在一个简单的 Maven 休眠项目中获取错误"java.lang.NoClassDefFoundError: org/hibernate/cfg/Mappings"

Question

我正在使用maven，hibernate和mysql进行一个项目。这是我的绒球.xml：

<?xml version="1.0" encoding="UTF-8"?>
<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.heroku.realstate</groupId>
    <artifactId>realstate-database</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.38</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.1.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>5.1.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>ejb3-persistence</artifactId>
            <version>1.0.2.GA</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-tools</artifactId>
            <version>4.3.2.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-annotations</artifactId>
            <version>3.5.6-Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-commons-annotations</artifactId>
            <version>3.2.0.Final</version>
        </dependency>
    </dependencies>
</project>

这是我的资源/休眠.cfg.xml：

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.connection.driver_class">
            com.mysql.jdbc.Driver
        </property>
        <property name="hibernate.connection.url">
            jdbc:mysql://localhost:3306/$DATABASE_NAME
        </property>
        <property name="hibernate.connection.password">
            $PASSWORD
        </property>
        <property name="hibernate.connection.username">
            @USERNAME
        </property>
        <property name="hibernate.dialect">
            org.hibernate.dialect.MySQLDialect
        </property>
        <property name="show_sql">
            true
        </property>
        <property name="hbm2ddl.auto">
            create
        </property>
        <mapping class="com.heroku.realstate.database.user.UserEntity"/>
        <mapping class="com.heroku.realstate.database.user.ClientEntity"/>
        <mapping class="com.heroku.realstate.database.user.BotEntity"/>
        <mapping class="com.heroku.realstate.database.sms.SmsEntity"/>
    </session-factory>
</hibernate-configuration>

我已经安装了mysql并创建了一个名为$DATABASE_NAME的数据库，但我还没有在数据库中创建任何表（因为我不是SQL专家，我希望hibernate可以为像我这样的人做到这一点！这是我使用休眠的方式：

class HibernateUtils {
    private static final SessionFactory sessionFactory = buildSessionFactory();
    private static SessionFactory buildSessionFactory() {
        // Create the SessionFactory from hibernate.cfg.xml
        return new AnnotationConfiguration().configure(new File("hibernate.cfg.xml")).buildSessionFactory();
    }
    static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
    static void shutdown() {
        // Close caches and connection pools
        getSessionFactory().close();
    }

我通过 maven 构建了这个项目，它成功构建了。但是当我运行应用程序JVM时，给我错误：java.lang.NoClassDefFoundError：org/hibernate/cfg/Mappings在以下行中：

return new AnnotationConfiguration().configure(new File("hibernate.cgf.xml")).buildSessionFactory();

问题出在哪里？我应该如何解决它？谢谢！

Answer 1

库的问题。您使用 Hibernate 5。所以你不需要这个pom.xml

        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>ejb3-persistence</artifactId>
            <version>1.0.2.GA</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-annotations</artifactId>
            <version>3.5.6-Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-commons-annotations</artifactId>
            <version>3.2.0.Final</version>
        </dependency>

Hibernate 5 使用 hibernate-commons-annotations-5.0.1.Final.jar，您无需指定它。因为，它是一种传递依赖关系。

你也不需要它，因为你不使用JPA

   <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>5.1.0.Final</version>
   </dependency>

在Hibernate 4和Hibernate 5中没有AnnotationConfiguration。它是冬眠3的形式！

配置休眠 5

 private static SessionFactory buildSessionFactory() {
    return new Configuration().configure().buildSessionFactory();
 }

Answer 2

尝试替换此行：

  return new AnnotationConfiguration().configure(new File("hibernate.cgf.xml")).buildSessionFactory();

跟：

   return new Configuration().configure().buildSessionFactory();

因为Deprecated.使用给定应用程序文件中指定的映射和属性。

有关更多信息，请转到注释配置

Answer 3

如果您使用的是版本 3 以上的Hibernate（如构建 4 或 5），只需使用 Configuration 而不是AnnotationConfiguration类，因为版本 3 后AnnotationConfiguration被删除。

让我们有一个包含 11 个依赖项和配置的快照示例，以使用基于注释的映射配置。

1.  antlr-2.7.7.jar
2.  classmate-1.3.0.jar
3.  dom4j-1.6.1.jar
4.  geronimo-jta_1.1_spec-1.1.1.jar
5.  hibernate-commons-annotations-5.0.1.Final.jar
6.  hibernate-core-5.1.10.Final.jar
7.  hibernate-jpa-2.1-api-1.0.0.Final.jar
8.  jandex-2.0.3.Final.jar
9.  javassist-3.20.0-GA.jar
10. jboss-logging-3.3.0.Final.jar
11. mysql-connector-java-5.1.38-bin.jar

配置文件如下：

<hibernate-configuration>
<session-factory>
    <property name="hibernate.connection.driver.class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://zampylob:3306/hibernatedb</property>
    <property name="hibernate.connection.username">hiberuser</property>
    <property name="hibernate.connection.password">XXXXXXXXXX</property>
    <property name="hibernate.connection.dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="hibernate.connection.show_sql">true</property>
    <property name="hibernate.connection.format_sql">true</property>
    <property name="hibernate.hbm2ddl.auto">create</property>
    <mapping class="com.whodesire.model.Student" />
</session-factory>
</hibernate-configuration>

学生POJO课程是：

import java.util.Date;
import javax.persistence.Entity;
import javax.persistence.Id;
@Entity
public class Student {
    @Id
    private Integer rollNo;
    private String firstName;
    private String middleName;
    private String lastName;
    private Date dateOfBirth;
    private String gender;
    public Integer getRollNo() {
        return rollNo;
    }
    public void setRollNo(Integer rollNo) {
        this.rollNo = rollNo;
    }
    public String getFirstName() {
        return firstName;
    }
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    public String getMiddleName() {
        return middleName;
    }
    public void setMiddleName(String middleName) {
        this.middleName = middleName;
    }
    public String getLastName() {
        return lastName;
    }
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    public String getGender() {
        return gender;
    }
    public void setGender(String gender) {
        this.gender = gender;
    }
    public Date getDateOfBirth() {
        return dateOfBirth;
    }
    public void setDateOfBirth(Date dateOfBirth) {
        this.dateOfBirth = dateOfBirth;
    }
}

最后主类是：

SessionFactory factory = new Configuration().configure("resources/hibernate.cfg.xml").buildSessionFactory();
Session session = factory.openSession();
Transaction transaction = session.beginTransaction();
Student student = new Student();
student.setRollNo(1002);
student.setFirstName("Maaherin");
student.setMiddleName("Zubbair");
student.setLastName("Gulfam");
student.setDateOfBirth(new Date());
student.setGender("Male");
session.persist(student);
transaction.commit();
session.close();