Spring(五):Spring&Struts2&Hibernate整合后,实现查询Employee信息
背景:
基于之前两篇文章《Spring(三):Spring整合Hibernate》、《Spring(四):Spring整合Hibernate,之后整合Struts2》,了解了如何整合SSH的过程,但还不知道整合后在项目中该怎么开发使用,本文主要讲解的是基于SSH实现Employee信息查询功能的使用。
新建Employee,Department实体类,并添加对应类的hibernate实体配置文件
新建包com.dx.ssh.entities,在该包下创建Employee、Department实体类,并添加对应的hibernate实体配置文件Employee.hbm.xml、Department.hbm.xml
Employee.java
- package com.dx.ssh.entities;
- public class Department {
- private Integer id;
- private String deparmentName;
- public Integer getId() {
- return id;
- }
- public void setId(Integer id) {
- this.id = id;
- }
- public String getDeparmentName() {
- return deparmentName;
- }
- public void setDeparmentName(String deparmentName) {
- this.deparmentName = deparmentName;
- }
- }
Employee.hbm.xml
- <?xml version="1.0"?>
- <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
- "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
- <!-- Generated 2017-5-9 16:33:32 by Hibernate Tools 3.5.0.Final -->
- <hibernate-mapping>
- <class name="com.dx.ssh.entities.Department" table="SSH_DEPARTMENT">
- <id name="id" type="java.lang.Integer">
- <column name="ID" />
- <generator class="native" />
- </id>
- <property name="deparmentName" type="java.lang.String">
- <column name="DEPARMENTNAME" />
- </property>
- </class>
- </hibernate-mapping>
Department.java
- package com.dx.ssh.entities;
- import java.util.Date;
- public class Employee {
- private Integer id;
- private String lastName;
- private String email;
- private Date birth;
- // 不能被修改
- private Date createTime;
- // n:1的关系
- private Department department;
- public Integer getId() {
- return id;
- }
- public void setId(Integer id) {
- this.id = id;
- }
- public String getLastName() {
- return lastName;
- }
- public void setLastName(String lastName) {
- this.lastName = lastName;
- }
- public String getEmail() {
- return email;
- }
- public void setEmail(String email) {
- this.email = email;
- }
- public Date getBirth() {
- return birth;
- }
- public void setBirth(Date birth) {
- this.birth = birth;
- }
- public Date getCreateTime() {
- return createTime;
- }
- public void setCreateTime(Date createTime) {
- this.createTime = createTime;
- }
- public Department getDepartment() {
- return department;
- }
- public void setDepartment(Department department) {
- this.department = department;
- }
- }
Department.hbm.xml
- <?xml version="1.0"?>
- <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
- "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
- <!-- Generated 2017-5-9 16:33:32 by Hibernate Tools 3.5.0.Final -->
- <hibernate-mapping>
- <class name="com.dx.ssh.entities.Employee" table="SSH_EMPLOYEE">
- <id name="id" type="java.lang.Integer">
- <column name="ID" />
- <generator class="native" />
- </id>
- <property name="lastName" type="java.lang.String">
- <column name="LASTNAME" />
- </property>
- <property name="email" type="java.lang.String">
- <column name="EMAIL" />
- </property>
- <property name="birth" type="java.util.Date">
- <column name="BIRTH" />
- </property>
- <property name="createTime" type="java.util.Date">
- <column name="CREATETIME" />
- </property>
- <!-- 单项N:1关联关系 -->
- <many-to-one name="department" class="com.dx.ssh.entities.Department">
- <column name="DEPARTMENT_ID" />
- </many-to-one>
- </class>
- </hibernate-mapping>
添加Dao、Service、Action,并配置相关配置文件
添加包com.dx.ssh.dao,并新建EmployeeDao.java
