Hibernate_01

2022-10-30 08:12:01

*:first-child {
margin-top: 0 !important;
}

body>*:last-child {
margin-bottom: 0 !important;
}

/* BLOCKS
=============================================================================*/

p, blockquote, ul, ol, dl, table, pre {
margin: 15px 0;
}

/* HEADERS
=============================================================================*/

h1, h2, h3, h4, h5, h6 {
margin: 20px 0 10px;
padding: 0;
font-weight: bold;
-webkit-font-smoothing: antialiased;
}

h1 tt, h1 code, h2 tt, h2 code, h3 tt, h3 code, h4 tt, h4 code, h5 tt, h5 code, h6 tt, h6 code {
font-size: inherit;
}

h1 {
font-size: 28px;
color: #000;
}

h2 {
font-size: 24px;
border-bottom: 1px solid #ccc;
color: #000;
}

h3 {
font-size: 18px;
}

h4 {
font-size: 16px;
}

h5 {
font-size: 14px;
}

h6 {
color: #777;
font-size: 14px;
}

body>h2:first-child, body>h1:first-child, body>h1:first-child+h2, body>h3:first-child, body>h4:first-child, body>h5:first-child, body>h6:first-child {
margin-top: 0;
padding-top: 0;
}

a:first-child h1, a:first-child h2, a:first-child h3, a:first-child h4, a:first-child h5, a:first-child h6 {
margin-top: 0;
padding-top: 0;
}

h1+p, h2+p, h3+p, h4+p, h5+p, h6+p {
margin-top: 10px;
}

/* LINKS
=============================================================================*/

a {
color: #4183C4;
text-decoration: none;
}

a:hover {
text-decoration: underline;
}

/* LISTS
=============================================================================*/

ul, ol {
padding-left: 30px;
}

ul li > :first-child,
ol li > :first-child,
ul li ul:first-of-type,
ol li ol:first-of-type,
ul li ol:first-of-type,
ol li ul:first-of-type {
margin-top: 0px;
}

ul ul, ul ol, ol ol, ol ul {
margin-bottom: 0;
}

dl {
padding: 0;
}

dl dt {
font-size: 14px;
font-weight: bold;
font-style: italic;
padding: 0;
margin: 15px 0 5px;
}

dl dt:first-child {
padding: 0;
}

dl dt>:first-child {
margin-top: 0px;
}

dl dt>:last-child {
margin-bottom: 0px;
}

dl dd {
margin: 0 0 15px;
padding: 0 15px;
}

dl dd>:first-child {
margin-top: 0px;
}

dl dd>:last-child {
margin-bottom: 0px;
}

/* CODE
=============================================================================*/

pre, code, tt {
font-size: 12px;
font-family: Consolas, "Liberation Mono", Courier, monospace;
}

code, tt {
margin: 0 0px;
padding: 0px 0px;
white-space: nowrap;
border: 1px solid #eaeaea;
background-color: #f8f8f8;
border-radius: 3px;
}

pre>code {
margin: 0;
padding: 0;
white-space: pre;
border: none;
background: transparent;
}

pre {
background-color: #f8f8f8;
border: 1px solid #ccc;
font-size: 13px;
line-height: 19px;
overflow: auto;
padding: 6px 10px;
border-radius: 3px;
}

pre code, pre tt {
background-color: transparent;
border: none;
}

kbd {
-moz-border-bottom-colors: none;
-moz-border-left-colors: none;
-moz-border-right-colors: none;
-moz-border-top-colors: none;
background-color: #DDDDDD;
background-image: linear-gradient(#F1F1F1, #DDDDDD);
background-repeat: repeat-x;
border-color: #DDDDDD #CCCCCC #CCCCCC #DDDDDD;
border-image: none;
border-radius: 2px 2px 2px 2px;
border-style: solid;
border-width: 1px;
font-family: "Helvetica Neue",Helvetica,Arial,sans-serif;
line-height: 10px;
padding: 1px 4px;
}

/* QUOTES
=============================================================================*/

blockquote {
border-left: 4px solid #DDD;
padding: 0 15px;
color: #777;
}

blockquote>:first-child {
margin-top: 0px;
}

blockquote>:last-child {
margin-bottom: 0px;
}

/* HORIZONTAL RULES
=============================================================================*/

hr {
clear: both;
margin: 15px 0;
height: 0px;
overflow: hidden;
border: none;
background: transparent;
border-bottom: 4px solid #ddd;
padding: 0;
}

