SSH

SSH框架的组成

• web层：Struts2
• 业务层：Spring
• 持久层：Hibernate

SSH整合方式

1. 无障碍整合
2. 将hibernate的配置交给Spring管理

无障碍整合

创建web项目，引入jar包

SSH jar包环境下载
在整合之前有必要介绍Struts2的三个重要的包

• struts2-convention-plugin-2.3.24.jar ----Struts2的注解开发包
• struts2-json-plugin-2.3.24.jar ---Sturts2的整合ajax的开发包
• struts2-spring-plugin-2.3.24.jar ---Sturts2整合Spring的开发包

配置文件

1. struts2相关配置
   web.xml配置struts2的核心过滤器

   	<filter>
           <filter-name>struts2filter-name>
           <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilterfilter-class>
       filter>
       <filter-mapping>
           <filter-name>struts2filter-name>
           <url-pattern>/*url-pattern>
       filter-mapping>
   

   struts.xml配置（注意：struts.xml必须放在src根目录下面）

   
   
   <struts>
       
   struts>
   

2. Hibernate配置文件(hibernate.cfg.xml也放在src根目录下)

   • 配置数据库的四个基本参数
   • 配置打印sql语句和格式化sql语句
   • 配置hibernate方言
   • 配置c3p0数据库连接池

   	
   	
   	<hibernate-configuration>
   	    <session-factory>
   	        
   	        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driverproperty>
   	        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/demo39property>
   	        <property name="hibernate.connection.username">rootproperty>
   	        <property name="hibernate.connection.password">cqrjxk39property>
   	        
   	        <property name="hibernate.show_sql">trueproperty>
   	        
   	        <property name="hibernate.format_sql">trueproperty>
   	        
   			<property name="connection.provider_class">org.hibernate.c3p0.internal.C3P0ConnectionProviderproperty>
       		<property name="c3p0.min_size">5property>
       		<property name="c3p0.max_size">20property>
       		<property name="c3p0.timeout">120property>
       		<property name="c3p0.idle_test_period">3000property>
   	        
   	        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialectproperty>
   	    session-factory>
   	hibernate-configuration>
   

3. Spring相关配置（applicationContext.xml放在src根目录下）

   • 注解扫描
   • Spring 对 Hibernate 的整合
   • 开启Hibernate的事务注解

   	
   	<beans xmlns="http://www.springframework.org/schema/beans"
      					xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      					xmlns:context="http://www.springframework.org/schema/context"
      					xmlns:tx="http://www.springframework.org/schema/tx"
      					xsi:schemaLocation="http://www.springframework.org/schema/beans
   					http://www.springframework.org/schema/beans/spring-beans.xsd
   					http://www.springframework.org/schema/context
   					http://www.springframework.org/schema/context/spring-context.xsd
   					http://www.springframework.org/schema/tx
   					http://www.springframework.org/schema/tx/spring-tx.xsd">
   
   		<context:component-scan base-package="com.xhx">context:component-scan>
   
   
   		
   		
   		<bean id="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
   			
   			<property name="configLocation" value="classpath:hibernate.cfg.xml"/>
   		bean>
   		
   		<bean id="transactionManager" class="org.springframework.orm.hibernate5.HibernateTransactionManager">
   			<property name="sessionFactory" ref="sessionFactory">property>
   		bean>
   
   		<tx:annotation-driven transaction-manager="transactionManager">tx:annotation-driven>
   		
   	beans>
   
   

   web.xml配置Spring的监听器

   	<listener>
           <listener-class>org.springframework.web.context.ContextLoaderListenerlistener-class>
       listener>
   

代码编写（一套action -> service -> dao）

action

1. 创建 action 并继承 ActionSupport 且实现 ModelDriven 接口， ModelDriven 的泛型为页面传过来的值的类型，重写 getModel() 方法
2. 加上注解 @Controller 和 @Scope(“prototype”) ， 将类交给Spring管理，并设置为多例
3. 注入你需要的 service 和实体类
4. 在struts.xml配置中配置对应的action

import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;

@Controller
@Scope("prototype")
public class CustomerAction extends ActionSupport implements ModelDriven<Customer> {
    @Autowired
    private Customer customer;

    @Autowired
    private CustomerService customerService;

    @Override
    public Customer getModel() {
        return customer;
    }

    public String save(){
        customerService.save(customer);
        System.out.println("Action中的save执行了");
        return NONE;
    }
}

	<package name="ss1" extends="struts-default" namespace="/">
		
		<action name="customer_*" class="customerAction" method="{1}">action>
	package>

service

添加注解 @Service 将 service 交给 Spring 管理，并添加事务注解 @Transactional

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

@Service
@Transactional
public class CustomerServiceImpl implements CustomerService {

