hibernate的入门
1. 什么是hibernate
ORM框架/持久层框架 jdbc的一个框架
ORM（Object Relational Mapping）：对象关系映射。
对象与关系型数据间之间的映射管理框架
通过管理对象来改变数据库中的数据
通过管理对象来操作数据库
优势：跨数据库的无缝移植
2.如何使用hibernate
2.1 添加hibernate相关依赖
1 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 2 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> 3 <modelVersion>4.0.0</modelVersion> 4 <groupId>com.yuan</groupId> 5 <artifactId>T226_hibernate</artifactId> 6 <packaging>war</packaging> 7 <version>0.0.1-SNAPSHOT</version> 8 <name>T226_hibernate Maven Webapp</name> 9 <url>http://maven.apache.org</url> 10 <properties> 11 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 12 <maven.compiler.source>1.8</maven.compiler.source> 13 <maven.compiler.target>1.8</maven.compiler.target> 14 <junit.version>4.12</junit.version> 15 <servlet.version>4.0.0</servlet.version> 16 <hibernate.version>5.3.0.Final</hibernate.version> 17 <mysql.driver.version>5.1.46</mysql.driver.version> 18 </properties> 19 <dependencies> 20 21 <dependency> 22 <groupId>junit</groupId> 23 <artifactId>junit</artifactId> 24 <version>${junit.version}</version> 25 <scope>test</scope> 26 </dependency> 27 28 <dependency> 29 <groupId>javax.servlet</groupId> 30 <artifactId>javax.servlet-api</artifactId> 31 <version>${servlet.version}</version> 32 <scope>provided</scope> 33 </dependency> 34 35 <dependency> 36 <groupId>org.hibernate</groupId> 37 <artifactId>hibernate-core</artifactId> 38 <version>${hibernate.version}</version> 39 </dependency> 40 41 <dependency> 42 <groupId>mysql</groupId> 43 <artifactId>mysql-connector-java</artifactId> 44 <version>${mysql.driver.version}</version> 45 </dependency> 46 </dependencies> 47 <build> 48 <finalName>T226_hibernate</finalName> 49 <plugins> 50 <plugin> 51 <groupId>org.apache.maven.plugins</groupId> 52 <artifactId>maven-compiler-plugin</artifactId> 53 <version>3.7.0</version> 54 <configuration> 55 <source>${maven.compiler.source}</source> 56 <target>${maven.compiler.target}</target> 57 <encoding>${project.build.sourceEncoding}</encoding> 58 </configuration> 59 </plugin> 60 </plugins> 61 </build> 62 </project>
2.2 在resource目录下添加hibernate.cfg.xml(核心配置文件) ，以及添加DTD支持
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE hibernate-configuration PUBLIC 3 "-//Hibernate/Hibernate Configuration DTD 3.0//EN" 4 "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> 5 <hibernate-configuration> 6 <session-factory> 7 <!-- 1. 数据库相关 --> 8 <property name="connection.username">root</property> 9 <property name="connection.password">***</property> 10 <property name="connection.url">jdbc:mysql://localhost:3306/xm_sc?useUnicode=true&characterEncoding=UTF-8 11 </property> 12 <property name="connection.driver_class">com.mysql.jdbc.Driver</property> 13 <property name="dialect">org.hibernate.dialect.MySQLDialect</property> 14 15 <!-- 配置本地事务（No CurrentSessionContext configured!） --> 16 <property name="hibernate.current_session_context_class">thread</property> 17 18 <!-- 2. 调试相关 --> 19 <property name="show_sql">true</property> 20 <property name="format_sql">true</property> 21 22 <!-- 3. 添加实体映射文件 --> 23 <mapping resource="com/yuan/one/entity/User.hbm.xml" /> 24 </session-factory> 25 </hibernate-configuration>
2.2.1 添加DTD支持
添加到hibernate.cfg.xml（连接数据库信息）
