将 JSON Object 从 Postman 发送到 Restful webservices

Question

为了练习，我试图在 postman 上进行 POST 调用，具有以下类，但它总是给我一个错误，它无法读取数据。

GET 将数据库中的各种用户和评论的 POST 交还给我，其中我 go 手动创建新用户（即通过设置字符串“blabla”）有效。 我希望我的 POST 从 postman 主体中获取 json object

 { "username": "1", "password": "2", "email": "3" }

并发送请求我在数据库中输入新用户。 我能怎么做？

用户DB.java

 public class UserDB { public void insertUser(User user) { EntityManager entityManager = JPAUtil.getEntityManagerFactory().createEntityManager(); EntityTransaction entityTransaction = entityManager.getTransaction(); entityTransaction.begin(); user.setUsername(user.getUsername()); user.setPassword(user.getPassword()); user.setEmail(user.getEmail()); entityManager.persist(user); entityTransaction.commit(); }

用户.java

 @XmlRootElement(name = "user") @XmlAccessorType(XmlAccessType.FIELD) @Entity @Table(name = "users") public class User { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) @Column(name = "user_id") private int user_id; @Column(name = "username") private String username; @Column(name = "password") private String password; @Column(name = "email") private String email; public User() { } public User(int user_id, String username, String password, String email) { this.user_id = user_id; this.username = username; this.password = password; this.email = email; } public User(String username, String password, String email) { this.username = username; this.password = password; this.email = email; } public int getUser_id() { return user_id; } public void setUser_id(int user_id) { this.user_id = user_id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String passoword) { this.password = passoword; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } }

RestUser.java

 @Path("/users") public class RestUser { private UserDB userDB; public RestUser() { this.userDB = new UserDB(); } @GET @Produces(MediaType.APPLICATION_JSON) public String getUsers_JSON() { String listUser = null; List<User> list = userDB.selectAllUsers(); Gson gson = new Gson(); listUser = gson.toJson(list); return listUser; } @GET @Path("/{id}") @Produces(MediaType.APPLICATION_JSON) public String getUser_byid(@PathParam("id") int id) { String u = null; User user = userDB.selectUser_ID(id); Gson gson = new Gson(); u = gson.toJson(user); return u; } /* @POST @Produces(MediaType.APPLICATION_JSON) public String message() { String u = null; Gson gson = new Gson(); User user = new User("user", "sss", "sss"); u = gson.toJson(user); userDB.insertUser(user); return u; } */ @POST @Path("/insert") @Produces(MediaType.APPLICATION_JSON) public void createUser(@QueryParam("username") String username,@QueryParam("password") String password,@QueryParam("email") String email) { User newuser = new User(username, password, email); userDB.insertUser(newuser); } }

我添加了我的 pom.xml

 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.exercises</groupId> <artifactId>UserManagement</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>war</packaging> <properties> <maven.compiler.target>17</maven.compiler.target> <maven.compiler.source>17</maven.compiler.source> </properties> <dependencies> <:-- https.//mvnrepository.com/artifact/com.googlecode.json-simple/json-simple --> <dependency> <groupId>com.googlecode.json-simple</groupId> <artifactId>json-simple</artifactId> <version>1.1.1</version> </dependency> <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.8.9</version> </dependency> <dependency> <groupId>org.glassfish.jersey.media</groupId> <artifactId>jersey-media-json-jackson</artifactId> <version>2.0</version> </dependency> <dependency> <groupId>org.glassfish.jersey.containers</groupId> <artifactId>jersey-container-servlet-core</artifactId> <version>2.0</version> </dependency> <dependency> <groupId>org.glassfish.jersey.core</groupId> <artifactId>jersey-client</artifactId> <version>2.0</version> </dependency> <dependency> <groupId>org.glassfish.jersey.core</groupId> <artifactId>jersey-server</artifactId> <version>2.0</version> </dependency> <dependency> <groupId>javax.xml.bind</groupId> <artifactId>jaxb-api</artifactId> <version>2.3.1</version> </dependency> <dependency> <groupId>org.eclipse.persistence</groupId> <artifactId>javax.persistence</artifactId> <version>2.2.1</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-core</artifactId> <version>5.6.9.Final</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-entitymanager</artifactId> <version>5.6.9.Final</version> </dependency> <dependency> <groupId>javax.servlet</groupId> <artifactId>javax.servlet-api</artifactId> <version>4.0.1</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax.servlet.jsp</groupId> <artifactId>javax.servlet.jsp-api</artifactId> <version>2.3.3</version> <scope>provided</scope> </dependency> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> <scope>provided</scope> </dependency> <dependency> <groupId>org.glassfish.web</groupId> <artifactId>javax.servlet.jsp.jstl</artifactId> <version>1.2.5</version> <exclusions> <exclusion> <groupId>javax.servlet</groupId> <artifactId>servlet-api</artifactId> </exclusion> <exclusion> <groupId>javax.servlet.jsp</groupId> <artifactId>jsp-api</artifactId> </exclusion> </exclusions> </dependency> </dependencies> <build> <finalName>UserManagement</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-war-plugin</artifactId> <version>3.3 2</version> </plugin> </plugins> </build> </project>

和我的 web.xml

 <?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"> <servlet> <servlet-name>jerseyServlet</servlet-name> <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class> <init-param> <param-name>jersey.config.server.provider.packages</param-name> <param-value>net.java.webservice</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>jerseyServlet</servlet-name> <url-pattern>/rest/*</url-pattern> </servlet-mapping> </web-app>

Answer 1

在您的 controller 方法createUser ，您为用户属性定义了三个查询参数，而不是使用请求正文来接收用户数据。 如果您想在请求正文中接收用户 object 作为 JSON 试试这个：

 @POST @Path("/insert") @Consumes(MediaType.APPLICATION_JSON) @Produces(MediaType.APPLICATION_JSON) public void createUser(User user) { userDB.insertUser(user); }

注意@Consumes注释。 When a HTTP POST request is sent to /users/insert (you could also leave /insert out, see below) the createUser method will be called and the JSON document with the user details will be converted into a Java object of the type User.

您可以将其简化为：

 @POST @Consumes(MediaType.APPLICATION_JSON) @Produces(MediaType.APPLICATION_JSON) public void createUser(User user) { userDB.insertUser(user); }