java - 错误 400 错误请求

Question

我在提出好的请求时遇到一些问题。

@Path("/activitiesGenerator")
public class ActivityResource {

ActivityStub acstub = new ActivityStub();

@GET
@Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
public Collection<Activity> getAllActivities(){

    return acstub.Find_All_Activities();
}


@GET
@Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
@Path("{activityId}") // Will act as parameter that will take value from the browser!
public Response getActivity(@PathParam("activityId") String activityId){

    if(activityId.equals(null) || activityId.length() < 4){

        return Response.status(Status.BAD_REQUEST).build();
    }

    Activity activity  = acstub.FindActivity(activityId);

    if(activity.equals(null)){

        return Response.status(Status.NOT_FOUND).build();
    }

    return Response.ok().entity(activity).build();
}

从这里我传递值!

@Test
public void main() {

    ActivityClient client = new ActivityClient();

    Activity activity = client.get("3204987");

    System.out.println(activity);

    assertNotNull(activity);
}

这里我检查响应..

public Activity get(String id){

    WebTarget target = client.target("http://localhost:8080/Activities/rest/");
    Response response = target.path("activitiesGenerator/"+id).request(MediaType.APPLICATION_JSON).get(Response.class);

    System.out.println(response.getStatus());

    if(response.getStatus() != 200){

        throw new RuntimeException(response.getStatus()+ ": there was an error on the server");
    }

    return response.readEntity(Activity.class);

}

我从 get 方法中得到一个异常。响应是 400 错误请求。 我做错了什么？

这是我的 web.xml 文件!

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
    id="WebApp_ID" version="3.1">

    <display-name>Activities</display-name>
    <servlet>
        <servlet-name>ActiviteExample</servlet-name>
        <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
        <init-param>
            <param-name>jersey.config.server.provider.packages</param-name>
            <param-value>activity.model</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>ActiviteExample</servlet-name>
        <url-pattern>/rest/*</url-pattern>
    </servlet-mapping>
</web-app>

 Could not get any response
 This seems to be like an error connecting to      http://HTTP://localhost:8080/Activities/rest/activities-generator/3204987.
 Why this might have happened:
 The server couldn't send a response:
 Ensure that the backend is working properly
 SSL connections are being blocked:
 Fix this by importing SSL certificates in Chrome
 Cookies not being sent:

这是我从 postman 那里得到的信息。如果有人能更具体地向我解释这个可能的解决方案，我将不胜感激......

Answer 1

将 Accepts header 添加到客户端代码中。 Accepts header 将告诉服务器发出请求的客户端愿意采用特定的 Mime 类型。如果您需要 json，请指定 application/json。

request(MediaType.APPLICATION_JSON)只会告诉发送到服务器的数据是json。它并没有告诉你你愿意接受什么。

在浏览器中发出请求并使用一些浏览器插件来设置 header 并观察响应。

了解有关 Accept header here 的更多信息