- package com.dx.ssh.dao;
- import java.util.List;
- import org.hibernate.Session;
- import org.hibernate.SessionFactory;
- import com.dx.ssh.entities.Employee;
- public class EmployeeDao {
- private SessionFactory sessionFactory;
- public void setSessionFactory(SessionFactory sessionFactory) {
- this.sessionFactory = sessionFactory;
- }
- private Session getSession() {
- return this.sessionFactory.getCurrentSession();
- }
- public List<Employee> getAll() {
- String hql = "From Employee e LEFT OUTER JOIN FETCH e.department";
- return getSession().createQuery(hql).list();
- }
- }
在com.dx.ssh.service包下,新建EmployeeService.java
- package com.dx.ssh.service;
- import java.util.List;
- import com.dx.ssh.dao.EmployeeDao;
- import com.dx.ssh.entities.Employee;
- public class EmployeeService {
- private EmployeeDao employeeDao;
- public void setEmployeeDao(EmployeeDao employeeDao) {
- this.employeeDao = employeeDao;
- }
- public List<Employee> getAll() {
- List<Employee> items = employeeDao.getAll();
- return items;
- }
- }
在com.dx.ssh.actions下,新建Action类EmployeeAction.java
- package com.dx.ssh.service;
- import java.util.List;
- import com.dx.ssh.dao.EmployeeDao;
- import com.dx.ssh.entities.Employee;
- public class EmployeeService {
- private EmployeeDao employeeDao;
- public void setEmployeeDao(EmployeeDao employeeDao) {
- this.employeeDao = employeeDao;
- }
- public List<Employee> getAll() {
- List<Employee> items = employeeDao.getAll();
- return items;
- }
- }
配置applicationContext-beans.xml
- <?xml version="1.0" encoding="UTF-8"?>
- <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
- <bean id="employeeDao" class="com.dx.ssh.dao.EmployeeDao">
- <property name="sessionFactory" ref="sessionFactory"></property>
- </bean>
- <bean id="employeeService" class="com.dx.ssh.service.EmployeeService">
- <property name="employeeDao" ref="employeeDao"></property>
- </bean>
- <bean id="employeeAction" class="com.dx.ssh.actions.EmployeeAction" scope="prototype">
- <property name="employeeService" ref="employeeService"></property>
- </bean>
- </beans>
配置struts.xml
- <?xml version="1.0" encoding="UTF-8" ?>
- <!DOCTYPE struts PUBLIC
- "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
- "http://struts.apache.org/dtds/struts-2.3.dtd">
- <struts>
- <constant name="struts.enable.DynamicMethodInvocation" value="false" />
- <constant name="struts.devMode" value="true" />
- <package name="default" namespace="/" extends="struts-default">
- <action name="emp-*" class="employeeAction" method="{1}">
- <result name="list">/WEB-INF/views/emp-list.jsp</result>
- </action>
- </package>
- </struts>
applicationContext.xml
- <?xml version="1.0" encoding="UTF-8"?>
- <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" 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/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
- http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd
- http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd">
- <!-- 加载配置文件 -->
- <context:property-placeholder location="classpath:jdbc.properties" file-encoding="utf-8" ignore-unresolvable="true" />
- <!-- 配置数据源 -->
- <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
- <property name="driverClass" value="${jdbc.driverClassName}"></property>
- <property name="jdbcUrl" value="${jdbc.url}"></property>
- <property name="user" value="${jdbc.username}"></property>
