Java 无法将 JSON 对象发送到 Rest Web 服务

Unable to send JSON object to Rest web service

提问by MoShe

I have a REST web servce configure as the following:

我有一个 REST web 服务配置如下：

@Path("/users")
public class UserManager {

@Context
UriInfo uriInfo;

@POST
@Consumes("application/json")
public void createUser(User user) {
    URI uri = uriInfo.getAbsolutePathBuilder().path(user.getUserName())
            .build();
    Response res = Response.created(uri).build();
    try {
        MongoDbDataAccess.getInstance().addUser(user);
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

And My Tomcat server configure as the following:

我的Tomcat服务器配置如下：

<servlet>
  <servlet-name>Jersey REST Service</servlet-name>
  <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
  <init-param>
   <param-name>com.sun.jersey.config.property.packages</param-name>
   <param-value>anyq.server.anyq.manager</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
   <servlet-name>Jersey REST Service</servlet-name>
   <url-pattern>/rest/*</url-pattern>
</servlet-mapping>

The POJO I create look like the following:

我创建的 POJO 如下所示：

@XmlRootElement
public class User {

private long userId;
private String userName;
private String userPassword;

public User() {
    super();
}

public User(long userId, String userName, String userPassword) {
    super();
    this.userId = userId;
    this.userName = userName;
    this.userPassword = userPassword;
}

public long getUserId() {
    return userId;
}

public void setUserId(long userId) {
    this.userId = userId;
}

public String getUserName() {
    return userName;
}

public void setUserName(String userName) {
    this.userName = userName;
}

public String getUserPassword() {
    return userPassword;
}

public void setUserPassword(String userPassword) {
    this.userPassword = userPassword;
}

}

}

I create the a test client in order to test the createUser method:

我创建了一个测试客户端来测试 createUser 方法：

public class tester {

public static void main(String[] args) throws UnknownHostException {

    String USER_URI = "http://localhost:8080/AnyAppserver/rest/users";
    User user = new User((long) 451, "mosssi", "464asd64");

    Client client = Client.create();

    WebResource r = client.resource(USER_URI);

    ClientResponse response = r.accept(MediaType.APPLICATION_JSON).post(
            ClientResponse.class, user);


}

But I get the following error:

但我收到以下错误：

POST http://localhost:8080/AnyAppserver/rest/users returned a response status of 415 Unsupported Media Type

The wierd issue is when I change everything to appliction/xml it work perfectly

奇怪的问题是当我将所有内容更改为 appliction/xml 时，它运行良好

Any Idea why Json doesnt work for me?

知道为什么 Json 对我不起作用吗？

采纳答案by MGorgon

You are doing:

你在做：

User user = new User((long) 451, "mosssi", "464asd64");

ClientResponse response = r.accept(MediaType.APPLICATION_JSON).post(ClientResponse.class, user);

It's wrong. You should send to your service a real JSON String.

这是错的。您应该向您的服务发送一个真正的 JSON 字符串。

Get JSON parser, for example: gson, and do this:

获取 JSON 解析器，例如：gson，然后执行以下操作：

User user = new User(451, "mosssi", "464asd64");
String request = gson.toJson(user);
ClientResponse response = r.type(MediaType.APPLICATION_JSON).post(ClientResponse.class, request );

Don't use old Jersey-bundle library. Download 2.0 version: https://jersey.java.net/download.html

不要使用旧的 Jersey-bundle 库。下载2.0版本：https: //jersey.java.net/download.html

add all libs (lib and ext libraries) to your classpath.

将所有库（lib 和 ext 库）添加到您的类路径中。

Next, you need the Hymanson packages in your classpath: Hymanson-annotations-2.2.2.jar Hymanson-core-2.2.2.jar Hymanson-databind-2.2.2.jar Hymanson-jaxrs-base-2.2.1.jar Hymanson-jaxrs-json-provider-2.2.1.jar Hymanson-module-jaxb-annotations-2.2.2.jar

接下来，您需要类路径中的 Hymanson 包： Hymanson-annotations-2.2.2.jar Hymanson-core-2.2.2.jar Hymanson-databind-2.2.2.jar Hymanson-jaxrs-base-2.2.1.jar Hymanson -jaxrs-json-provider-2.2.1.jar Hymanson-module-jaxb-annotations-2.2.2.jar

Your service class should be similiar to this:

您的服务类应该类似于：

package anyq.server.anyq.manager;

import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.UriInfo;

import anyq.server.common.bean.User;

@Path("/users")
public class AnyQUserManager {

@Context
UriInfo uriInfo;

@POST
@Consumes(MediaType.APPLICATION_JSON)
public Response createUser(User user) {
    System.out.println("HELLO WORLD");
    return Response.status(666).entity("Hello world").build();
}
}

And, finaly, your web.xml should look like:

最后，您的 web.xml 应如下所示：

<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
version="2.4">

<servlet>
    <servlet-name>Jersey REST Service</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
    <init-param>
        <param-name>jersey.config.server.provider.packages</param-name>
        <param-value>anyq.server.anyq.manager, com.fasterxml.Hymanson.jaxrs.json</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>Jersey REST Service</servlet-name>
    <url-pattern>/rest/*</url-pattern>
</servlet-mapping>

In your client class, do this:

在您的客户端类中，执行以下操作：

    String USER_URI = "http://localhost:8080/AnyQserver/rest/users";
    User user = new anyq.server.common.bean.User();
    user.setUserId(15);
    user.setUserName("asd");
    user.setUserPassword("asd");

    Client client = Client.create();
    String request = new Gson().toJson(user);
    System.out.println(request);
    WebResource r = client.resource(USER_URI);
    ClientResponse response = r.type(MediaType.APPLICATION_JSON).post(
            ClientResponse.class, request);
    System.out.println(response.getStatus());

Restart server and run client. If everything went fine, server should print:

重新启动服务器并运行客户端。如果一切顺利，服务器应该打印：

INFO: Server startup in 2256 ms
HELLO WORLD

and client:

和客户：

{"userId":15,"userName":"asd","userPassword":"asd"}
666

Good luck!

祝你好运！

Also, I really sugest you to migrate to maven.

另外，我真的建议您迁移到 maven。