1 <!DOCTYPE hibernate-configuration PUBLIC 2 "-//Hibernate/Hibernate Configuration DTD 3.0//EN" 3 "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE hibernate-configuration PUBLIC 3 "-//Hibernate/Hibernate Configuration DTD 3.0//EN" 4 "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"> 5 <hibernate-configuration> 6 <session-factory> 7 <!-- 1. 数据库相关 --> 8 <property name="connection.username">root</property> 9 <property name="connection.password">***</property>//填入MySQL密码 10 <property name="connection.url">jdbc:mysql://localhost:3306/xm_sc?useUnicode=true&characterEncoding=UTF-8 11 </property> // 此处xm_sc改为MySQL数据库 12 <property name="connection.driver_class">com.mysql.jdbc.Driver</property> 13 <property name="dialect">org.hibernate.dialect.MySQLDialect</property> 14 15 <!-- 配置本地事务（No CurrentSessionContext configured!） --> 16 <property name="hibernate.current_session_context_class">thread</property> 17 18 <!-- 2. 调试相关 --> 19 <property name="show_sql">true</property> 20 <property name="format_sql">true</property> 21 22 <!-- 3. 添加实体映射文件 --> 23 <mapping resource="com/yuan/one/entity/User.hbm.xml" /> 24 </session-factory> 25 </hibernate-configuration>
添加到User.hbm.xml（实体映射文件）
1 <!DOCTYPE hibernate-mapping PUBLIC 2 "-//Hibernate/Hibernate Mapping DTD 3.0//EN" 3 "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
实体类属性必须跟name值一样，后面的column必须跟数据库列段一致
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE hibernate-mapping PUBLIC 3 "-//Hibernate/Hibernate Mapping DTD 3.0//EN" 4 "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"> 5 <hibernate-mapping> 6 <!-- 7 class标签中： 8 name：实体类的全路径 9 table：实体类对应数据库中的表 10 id标签： 11 name：实体类中的属性（映射的是表的主键） 12 type：属性对应的类型 13 Column：属性对应的表中的哪一个列段 14 property： 15 name：实体类中的属性（映射的是表的非主键字段） 16 type：属性对应的类型 17 Column：属性对应的表中的哪一个列段 18 19 List list = session.createQuery("from User").list(); 20 1、建模hibernate.cfg.xml对象，从中拿到了com/yuan/one/entity/User.hbm.xml 21 2、建模了User.hbm.xml，拿到了com.yuan.one.entity.User 和 t_hibernate_User 22 3、User user = Class.forName("com.yuan.con.entity.User").newInstance(); 23 Field userNameField = user.getClass("userName"); 24 Field userPwdField = user.getClass("userPwd"); 25 select user_name,user_pwd,real_name,.... 得到数据库对象信息 26 userNameField.set(user,源2); 27 userPwdField.set(user,mima) 28 .... 29 最后user中的所有属性值都有了 30 4、循环上一步操作，最终所有user实列都放入list集合中就是List list 31 --> 32 <class name="com.yuan.one.entity.User" table="t_hibernate_User"> 33 <id name="id" type="java.lang.Integer" column="id"> 34 <generator class="increment" /> 35 </id> 36 <property name="userName" type="java.lang.String" column="user_name"> 37 </property> 38 <property name="userPwd" type="java.lang.String" column="user_pwd"> 39 </property> 40 <property name="realName" type="java.lang.String" column="real_name"> 41 </property> 42 <property name="sex" type="java.lang.String" column="sex"> 43 </property> 44 <property name="birthday" type="java.sql.Date" column="birthday"> 45 </property> 46 <property insert="false" update="false" name="createDatetime" 47 type="java.sql.Timestamp" column="create_datetime"> 48 </property> 49 <property name="remark" type="java.lang.String" column="remark"> 50 </property> 51 </class> 52 53 </hibernate-mapping>
3、使用hibernate实现后台版增删改案列
3.1 创建实体类，实体必须实现Serializable接口
1 package com.yuan.one.entity; 2 3 import java.io.Serializable; 4 import java.sql.Date; 5 import java.sql.Timestamp; 6 7 public class User implements Serializable{ 8 9 private Integer id; 10 private String userName; 11 private String userPwd; 12 private String realName; 13 private String sex; 14 private Date birthday; 15 private Timestamp createDatetime; 16 private String remark; 17 public Integer getId() { 18 return id; 19 } 20 public void setId(Integer id) { 21 this.id = id; 22 } 23 public String getuserName() { 24 return userName; 25 } 26 public void setuserName(String userName) { 27 this.userName = userName; 28 } 29 public String getUserPwd() { 30 return userPwd; 31 } 32 public void setUserPwd(String userPwd) { 33 this.userPwd = userPwd; 34 } 35 public String getRealName() { 36 return realName; 37 } 38 public void setRealName(String