- <property name="password" value="${jdbc.password}"></property>
- <property name="testConnectionOnCheckout" value="${jdbc.c3p0.testConnectionOnCheckout}"></property>
- <property name="testConnectionOnCheckin" value="${jdbc.c3p0.testConnectionOnCheckin}"></property>
- <property name="idleConnectionTestPeriod" value="${jdbc.c3p0.idleConnectionTestPeriod}"></property>
- <property name="initialPoolSize" value="${jdbc.c3p0.initialPoolSize}"></property>
- <property name="minPoolSize" value="${jdbc.c3p0.minPoolSize}"></property>
- <property name="maxPoolSize" value="${jdbc.c3p0.maxPoolSize}"></property>
- <property name="maxIdleTime" value="${jdbc.c3p0.maxIdleTime}"></property>
- </bean>
- <bean id="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">
- <!-- 数据源dataSource -->
- <property name="dataSource" ref="dataSource" />
- <!-- hibernate的配置方案一 -->
- <property name="configLocation" value="classpath:hibernate.cfg.xml"></property>
- <!-- hibernate的配置方案二 -->
- <!--
- <property name="hibernateProperties">
- <props>
- <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
- <prop key="hibernate.dialect">${hibernate.dialect}</prop>
- <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
- <prop key="hibernate.format_sql">${hibernate.format_sql}</prop>
- <prop key="hibernate.temp.use_jdbc_metadata_defaults">false</prop>
- </props>
- </property>
- -->
- <!-- 持久化类的位置方案一,通过包进行扫描 -->
- <property name="mappingLocations" value="classpath:com/dx/ssh/entities/*.hbm.xml"></property>
- <!-- spring的spring.jar的jar包内,在org.springframework.orm.hibernate3.annotation下,
- 有一个AnnotationSessionFactoryBean类,其中有一个属性叫做"packagesToScan", 有个方法叫setpackagesToScan(),
- 也就是说我可以再spring里面将这个属性给设定上。
- packagesToScan是"包扫描"的意思,哪些包spring可以给我们扫描一下,看看有哪些实体类,
- 这一项在我们在配置文件中配置hibernate的实体类的时候可以这么配,只要给出具体的扫描范围就可以了,
- 不需要将实体类一个一个的写出来
- -->
- <!-- 持久化类的位置方案二,通过包进行扫描 -->
- <!--
- <property name="packagesToScan">
- <list>
- <value>com.dx.ssh.entities</value>
- </list>
- </property>
- -->
- <!-- 持久化类的位置方案三,通过类进行扫描 -->
- <!--
- <property name="annotatedClasses">
- <list>
- <value>com.dx.ssh.entities.Member</value>
- <value>com.dx.ssh.entities.Log</value>
- </list>
- </property>
- -->
- </bean>
- <!-- 配置Hibernate事务管理器 -->
- <bean id="transactionManager" class="org.springframework.orm.hibernate5.HibernateTransactionManager">
- <property name="sessionFactory" ref="sessionFactory" />
- </bean>
- <!-- 配置事务异常封装
- <bean id="persistenceExceptionTranslationPostProcessor" class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor" />
- -->
- <!-- 基于数据源的事务管理器 -->
- <!--
- <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
- <property name="dataSource" ref="dataSource"></property>
- </bean>
- -->
- <!-- 启用注解来管理事务 -->
- <!-- 配合<tx:advice>和<aop:advisor>完成了事务切面的定义 -->
- <!-- 使用强大的切点表达式是语言轻松定义目标方法 -->
- <aop:config proxy-target-class="true">
- <!-- 通过aop定义事务增强切面 -->
- <aop:pointcut expression=" execution(* com.dx.ssh.service..*(..))" id="serviceMethod" />
- <!-- 引用事务增强 -->
- <aop:advisor advice-ref="txAdvice" pointcut-ref="serviceMethod" />
- </aop:config>
- <!-- 事务增强 -->
- <tx:advice id="txAdvice" transaction-manager="transactionManager">
- <!-- 事务属性定义 -->
- <tx:attributes>
- <tx:method name="*" />
- </tx:attributes>
- </tx:advice>
- <!-- 第一种方式: 注解方式配置事物
- <tx:annotation-driven transaction-manager="transactionManager" />
- -->
- </beans>