    @Autowired
    private CustomerDao customerDao;

    @Override
    public void save(Customer customer) {
        customerDao.save(customer);
        System.out.println("调用service");
    }
}

dao

1. 创建 dao 并继承 HibernateDaoSupport 类
2. 添加注解 @Repository 将 dao 交给 Spring 管理
3. 调用父类 HibernateDaoSupport 的方法 getHibernateTemplate() 去调用Hibernate的保存方法
4. 在applicationContext中配置dao

import org.springframework.orm.hibernate5.support.HibernateDaoSupport;

public class CustomerDaoImpl extends HibernateDaoSupport implements CustomerDao {

    @Override
    public void save(Customer customer) {
        System.out.println("dao中的save方法执行了");
        this.getHibernateTemplate().save(customer);
    }
}

	<bean id="customerDaoImpl" class="com.xhx.dao.impl.CustomerDaoImpl">
		<property name="sessionFactory" ref="sessionFactory">property>
	bean>

不带hibernate配置文件的整合

1. 创建db.properties文件，将数据库基本信息写入配置中
2. applicationContext引入db.properties文件
3. 配置c3p0数据库连接池
4. 配置hibernate相关的属性和映射文件

	<context:property-placeholder location="classpath:db.properties">context:property-placeholder>
	
	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
		<property name="driverClass" value="${jdbc.driverClass}" />
		<property name="jdbcUrl" value="${jdbc.url}" />
		<property name="user" value="${jdbc.username}" />
		<property name="password" value="${jdbc.passoword}" />
		<property name="maxPoolSize" value="${jdbc.maxPoolSize}" />
		<property name="minPoolSize" value="${jdbc.minPoolSize}" />
		<property name="idleConnectionTestPeriod" value="${jdbc.idleConnectionTestPeriod}" />
	bean>

	
	
	<bean id="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
		<property name="dataSource" ref="dataSource" />
		<property name="hibernateProperties">
			<props>
				<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialectprop>
				<prop key="hibernate.show_sql">trueprop>
				<prop key="hibernate.format_sql">trueprop>
				<prop key="hibernate.hbm2ddl.auto">updateprop>
			props>
		property>
		
		<property name="mappingResources">
			<list>
				<value>com/xhx/pojo/Customer.hbm.xmlvalue>
			list>
		property>
	bean>

Hibernate模板的使用

• 保存

  	public void save(Customer customer) {
          this.getHibernateTemplate().save(customer);
      }
  

• 修改

  	public void update(Customer customer) {
          this.getHibernateTemplate().update(customer);
      }
  

• 删除

  	public void delete(Customer customer) {
          this.getHibernateTemplate().delete(customer);
      }
  

• 通过id查询一个

  	public Customer findById(Long cust_id) {
          Customer customer = this.getHibernateTemplate().load(Customer.class, cust_id);
          return customer;
      }
  

• 查询所有

  	//方法一
  	public List<Customer> findAllByHQL() {
          List<Customer> customers = (List<Customer>)this.getHibernateTemplate().find("from Customer");
          return customers;
      }
      //方法二
      public List<Customer> findAllByQBC() {
          DetachedCriteria criteria = DetachedCriteria.forClass(Customer.class);
          List<Customer> customers = (List<Customer>)this.getHibernateTemplate().findByCriteria(criteria);
          return customers;
  	}
  

• 分页

  	public List<Customer> findAllpage(int nowPage, int pageSize) {
          DetachedCriteria criteria = DetachedCriteria.forClass(Customer.class);
          //nowPage为开头的记录，数据库的记录从0开始，pageSize为一页展示多少条记录
          List<Customer> customers = (List<Customer>)this.getHibernateTemplate().findByCriteria(criteria, nowPage, pageSize);
          return customers;
      }
  

延迟加载的解决方案

在SHH整合开发中哪些地方会出现延迟加载

• 使用load方法查询某一个对象的时候（不常用）
• 查询某个对象后，显示其关联对象（重点）

延迟加载会报出下面的 no Session 异常：

Spring提供的延迟加载的解决方案

在web.xml中配置OpenSessionInViewFilter过滤器，注意：此过滤器必须放在Struts2.xml核心过滤器StrutsPrepareAndExecuteFilter的前面

	<filter>
        <filter-name>OpenSessionInViewFilterfilter-name>
        <filter-class>org.springframework.orm.hibernate5.support.OpenSessionInViewFilterfilter-class>
    filter>
    <filter-mapping>
        <filter-name>OpenSessionInViewFilterfilter-name>
        <url-pattern>*.actionurl-pattern>
    filter-mapping>