java - 线程中的异常 "main"org.hibernate.InvalidMappingException : Could not parse mapping document from resource userdata. hbm.xml

Question

这是我的目录结构:

以下是错误:

我正在尝试我的第一个 hibernate 程序，但收到此错误。我的程序只是在数据库中输入用户名、密码和电子邮件。我创建了一个 POJO user.java、一个 UserManager.java 和两个 xml 文件，一个用于配置，另一个用于 hibernate 映射。这个错误我已经尝试了好久了，还是没有解决。

这是我的用户.java:

    package com.csc.training.Twitter;

    public class User {

        String username;
        String password;
        String email;
        int user_id;
        Date joined;

public Date getJoined() {
        return joined;
    }
    public void setJoined(Date joined) {
        this.joined = joined;
    }

        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 password) {
            this.password = password;
        }
        public String getEmail() {
            return email;
        }
        public void setEmail(String email) {
            this.email = email;
        }   
    }

UserManager.java

package com.csc.training.Twitter;

import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.classic.Session;

public class UserManager {

    public void registration() {

    Configuration config=new Configuration();
    config.configure("hibernate.cfg.xml");
    SessionFactory factory=config.buildSessionFactory();

    Session session=factory.openSession();

    Transaction transaction = (Transaction) session.beginTransaction();

    User user = new User(); 

    user.setUsername("fname2");
    user.setPassword("lname2");
    user.setEmail("def@def.def");

    session.persist(user);

    transaction.commit();

    System.out.println("User Id : " + user.getUser_id());

    session.close();
    System.out.println("Employee update successful...");

}

public static void main(String[] args) {
    UserManager um=new UserManager();
    um.registration();
}
}

这些是 xml 文件..

用户数据.hbm.xml:

    <?xml version="1.0" encoding="utf-8"?>
    <!DOCTYPE hibernate-mapping PUBLIC 
 "-//Hibernate/Hibernate Mapping DTD//EN"
 "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

    <hibernate-mapping>
       <class name="com.csc.training.user" table="userdata">
          <id name="user_id">
             <generator class="increment"></generator>
          </id>


          <property name="username" column="username" type="string"/>
          <property name="password" column="password" type="string"/>
          <property name="email" column="email" type="string"/>
          <property name="joined" type="timestamp" column="joined"/>

       </class>
    </hibernate-mapping>

hibernate.cfg.xml:

    <?xml version="1.0" encoding="utf-8"?>

   <!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

    <hibernate-configuration>
       <session-factory>
       <property name="hibernate.dialect">
          org.hibernate.dialect.MySQLDialect
       </property>
       <property name="hibernate.connection.driver_class">
          com.mysql.jdbc.Driver
       </property>

       <!-- Assume test is the database name -->
       <property name="hibernate.connection.url">
        jdbc:mysql://localhost/twitter
        </property>
        <property name="hibernate.connection.username">
            root
       </property>
       <property name="hibernate.connection.password">
          root
       </property>

       <!-- List of XML mapping files -->
       <mapping resource="userdata.hbm.xml"/>

    </session-factory>
    </hibernate-configuration>

我的数据库是twitter，表名是userdata。 userdata包含user_id(int，主键，自增)，joined(时间戳)，用户名，电子邮件，密码。谁能告诉我错误是什么？非常感谢!

Answer 1

hibernate 配置文件中的 DTD 声明不正确。

在 user.hbm.xml 文件中，它应该是:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
 "-//Hibernate/Hibernate Mapping DTD//EN"
 "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

对于 hibernate.cfg.xml 文件，它应该是:

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

完成这些更改后，请确保在运行 UserManager 程序时它们位于类路径中。