1.hibernate mapping configuration
class tag, used to establish the relationship between classes and tables name: class name, table: table name
id tag , establish the corresponding relationship between the properties in the table and the primary key in the table
property, establish the corresponding relationship between the ordinary properties in the class and the fields of the table
(1) First we must learn how to write mapping Configuration file, everyone must know that the written mapping configuration file should be in the same package as the entity class, and the name should be class name.hbm.xml, so we need to create a Customer under the com.meimeixia.hibernate.demo01 package. hbm.xml file, but how should its constraints be written? You can find the hibernate-mapping-3.0.dtd file under the org.hibernate package of Hibernate's core jar package - hibernate-core-5.0.7.Final.jar.
(2) Copy and paste it into the Customer.hbm.xml file. The content of the Customer.hbm.xml file is given here first, but the content will not be introduced too much:
<?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> <!-- 建立類與表的映射 --> <class name="com.meimeixia.hibernate.demo01.Customer" table="cst_customer"> <!-- 建立類中的屬性與表中的主鍵相對(duì)應(yīng) --> <id name="cust_id" column="cust_id"> <!-- 主鍵的生成策略,后面會(huì)講,現(xiàn)在使用的是本地生成策略 --> <generator /> </id> <!-- 建立類中的普通屬性和表中的字段相對(duì)應(yīng) --> <property name="cust_name" column="cust_name" /> <property name="cust_source" column="cust_source" /> <property name="cust_industry" column="cust_industry" /> <property name="cust_level" column="cust_level" /> <property name="cust_phone" column="cust_phone" /> <property name="cust_mobile" column="cust_mobile" /> </class> </hibernate-mapping>
2.hibernate core configuration
Required configuration: Basic parameters for connecting to the database: driver class, URL path, user name, password, dialect configuration and introduction of mapping files
Optional configuration of displayed SQL statements, formatted SQL statements, and automatic table creation
(1) The core configuration file is mainly used by the Hibernate framework. It mainly contains information related to connecting to the database and Hibernate related configurations. Now we need to learn how to write Hibernate's core configuration file. Everyone must also know that the written core configuration file should be in the src directory, and its name should be hibernate.cfg.xml, so we need to create a hibernate.cfg in the src directory. .xml file, but how should its constraints be written? You can also find the hibernate-configuration-3.0.dtd file
(2) under the org.hibernate package of Hibernate's core jar package - hibernate-core-5.0.7.Final.jar and then copy and paste it. Just go to the hibernate.cfg.xml file. How should it be configured in this file? We can refer to the hibernate-release-5.0.7.Final\project\etc\hibernate.properties file. The content of the hibernate.cfg.xml file is given here first, but the content will not be introduced too much:
<?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> <!-- 下面是三個(gè)必須要有的配置 --> <!-- 配置連接MySQL數(shù)據(jù)庫(kù)的基本參數(shù) --> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <property name="hibernate.connection.url">jdbc:mysql:///hibernate_demo01</property> <property name="hibernate.connection.username">root</property> <property name="hibernate.connection.password">liayun</property> <!-- 配置Hibernate的方言 --> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <!-- 下面兩個(gè)是可選的配置喲! --> <!-- 打印sql語(yǔ)句 --> <property name="hibernate.show_sql">true</property> <!-- 格式化sql語(yǔ)句 --> <property name="hibernate.format_sql">true</property> <!-- 告訴Hibernate的核心配置文件加載哪個(gè)映射文件 --> <mapping resource="com/meimeixia/hibernate/demo01/Customer.hbm.xml"/> </session-factory> </hibernate-configuration>
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