Hibernate environment construction and demo

1. Download the hibernate
hibernate official website.
2. Import all the jar packages under required and add a package to connect to the database (my database is mysql8.0.13), and the package is finished!
3. To configure, the first step is to create a hibernate.cfg.xml file under src, the name can not be wrong. Then introduce the constraint dtd to this xml file. (This dtd is in the package imported before)
Insert picture description here

Open:

add this paragraph to your hibernate.cfg.xml file

<?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 元素用于配置Hibernate中的属性
            键:值 
          -->
        <property name="hibernate.connection.driver_class">com.mysql.cj.jdbc.Driver</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">321123ww</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/RUNOOB?serverTimezone=UTC</property>
        <!--表示那个数据库的方言org.hibernate.dialect.MySQL8Dialect这一块因为我的mysql是8.0.13所以这块是8-->
 		<property name="hibernate.dialect">org.hibernate.dialect.MySQL8Dialect</property>
 		
 		
 		
 		
        <!-- show_sql: 操作数据库时,会 向控制台打印sql语句 -->
        <property name="show_sql">true</property>
        <!-- format_sql: 打印sql语句前,会将sql语句先格式化  -->
        <property name="format_sql">true</property>
        
		
		
		
		<!-- #4如何创建表(不重要)	 
		create:每一次加载cfg.xml文件都将创建表，程序关闭时，表不进行删除 [初始化，测试时使用]
		如果表存在则先删除后创建
		create-drop:每一次加载cfg.xml文件都将创建表，程序关闭时，表进行删除
		必须执行factory.close()才能删除
		update:如果表不存在则创建，如果表存在，先回检查*.hbm.xml文件是否和表匹配，
		如果不匹配将更新表结构（只添加，不删除）
		validate:加载cfg.xml进效验，映射文件和数据表是否匹配，如果匹配正常操作，如果不匹配则抛出异常
		### 显示的开发中先有的表,再有的映射文件
		* 表 由DBA创建
		-->
		
		<property name="hibernate.hbm2ddl.auto">update</property>
		<!--将线程配置成Thread级别的  -->
		<property name="hibernate.current_session_context_class">thread</property>
		
		<!--绑定orm配置  -->
		<mapping resource="hiubernate/domain/product.hbm.xml"/>
		
    </session-factory>
</hibernate-configuration>

After adding constraints
Insert picture description here
, create entities:

package hiubernate.domain;

public class Product {
    
    
	private String pid;
	private String pname;
	private double p_price;
	private int cid;
	private String eve;
	private String unit;

Create product.hbm.xml at the same level of this class

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

    <class name="Product" table="product_copy2">
    
        <id name="pid" column="pid"  >
        <!--数据库id和表的id -->
            <generator class="uuid" />  <!--uuid是会自动给你一个uid,但是你的id必须为String类型  -->
        </id>
        <!--数据库和domain的对应 -->
        <property name="pname" column="pname"></property>
        <property name="p_price"  column="p_price"></property>
		<property name="cid"  column="cid"></property>
		<property name="eve"  column="eve"></property>
		<property name="unit"  column="unit"></property>
		
 
    </class>
</hibernate-mapping>

This one should also add a dependency, the same as the previous one! ! !
4. Test
Goodbye in advance and fill in the code afterwards! ! ! !

Hibernate environment construction and demo

Guess you like