realName) { 39 this.realName = realName; 40 } 41 public String getSex() { 42 return sex; 43 } 44 public void setSex(String sex) { 45 this.sex = sex; 46 } 47 public Date getBirthday() { 48 return birthday; 49 } 50 public void setBirthday(Date birthday) { 51 this.birthday = birthday; 52 } 53 public Timestamp getCreateDatetime() { 54 return createDatetime; 55 } 56 public void setCreateDatetime(Timestamp createDatetime) { 57 this.createDatetime = createDatetime; 58 } 59 public String getRemark() { 60 return remark; 61 } 62 public void setRemark(String remark) { 63 this.remark = remark; 64 } 65 @Override 66 public String toString() { 67 return "User [id=" + id + ", userName=" + userName + ", userPwd=" + userPwd + ", realName=" + realName 68 + ", sex=" + sex + ", birthday=" + birthday + ", createDatetime=" + createDatetime + ", remark=" 69 + remark + "]"; 70 } 71 public User(String userName, String userPwd, String realName, String sex, Date birthday, 72 Timestamp createDatetime, String remark) { 73 super(); 74 this.userName = userName; 75 this.userPwd = userPwd; 76 this.realName = realName; 77 this.sex = sex; 78 this.birthday = birthday; 79 this.createDatetime = createDatetime; 80 this.remark = remark; 81 } 82 public User() { 83 super(); 84 // TODO Auto-generated constructor stub 85 } 86 87 88 }
数据库信息
3.2、查询测试（QueryDemo）
1 package com.yuan.one.test; 2 3 import java.util.List; 4 5 import org.hibernate.Session; 6 import org.hibernate.SessionFactory; 7 import org.hibernate.cfg.Configuration; 8 9 /** 10 * hibernate 中的查询案列 11 * @author ly 12 * 13 */ 14 public class QueryDemo { 15 16 public static void main(String[] args) { 17 //对hibernate.cfg.xml进行建模拿到sessionfactory工厂 18 Configuration configuration = new Configuration().configure("/hibernate.cfg.xml"); 19 SessionFactory SessionFactory = configuration.buildSessionFactory(); 20 //通过工厂模式获取到session会话（操作数据库） 21 Session session = SessionFactory.openSession(); 22 //直接操作数据库 23 List list = session.createQuery("from User").list(); 24 for (Object obj : list) { 25 System.out.println(obj); 26 } 27 //关闭资源 28 29 session.close(); 30 } 31 32 33 }
结果：（数据太大不便插图）
Hibernate: select user0_.id as id1_0_, user0_.user_name as user_nam2_0_, user0_.user_pwd as user_pwd3_0_, user0_.real_name as real_nam4_0_, user0_.sex as sex5_0_, user0_.birthday as birthday6_0_, user0_.create_datetime as create_d7_0_, user0_.remark as remark8_0_ from t_hibernate_User user0_ User [id=1, userName=rrr, userPwd=999, realName=null, sex=null, birthday=null, createDatetime=null, remark=null] User [id=2, userName=ls, userPwd=123, realName=李四, sex=男, birthday=2000-11-10, createDatetime=2018-09-29 09:58:13.0, remark=xyz] User [id=3, userName=zzz2, userPwd=123, realName=null, sex=null, birthday=2018-09-29, createDatetime=2018-09-29 10:07:20.0, remark=null] User [id=4, userName=zzz2, userPwd=123, realName=null, sex=null, birthday=2018-10-06, createDatetime=2018-10-06 07:17:54.0, remark=null] User [id=5, userName=bbbb, userPwd=123s, realName=null, sex=null, birthday=null, createDatetime=2018-10-16 16:12:53.0, remark=null] User [id=6, userName=ttttt, userPwd=6666, realName=null, sex=null, birthday=null, createDatetime=2018-10-17 11:46:20.0, remark=null] User [id=7, userName=吃吃吃, userPwd=mima, realName=null, sex=null, birthday=null, createDatetime=2018-10-17 15:01:55.0, remark=null] User [id=9, userName=吃吃吃22, userPwd=mima, realName=null, sex=null, birthday=null, createDatetime=2018-10-17 15:08:45.0, remark=null] User [id=11, userName=xxx, userPwd=123456, realName=xxx, sex=1, birthday=null, createDatetime=2018-11-17 09:47:03.0, remark=xxx] User [id=12, userName=xxx, userPwd=123456, realName=xxx, sex=1, birthday=null, createDatetime=2018-11-17 09:48:17.0, remark=xxx] User [id=13, userName=xxx, userPwd=123456, realName=xxx, sex=1, birthday=2018-11-17, createDatetime=2018-11-17 09:48:48.0, remark=xxx] User [id=14, userName=精华, userPwd=123456, realName=金燕, sex=女, birthday=null, createDatetime=2018-11-18 09:24:38.0, remark=开小差]