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>
- <!--
- 把一下配置信息转移到jdbc.properties中。
- <property name="hibernate.connection.username">root</property>
- <property name="hibernate.connection.password">123456</property>
- <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
- <property name="hibernate.connection.url">jdbc:mysql://localhost/my_ssh</property>
- -->
- <property name="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</property>
- <property name="hibernate.show_sql">true</property>
- <property name="hibernate.format_sql">true</property>
- <property name="hibernate.hbm2ddl.auto">update</property>
- <!-- <property name="hibernate.current_session_context_class">thread</property> -->
- </session-factory>
- </hibernate-configuration>
jdbc.properties
- #-----------------------------------------------------
- # \u6570\u636E\u5E93\u914D\u7F6E
- #-----------------------------------------------------
- #\u670D\u52A1\u5668\u5730\u5740
- host=127.0.0.1
- dbName=my_ssh
- jdbc.driverClassName=com.mysql.jdbc.Driver
- jdbc.url=jdbc:mysql://${host}:3306/${dbName}
- jdbc.username=root
- jdbc.password=123456
- #-----------------------------------------------------
- # \u9002\u7528\u4E8Ec3p0\u7684\u914D\u7F6E
- #-----------------------------------------------------
- #-----------------------------------------------------
- # c3p0\u53CD\u7A7A\u95F2\u8BBE\u7F6E\uFF0C\u9632\u6B628\u5C0F\u65F6\u5931\u6548\u95EE\u989828800
- #-----------------------------------------------------
- #idleConnectionTestPeriod\u8981\u5C0F\u4E8EMySQL\u7684wait_timeout
- jdbc.c3p0.testConnectionOnCheckout=false
- jdbc.c3p0.testConnectionOnCheckin=true
- jdbc.c3p0.idleConnectionTestPeriod=3600
- #-----------------------------------------------------
- # c3p0\u8FDE\u63A5\u6C60\u914D\u7F6E
- #-----------------------------------------------------
- #initialPoolSize, minPoolSize, maxPoolSize define the number of Connections that will be pooled.
- #Please ensure that minPoolSize <= maxPoolSize.
- #Unreasonable values of initialPoolSize will be ignored, and minPoolSize will be used instead.
- jdbc.c3p0.initialPoolSize=10
- jdbc.c3p0.minPoolSize=10
- jdbc.c3p0.maxPoolSize=100
- #maxIdleTime defines how many seconds a Connection should be permitted to go unused before being culled from the pool.
- jdbc.c3p0.maxIdleTime=3600
- #-----------------------------------------------------
- # hibernate\u8FDE\u63A5\u6C60\u914D\u7F6E
- #-----------------------------------------------------
- hibernate.connection.driverClass=com.mysql.jdbc.Driver
- hibernate.connection.url=jdbc:mysql://${host}:3306/${dbName}
- hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
- hibernate.show_sql=true
- hibernate.format_sql=true
- hibernate.hbm2ddl.auto=update
在WebContent下创建index.jsp
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
- <html>
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- <title>Insert title here</title>
- </head>
- <body>
- <a href="emp-list">Employee List</a>
- </body>
- </html>
在WEB-INF下创建views文件夹,在views下创建emp-list.jsp页面
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <%@taglib prefix="s" uri="/struts-tags"%>
- <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
- <html>
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- <title>Insert title here</title>
- </head>
- <body>
- <s:if test="#request.employees==null || #request.employees.size()==0">
- 暂无记录!
