Struts2教學 » Struts2+Hibernate整合範例

Struts2+Hibernate整合範例

在 Struts2 中，沒有官方的外掛整合Hibernate框架。但是，可以通過以下步驟解決方法：
  1. 註冊一個自定義的 ServletContextListener
  2. 在 ServletContextListener 類, 初始化Hibernate對談，並將其儲存到servlet上下文。
  3. 在動作類, 可以通過servlet上下文的Hibernate對談，並執行任務正常的Hibernate操作。
請參閱它們的關係： 
Struts 2 <-- (Servlet Context) ---> Hibernate <-----> Database  

在本教學中，在Struts中2開發我們顯示了一個簡單的客戶模組(新增和列表功能)，並使用 Hibernate 進行資料庫操作。使用上述部分機制整合(儲存和檢索在servlet上下文Hibernate的Session)。

1. 工程目錄結構

來看看這個完整的專案檔案夾結構。

2. MySQL表結構指令碼

建立一個客戶(customer)表。下面是SQL表指令碼。
CREATE TABLE `customer` (
  `customer_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(45) NOT NULL,
  `address` varchar(255) NOT NULL,
  `create_date` datetime NOT NULL,
  PRIMARY KEY (`customer_id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

4. Hibernate 相關組態

Hibernate的模型和組態的東西。

Customer.java – 建立客戶表對應的一個類。 

package com.yiibai.customer.model;

import java.util.Date;

public class Customer implements java.io.Serializable {

	private Long customerId;
	private String name;
	private String address;
	private Date createdDate;

	//getter and setter methods
}

Customer.hbm.xml – Hibernate對映檔案客戶表。 

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.yiibai.customer.model.Customer" 
	table="customer" catalog="yiibai">

        <id name="customerId" type="java.lang.Long">
            <column name="CUSTOMER_ID" />
            <generator class="identity" />
        </id>
        <property name="name" type="string">
            <column name="NAME" length="45" not-null="true" />
        </property>
        <property name="address" type="string">
            <column name="ADDRESS" not-null="true" />
        </property>
        <property name="createdDate" type="timestamp">
            <column name="CREATED_DATE" length="19" not-null="true" />
        </property>
    </class>
</hibernate-mapping>

hibernate.cfg.xml – Hibernate資料庫組態檔案 

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
  <session-factory>
    <property name="hibernate.bytecode.use_reflection_optimizer">false</property>
    <property name="hibernate.connection.password">password</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/yiibai</property>
    <property name="hibernate.connection.username">root</property>
    <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
    <property name="show_sql">true</property>
    <property name="format_sql">true</property>
    <property name="use_sql_comments">false</property>
    <mapping resource="com/yiibai/customer/hibernate/Customer.hbm.xml" />
  </session-factory>
</hibernate-configuration>

5. Hibernate ServletContextListener

建立一個類 ServletContextListener, 並初始化Hibernate對談，並將其儲存到servlet上下文。

HibernateListener .java 

package com.yiibai.listener;

import java.net.URL;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
 
public class HibernateListener implements ServletContextListener{
 
    private Configuration config;
    private SessionFactory factory;
    private String path = "/hibernate.cfg.xml";
    private static Class clazz = HibernateListener.class;
 
    public static final String KEY_NAME = clazz.getName();

	public void contextDestroyed(ServletContextEvent event) {
	  //
	}
 
	public void contextInitialized(ServletContextEvent event) {
 
	 try { 
	        URL url = HibernateListener.class.getResource(path);
	        config = new Configuration().configure(url);
	        factory = config.buildSessionFactory();
	         
	        //save the Hibernate session factory into serlvet context
	        event.getServletContext().setAttribute(KEY_NAME, factory);
	  } catch (Exception e) {
	         System.out.println(e.getMessage());
	   }
	}
}
在 web.xml 檔案中註冊監聽器。

web.xml 

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Struts 2 Web Application</display-name>
  
  <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>
 
  <listener>
    <listener-class>
	  com.yiibai.listener.HibernateListener
    </listener-class>
  </listener>
 