3.3新增测试 (AddDemo)
1 package com.yuan.one.test; 2 3 import java.sql.Date; 4 import java.sql.Timestamp; 5 import java.util.List; 6 7 import org.hibernate.Session; 8 import org.hibernate.SessionFactory; 9 import org.hibernate.Transaction; 10 import org.hibernate.cfg.Configuration; 11 12 import com.yuan.one.entity.User; 13 14 /** 15 * hibernate 增加案列 16 * @author ly 17 * 18 */ 19 public class AddDemo { 20 21 public static void main(String[] args) { 22 //对hibernate.cfg.xml进行建模拿到sessionfactory工厂 23 Configuration configuration = new Configuration().configure("/hibernate.cfg.xml"); 24 SessionFactory SessionFactory = configuration.buildSessionFactory(); 25 //通过工厂模式获取到session会话（操作数据库） 26 Session session = SessionFactory.openSession(); 27 //获取事务对象 28 Transaction transaction = session.beginTransaction(); 29 //直接操作数据库 30 session.save(new User("yuan", "123456", "源", "男", new Date(System.currentTimeMillis()), new Timestamp(System.currentTimeMillis()), "暂无介绍")); 31 //提交事务 32 transaction.commit(); 33 //关闭资源 34 35 session.close(); 36 } 37 38 39 }
结果：（数据库显示）
3.4修改测试（EditDemo）
1 package com.yuan.one.test; 2 3 import java.sql.Date; 4 import java.sql.Timestamp; 5 import java.util.List; 6 7 import org.hibernate.Session; 8 import org.hibernate.SessionFactory; 9 import org.hibernate.Transaction; 10 import org.hibernate.cfg.Configuration; 11 12 import com.yuan.one.entity.User; 13 14 /** 15 * hibernate 修改案列 16 * @author ly
17 * 18 */ 19 public class EditDemo { 20 21 public static void main(String[] args) { 22 //对hibernate.cfg.xml进行建模拿到sessionfactory工厂 23 Configuration configuration = new Configuration().configure("/hibernate.cfg.xml"); 24 SessionFactory SessionFactory = configuration.buildSessionFactory(); 25 //通过工厂模式获取到session会话（操作数据库） 26 Session session = SessionFactory.openSession(); 27 //获取事务对象 28 Transaction transaction = session.beginTransaction(); 29 //直接操作数据库 30 //传统用法 31 // User user= new User("yuan2", "123456", "源2", "男", new Date(System.currentTimeMillis()), new Timestamp(System.currentTimeMillis()), "暂无介绍2"); 32 // user.setId(15); 33 // session.update(user); 34 // session.save(); 35 //更改单个列段 36 User user = session.get(User.class, 15); 37 System.out.println(user); 38 user.setRealName("源3"); 39 //提交事务 40 transaction.commit(); 41 //关闭资源 42 43 session.close(); 44 } 45 46 47 }
结果：（更改单个列段效果）
3.5删除测试（DelDemo）
1 package com.yuan.one.test; 2 3 import java.sql.Date; 4 import java.sql.Timestamp; 5 import java.util.List; 6 7 import org.hibernate.Session; 8 import org.hibernate.SessionFactory; 9 import org.hibernate.Transaction; 10 import org.hibernate.cfg.Configuration; 11 12 import com.yuan.one.entity.User; 13 14 /** 15 * hibernate 增加案列 16 * @author ly 17 * 18 */ 19 public class DelDemo { 20 21 public static void main(String[] args) { 22 //对hibernate.cfg.xml进行建模拿到sessionfactory工厂 23 Configuration configuration = new Configuration().configure("/hibernate.cfg.xml"); 24 SessionFactory SessionFactory = configuration.buildSessionFactory(); 25 //通过工厂模式获取到session会话（操作数据库） 26 Session session = SessionFactory.openSession(); 27 //获取事务对象 28 Transaction transaction = session.beginTransaction(); 29 //直接操作数据库 30 User user=new User(); 31 user.setId(15); 32 session.delete(user); 33 //提交事务 34 transaction.commit(); 35 //关闭资源 36 37 session.close(); 38 } 39 40 41 }
结果：（根据id删除）
谢谢观看 ^-^ ！！！
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