- </s:if>
- <s:else>
- <table border="1" cellpadding="10" cellspacing="0">
- <tr>
- <td>ID</td>
- <td>LastName</td>
- <td>Email</td>
- <td>BirthDay</td>
- <td>CreateTime</td>
- <td>Department Name</td>
- <tr>
- <s:iterator value="#request.employees">
- <tr>
- <td>${id }</td>
- <td>${lastName }</td>
- <td>${email }</td>
- <td>${birth }</td>
- <td>${createTime }</td>
- <td>${department.deparmentName }</td>
- <tr>
- </s:iterator>
- </table>
- </s:else>
- </body>
- </html>
web.xml
- <?xml version="1.0" encoding="UTF-8"?>
- <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID"
- version="3.0">
- <display-name>My-SSH</display-name>
- <welcome-file-list>
- <welcome-file>index.jsp</welcome-file>
- <welcome-file>index</welcome-file>
- </welcome-file-list>
- <!-- 配置启动IOC容器的Listener -->
- <!-- needed for ContextLoaderListener -->
- <context-param>
- <param-name>contextConfigLocation</param-name>
- <param-value>classpath:applicationContext*.xml</param-value>
- </context-param>
- <!-- Bootstraps the root web application context before servlet initialization -->
- <listener>
- <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
- </listener>
- <!-- Struts2 filter -->
- <filter>
- <filter-name>struts2</filter-name>
- <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
- </filter>
- <filter-mapping>
- <filter-name>struts2</filter-name>
- <url-pattern>/*</url-pattern>
- </filter-mapping>
- </web-app>
项目结构如下:
测试结果:
常见抛出异常情况:
1、nested exception is java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException
错误原因:缺少aspectjweaver-1.8.9.jar包导致的错误。
从地址http://repo1.maven.org/maven2/org/aspectj/aspectjweaver/,下载包aspectjweaver-1.8.9.jar。
2、Action class [userAction] not found - action
在做一个 ssh三个框架集成的时候,经常遇到上诉问题。如果已经正确定义了action,仍报错,其实是缺少包struts2-sping-plugin 2.0.1.jar
解决方案一:
上诉问题说的 在struts.xml 没用找到 sping配置文件里的一个bean啊;也就是说:struts.xml 这个文件没有和sping配置文件关联起来;
在此 另一种解决方案是 在 lib 目录下加入一个jar包struts2-sping-plugin 2.0.1.jar问题就解决了.
解决方案二:
在struts.xml中还要加入这么一个bean
<bean type="com.opensymphony.xwork2.ObjectFactory" name="spring"
class="org.apache.struts2.spring.StrutsSpringObjectFactory" />
这个bean要放在package的外面
3、Struts Problem Report
Struts has detected an unhandled exception:
Messages: |
|
File: | org/hibernate/context/internal/ThreadLocalSessionContext.java |
Line number: | 351 |
解决方案:
包hibernate.cfg.xml中的配置项注意掉:
- <!-- <property name="hibernate.current_session_context_class">thread</property> -->
4、hibernate中采用了lazy加载,在查询hql=“From Employee e”,执行过程中dao被service调用,当action调用employeeService结束后,就立即关闭了session,导致页面没有版本加载数据导致的错误。
Struts has detected an unhandled exception:
Messages: |
|
File: | org/hibernate/proxy/AbstractLazyInitializer.java |
Line number: | 146 |
解决该错误有三种解决方案:
解决方案一:修改Employee.hbm.xml man-to-one节点添加上属性 lazy="false",比较笨的方法。因为这是在用效率作为代价。
- <!-- 单项N:1关联关系 -->
- <many-to-one name="department" class="com.dx.ssh.entities.Department" lazy="false">
- <column name="DEPARTMENT_ID" />
- </many-to-one>
解决方案二:使用OpenSessionInViewFilter。这种方法是将session交给servlet filter来管理,每当一个请求来之后就会开
启一个session,只有当响应结束后才会关闭。如下:
- <filter-name>hibernateFilter</filter-name>
- <filter-class> org.springframework.orm.hibernate3.support.OpenSessionInViewFilter </filter-class>
- </filter
- <filter-mapping>
- <filter-name>hibernateFilter</filter-name>
- <url-pattern>/*</url-pattern>
- </filter-mapping>
解决方案三:修改hql
- public List<Employee> getAll() {
- String hql = "From Employee e LEFT OUTER JOIN FETCH e.department";
- return getSession().createQuery(hql).list();
- }
My-SSH项目源代码下载地址:http://pan.baidu.com/s/1o87Ezge
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