/* TABLES
=============================================================================*/

table th {
font-weight: bold;
}

table th, table td {
border: 1px solid #ccc;
padding: 6px 13px;
}

table tr {
border-top: 1px solid #ccc;
background-color: #fff;
}

table tr:nth-child(2n) {
background-color: #f8f8f8;
}

/* IMAGES
=============================================================================*/

img {
max-width: 100%
}
-->

Hibernate

hibernate是一个持久层orm框架，目的：简化项目开发，提高开发效率。

快速入门

下载hibernate，然后导入hibernate->lib->required下面的所有jar包，还有就是数据库驱动的jar包。

创建表cst_customer

CREATE TABLE `cst_customer` (

`cust_id` bigint(32) NOT NULL AUTO_INCREMENT COMMENT '客户编号(主键)',

`cust_name` varchar(32) NOT NULL COMMENT '客户名称(公司名称)',

`cust_source` varchar(32) DEFAULT NULL COMMENT '客户信息来源',

`cust_industry` varchar(32) DEFAULT NULL COMMENT '客户所属行业',

`cust_level` varchar(32) DEFAULT NULL COMMENT '客户级别',

`cust_address` varchar(128) DEFAULT NULL COMMENT '客户联系地址',

`cust_phone` varchar(64) DEFAULT NULL COMMENT '客户联系电话',

PRIMARY KEY (`cust_id`)

) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

创建相应的实体类 Customer.java

  public class Customer implements Serializable {

  private static final long serialVersionUID = 1L;

  private Long id;// 主键

  private String custName;// 客户姓名

  private String custSource; // 客户来源

  private String custIndustry; // 所属行业

  private String custLevel; // 客户级别

  private String custAddress; // 地址

  private String custPhone; // 电话

  public Long getId() {

      return id;

  }

  public void setId(Long id) {

      this.id = id;

  }

  public String getCustName() {

      return custName;

  }

  public void setCustName(String custName) {

      this.custName = custName;

  }

  public String getCustSource() {

      return custSource;

  }

  public void setCustSource(String custSource) {

      this.custSource = custSource;

  }

  public String getCustIndustry() {

      return custIndustry;

  }

  public void setCustIndustry(String custIndustry) {

      this.custIndustry = custIndustry;

  }

  public String getCustLevel() {

      return custLevel;

  }

  public void setCustLevel(String custLevel) {

      this.custLevel = custLevel;

  }

  public String getCustAddress() {

      return custAddress;

  }

  public void setCustAddress(String custAddress) {

      this.custAddress = custAddress;

  }

  public String getCustPhone() {

      return custPhone;

  }

  public void setCustPhone(String custPhone) {

      this.custPhone = custPhone;

  }

  @Override

  public String toString() {

      return "Customer [id=" + id + ", custName=" + custName + ", custSource=" + custSource + ", custIndustry="

              + custIndustry + ", custLevel=" + custLevel + ", custAddress=" + custAddress + ", custPhone="

              + custPhone + "]";

  }

}

创建对应的配置文件 Customer.hbm.xml

<?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>

  <!--

      class标签

      name : 实体类的全限定名

      table : 对应数据库的表名(如果类名和数据库表的名字一样，可以省略table配置)

   -->

  <class name="com.xiaoshitou.domain.Customer" table="cst_customer">

      <!-- id标签：主键

          name ： 实体类中的id

          column : 数据库中主键的名字

       -->

      <id name="id" column="cust_id">

          <!-- gennerator class：主键的生成策略；native表示，主键由数据库自动维护 -->

          <generator class="native"></generator>

      </id>

      <!-- property:主键以外的普通字段

       name=>实体类中的成员变量，column=>表中的字段名  -->

      <property name="custName" column="cust_name"></property>

      <property name="custSource" column="cust_source"></property>

      <property name="custIndustry" column="cust_industry"></property>

      <property name="custLevel" column="cust_level"></property>

      <property name="custAddress" column="cust_address"></property>

      <property name="custPhone" column="cust_phone"></property>

  </class>

</hibernate-mapping>

编写hiberna核心配置文件：一定要放在src目录下，hibernate.cfg.xml

<?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 name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>

