• Hibernate用注解生成表


    User.java实体来
    
    package com.tao.pojo;
    import javax.persistence.Column;
    //用注解的方式生成表
    import javax.persistence.Entity;
    import javax.persistence.GeneratedValue;
    import javax.persistence.GenerationType;
    import javax.persistence.Id;
    import javax.persistence.Table;
    
    import org.hibernate.annotations.GenericGenerator;
    @Entity        //标明当前类是受Hibernate管理的,相当于映射了一个.XML文件    
    @Table(name="User")    //    表名和类名不一致的时候用,table是表名,当前类对应表的名字
    public class User {
        //主键
        @Id
    //    自动增长
        @GeneratedValue(strategy=GenerationType.IDENTITY)
        private int id;
        //column指数据库表中的普通列(不是主键或外键的列),  name里面写列名,当列名和属性名相同的时候,column可以不写,nullable=false 不为空
        @Column(name="name1",length=200,nullable=false)
        private String name;
        private Double money;
        
        public User() {
            super();
        }
        public User(int id, String name, Double money) {
            super();
            this.id = id;
            this.name = name;
            this.money = money;
        }
        public int getId() {
            return id;
        }
        public void setId(int id) {
            this.id = id;
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public Double getMoney() {
            return money;
        }
        public void setMoney(Double money) {
            this.money = money;
        }
        @Override
        public String toString() {
            return "User [id=" + id + ", name=" + name + ", money=" + money + "]";
        }
    }
    
    hibernate.cfg.xml配置文件
    
    <?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>
            <!-- Database connection settings -->
            <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
            <property name="connection.url">jdbc:mysql://localhost:3306/test1123?characterEncoding=utf-8</property>
            <property name="connection.username">root</property>
            <property name="connection.password">root</property>
            <property name="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</property>
            
            <property name="show_sql">true</property>
            <property name="format_sql">true</property>
            <!-- 如果没有就创建,有就更新 -->
            <property name="hibernate.hbm2ddl.auto">update</property>
     
            <mapping class="com.tao.pojo.User"/>
            
        </session-factory>
    
    </hibernate-configuration>
    
    Test001.java测试类
    package com.tao.test;
    import java.util.List;
    import org.hibernate.Session;
    import org.hibernate.SessionFactory;
    import org.hibernate.cfg.Configuration;
    import com.tao.pojo.User;
    
    public class Test001 {
        public static void main(String[] args) {
            Configuration config = new Configuration().configure();
            SessionFactory factory = config.buildSessionFactory();
            Session session = factory.openSession();
            session.beginTransaction();
    //        设置了自动增长之后,这里的Id不起作用,可以不写,按照1,2,3,4,5,的顺序走,如果把,5删了,下一个是6,
            //在创建表的时候先把save屏蔽掉,
    //        User us = new User(32, "啊哈", 32.0);
    //        session.save(us);        
            session.getTransaction().commit();
            session.close();
            factory.close();        
        }
    }
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  • 原文地址:https://www.cnblogs.com/jili6254/p/8244697.html
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