Struts2+Hibernate使用Full Hibernate Plugin集成

在上篇 Struts2 + Hibernate集成實例中, 它使用 servlet 上下文監聽 Hibernate 的 Session，而且把Struts2和Hibernate框架集成。

但是，總有一些東西要提高。在本教程中，我們將展示如何整合Struts2+Hibernate，並使用Struts2一個名為“Full Hibernate Plugin“的插件。

見下麵的集成步驟：

把 “Full Hibernate Plugin” jar 放入到工程類路徑。
使用 “@SessionTarget” 注釋來注入到 Hibernate session; 當“@TransactionTarget” 注釋注入到Hibernate 事務。
在 struts.xml, 讓包擴展 “hibernate-default“，而不是默認的堆疊。

看看下麵的關係：

Struts 2 <-- (Full Hibernate Plugin) ---> Hibernate <-----> Database

注，
本教程是從以前的 Struts2 + Hibernate集成實例(servlet context listener)更新版本。因此，JSP 和 Hibernate 配置基本相同，只是整合的部分是有點不同，嘗試比較既能發現不同。

1. 工程結構

在節教學，我們創建一個工程名為 full-hibernate 的web工程。看看這個專案檔夾的完整結構。

2. MySQL創建表腳本

Customer表結構

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;

3. Hibernate相關配置

所有 Hibernate 的模型和配置的東西。

Customer.java – 為customer 表創建一個類。

package com.zaixian.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 的 customer 表映射。

<?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 20 Julai 2010 11:40:18 AM by Hibernate Tools 3.2.5.Beta -->
<hibernate-mapping>
    <class name="com.zaixian.customer.model.Customer"
		table="customer" catalog="zaixian">
        <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>

檔: hibernate.cfg.xml, Hibernate 資料庫配置

<?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/zaixian</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/zaixian/customer/hibernate/Customer.hbm.xml" />
  </session-factory>
</hibernate-configuration>

5. DAO

實現DAO設計模式執行數據庫操作。在 CustomerDAOImpl 類, 聲明Hibernate會話和事務為類成員。在Struts 2的專案初始化， “Full Hibernate Plugin” 使用 @SessionTarget 和 @TransactionTarget 分別標注將注入相應的 Hibernate 會話和事務成為類成員。

CustomerDAO.java

package com.zaixian.customer.dao;

import java.util.List;

import com.zaixian.customer.model.Customer;

public interface CustomerDAO{

	void addCustomer(Customer customer);

	List<Customer> listCustomer();

}

CustomerDAOImpl.java

package com.zaixian.customer.dao.impl;

import java.util.List;

import org.hibernate.Session;
import org.hibernate.Transaction;

import com.googlecode.s2hibernate.struts2.plugin.annotations.SessionTarget;
import com.googlecode.s2hibernate.struts2.plugin.annotations.TransactionTarget;
import com.zaixian.customer.dao.CustomerDAO;
import com.zaixian.customer.model.Customer;

public class CustomerDAOImpl implements CustomerDAO{

	@SessionTarget
	Session session;

	@TransactionTarget
	Transaction transaction;

	//add the customer
	public void addCustomer(Customer customer){

		session.save(customer);

	}

	//return all the customers in list
	public List<Customer> listCustomer(){

		return session.createQuery("from Customer").list();

	}

}

6. Action

在Action類，調用DAO類來執行數據庫操作。

CustomerAction.java

package com.zaixian.customer.action;

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

import com.zaixian.customer.dao.CustomerDAO;
import com.zaixian.customer.dao.impl.CustomerDAOImpl;
import com.zaixian.customer.model.Customer;
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>();
	CustomerDAO customerDAO = new CustomerDAOImpl();

	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{

		//save it
		customer.setCreatedDate(new Date());
		customerDAO.addCustomer(customer);

		//reload the customer list
		customerList = null;
		customerList = customerDAO.listCustomer();

		return SUCCESS;

	}

	//list all customers
	public String listCustomer() throws Exception{

		customerList = customerDAO.listCustomer();

		return SUCCESS;

	}

}

7. JSP 頁面

JSP頁面添加並列出客戶。

customer.jsp

<%@ taglib prefix="s" uri="/struts-tags" %>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
</head>

<body>
<h1>Struts 2 Full Hibernate Plugin 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

鏈接所有〜讓包擴展 “hibernate-default” 來代替 “struts-default“.

<?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="hibernate-default">

    <action name="addCustomerAction"
	class="com.zaixian.customer.action.CustomerAction" method="addCustomer" >
       <result name="success">pages/customer.jsp</result>
    </action>

    <action name="listCustomerAction"
	class="com.zaixian.customer.action.CustomerAction" method="listCustomer" >
        <result name="success">pages/customer.jsp</result>
    </action>

</package>
</struts>