attachmentId) throws Exception {
    attachmentService = new AttachmentService();
    Gson gson = new GsonBuilder().excludeFieldsWithoutExposeAnnotation().create();
    Attachment attachment = attachmentService.getAttachment(attachmentId);
    String jsonString = gson.toJson(attachment.toString());
    return Response.status(Response.Status.OK).entity(jsonString).build();
}

@PATCH
@Path("{id}")
@Produces({MediaType.APPLICATION_JSON})
public Response patchAttachments(@PathParam("id") Integer attachmentId) throws Exception {
    attachmentService = new AttachmentService();
    Integer update = attachmentService.update(attachmentId);
    String jsonString = new Gson().toJson(update);
    return Response.status(Response.Status.ACCEPTED).entity(jsonString).build();
}

@POST
@Produces({MediaType.APPLICATION_JSON})
public Response migrateToMinio(@Context UriInfo uriInfo) throws Exception {
    Response response;
    List<String> responseList = new ArrayList<>();
    tiedostoService = new TiedostoService();
    attachmentService = new AttachmentService();
    List<Tiedosto> tiedostoList = tiedostoService.getAllFiles();
    String responseString = null;
    int i = 1;
    for (Tiedosto tiedosto : tiedostoList) {
        Attachment attachment = new Attachment();
        attachment.setCustomerId(tiedosto.getCustomerId());
        attachment.setSize(tiedosto.getFileSize());
        Integer id = attachmentService.createNew(attachment);
        if (id == 1) {
            UriBuilder builder = uriInfo.getAbsolutePathBuilder();
            builder.path(Integer.toString(i));
            response = Response.created(builder.build()).build();
            System.out.println(response);
            responseString = response.toString();
        }
        responseList.add(responseString);
        i++;
    }
    String jsonString = new Gson().toJson(responseList);
    return Response.status(Response.Status.OK).entity(jsonString).build();
}

}

当我使用curl或postman测试各个端点时，它们按预期方式工作，但我在如何在POST之后自动执行GET和PATCH方面陷入了困境。我真的很感谢一些建议/建议/帮助。