      <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate</property>

      <property name="hibernate.connection.username">root</property>

      <property name="hibernate.connection.password">123456</property>

      <!-- 配置数据库方言 -->

      <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>

      <!-- 显示sql -->

      <property name="hibernate.show_sql">true</property>

      <!-- 格式化sql -->

      <property name="hibernate.format">true</property>

      <!-- create-drop:启动时会创建表，sessionFactory关闭时删除表,

          create: 每次都会重新创建表,

          update: 如果实体类和数据库的表字段不一样时，会修改数据库中的字段，保证实体类和数据库表是同步的,

          validate： 如果实体类和数据库表字段不一致时，会报错  -->

      <property name="hibernate.hbm2ddl.auto">update</property>

      <!-- 把实体类的配置文件加载到核心配置文件中 -->

      <mapping resource="com/xiaoshitou/domain/Customer.hbm.xml"/>

  </session-factory>

</hibernate-configuration>

编写测试类，使用hibernate来添加一条数据

/**

   * 快速入门：利用hibernate添加一条数据

   */

  @Test

  public void test01() {

      // 创造一个customer对象

      Customer customer = new Customer();

      customer.setCustName("东方科技");

      customer.setCustLevel("VIP");

      customer.setCustSource("朋友推荐");

      customer.setCustIndustry("无人机");

      customer.setCustAddress("东方1号路");

      customer.setCustPhone("8221365");

      // 利用hibernate完成保存

      Configuration configuration = new Configuration();

      configuration.configure();

      // 创建sessionFactory

      SessionFactory sessionFactory = configuration.buildSessionFactory();

      // 获取session

      Session session = sessionFactory.openSession();

      // 开启事务

      Transaction tx = session.beginTransaction();

      // 保存

      session.save(customer);

      // 提交事务，关闭资源

      tx.commit();

      session.close();

      sessionFactory.close();

  }

hibernate 使用c3p0连接池

导入jar包：hibernate-release-5.0.7.Final\lib\optional\c3p0

在hibernate.cfg.xml中添加配置

<?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>

      <!-- 使用c3p0连接池 -->

      <property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property>

      <!-- 在数据库连接池中，最大连接数 -->

      <property name="hibernate.c3p0.max_size">20</property>

      <!-- 在数据库连接池中，最小连接数 -->

      <property name="hibernate.c3p0.min_size">5</property>

      <!-- 如果连接池中，某个连接空闲时间超过设置的时间，将会被从连接池冲清除 -->

      <property name="hibernate.c3p0.timeout">5000</property>

      <!-- 每个3000秒检查，连接池中的空闲连接,单位秒 -->

      <property name="hibernate.c3p0.idle_test_period">3000</property>

      <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>

      <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate</property>

      <property name="hibernate.connection.username">root</property>

      <property name="hibernate.connection.password">123456</property>

      <!-- 配置数据库方言 -->

      <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>

      <!-- 显示sql -->

      <property name="hibernate.show_sql">true</property>

      <!-- 格式化sql -->

      <property name="hibernate.format_sql">true</property>

      <!-- create-drop:启动时会创建表，sessionFactory关闭时删除表,

          create: 每次都会重新创建表,

          update: 如果实体类和数据库的表字段不一样时，会修改数据库中的字段，保证实体类和数据库表是同步的,

          validate： 如果实体类和数据库表字段不一致时，会报错  -->

      <property name="hibernate.hbm2ddl.auto">update</property>

      <!-- 把实体类的配置文件加载到核心配置文件中 -->

      <mapping resource="com/xiaoshitou/domain/Customer.hbm.xml"/>

  </session-factory>

</hibernate-configuration>

session中的saveOrUpdate方法:

如果对象中没有设置id,就会新增一条记录
如果对象中设置了id,并且数据库中，有对应id的记录，那么就是修改记录
如果对象中设置了id,在数据库中没有对应id的记录，那么将会执行失败，抛出异常。
session中get和load方法的区别
get是立即加载(立即执行sql语句)，load是延迟加载(在真正使用对象的属性时，才会发送sql语句)
get返回的对象是要查询的实体对象，load返回的代理对象

码农公寓

Hibernate

hibernate是一个持久层orm框架，目的：简化项目开发，提高开发效率。

快速入门

hibernate 使用c3p0连接池

session中的saveOrUpdate方法:

session中get和load方法的区别

相关文章