</web-app>

6. Action

在動作類, 可以通過servlet上下文的Hibernate對談和執行正常的Hibernate任務。

CustomerAction.java 

package com.yiibai.customer.action;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.apache.struts2.ServletActionContext;
import org.hibernate.Session;
import org.hibernate.SessionFactory;

import com.yiibai.customer.model.Customer;
import com.yiibai.listener.HibernateListener;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;
 
public class CustomerAction extends ActionSupport 
	implements ModelDriven{

	Customer customer = new Customer();
	List<Customer> customerList = new ArrayList<Customer>();
	
	public String execute() throws Exception {
		return SUCCESS;
	}

	public Object getModel() {
		return customer;
	}
	
	public List<Customer> getCustomerList() {
		return customerList;
	}

	public void setCustomerList(List<Customer> customerList) {
		this.customerList = customerList;
	}

	//save customer
	public String addCustomer() throws Exception{
		
		//get hibernate session from the servlet context
		SessionFactory sessionFactory = 
	         (SessionFactory) ServletActionContext.getServletContext()
                     .getAttribute(HibernateListener.KEY_NAME);

		Session session = sessionFactory.openSession();

		//save it
		customer.setCreatedDate(new Date());
	 
		session.beginTransaction();
		session.save(customer);
		session.getTransaction().commit();
	 
		//reload the customer list
		customerList = null;
		customerList = session.createQuery("from Customer").list();
		
		return SUCCESS;
	
	}
	
	//list all customers
	public String listCustomer() throws Exception{
		
		//get hibernate session from the servlet context
		SessionFactory sessionFactory = 
	         (SessionFactory) ServletActionContext.getServletContext()
                     .getAttribute(HibernateListener.KEY_NAME);

		Session session = sessionFactory.openSession();

		customerList = session.createQuery("from Customer").list();
		
		return SUCCESS;
	
	}	
}

7. JSP 頁面

JSP頁面用來新增和列出的客戶。

customer.jsp 

<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
</head>
 
<body>
<h1>Struts 2 + Hibernate integration example</h1>

<h2>Add Customer</h2>
<s:form action="addCustomerAction" >
  <s:textfield name="name" label="Name" value="" />
  <s:textarea name="address" label="Address" value="" cols="50" rows="5" />
  <s:submit />
</s:form>

<h2>All Customers</h2>

<s:if test="customerList.size() > 0">
<table border="1px" cellpadding="8px">
	<tr>
		<th>Customer Id</th>
		<th>Name</th>
		<th>Address</th>
		<th>Created Date</th>
	</tr>
	<s:iterator value="customerList" status="userStatus">
		<tr>
			<td><s:property value="customerId" /></td>
			<td><s:property value="name" /></td>
			<td><s:property value="address" /></td>
			<td><s:date name="createdDate" format="dd/MM/yyyy" /></td>
		</tr>
	</s:iterator>
</table>
</s:if>
<br/>
<br/>

</body>
</html>

8. struts.xml 

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
 
<struts>
  <constant name="struts.devMode" value="true" />
 	
  <package name="default" namespace="/" extends="struts-default">
		
    <action name="addCustomerAction" 
	class="com.yiibai.customer.action.CustomerAction" method="addCustomer" >
       <result name="success">pages/customer.jsp</result>
    </action>
	
    <action name="listCustomerAction" 
	class="com.yiibai.customer.action.CustomerAction" method="listCustomer" >
        <result name="success">pages/customer.jsp</result>
    </action>		

  </package>	
</struts>

9. 範例測試執行

存取客戶模組：http://localhost:8080/struts2hibernate/listCustomerAction.action

在名稱和地址欄位填寫，點選提交按鈕，插入的客戶的詳細資訊會馬上列出結果。

參考

  1. Struts2 + Hibernate使用「Full Hibernate Plugin"整合
  2. ServletContextListener 文件
  3. Struts + Hibernate整合範例
程式碼下載 - http://pan.baidu.com/s/1hqhQJ7A