Struts2：类型转换之批量封装Set集合类型的属性

文章出处：http://www.diybl.com/course/3_program/java/javajs/2007927/74827_4.html
本篇主要是讨论如何将页面上表单的值批量封装到一个Set集合中去，因为项目中用的是Hibernate，基本上所有的集合类型用的都是Set类型。至于如何批量封装数据到其它的集合类型如(List，Map)可以参看这篇文章，说的很详细了：http://hi.baidu.com/wava/blog/item/01d58926c42dac158b82a134.html。如何给这个Set属性赋值花费了我相当的时间，下面直接贴例子吧。
CustomerInserterAction.java：处理请求，含有一个Set类型的属性orders

package test.web; 
  
import java.util.HashSet; 
import java.util.List; 
import java.util.Set; 
  
import test.persistence.Customer; 
import test.persistence.Order; 
import test.service.ICustomerService; 
  
import com.opensymphony.xwork2.ActionSupport; 
import com.opensymphony.xwork2.ActionContext; 
  
/** 
 * @author zhukai 2007-8-31 
 *  
 */ 
public class CustomerInserterAction extends ActionSupport { 
    private Customer customer; 
  
    private Set<Order> orders=new HashSet(); 
  
    private ICustomerService customerService; 
  
    public Customer getCustomer() { 
       return customer; 
    } 
  
    public void setCustomer(Customer customer) { 
       //customer.setOrders(orders); 
       this.customer = customer; 
    } 
  
    public String execute() { 
       customer.setOrders(orders); 
       for(Order order:orders) 
           order.setCustomer(customer); 
       customerService.addCustomer(customer); 
       return SUCCESS; 
    } 
  
    public Set getOrders() { 
       return orders; 
    } 
  
    public void setOrders(Set orders) { 
       this.orders = orders; 
    } 
  
    public ICustomerService getCustomerService() { 
       return customerService; 
    } 
  
    public void setCustomerService(ICustomerService customerService) { 
       this.customerService = customerService; 
    } 
} 

Customer.java和Order.java：两个实体类，分别代表一个消费者和一个订单，并且一个消费
                         者可以有多个订单，而一个订单只属于一个消费者。

package test.persistence; 
  
import java.io.Serializable; 
import java.util.Date; 
import java.util.HashSet; 
import java.util.Set; 
  
/** 
 * @author zhukai 
 */ 
  
public class Customer implements Serializable {
private Long id; 
  
    private String name; 
  
    private String email; 
  
    private String password; 
  
    private String phone; 
  
    private boolean married; 
  
    private String address; 
  
    private char sex; 
  
    private String description; 
  
    private Date birthday; 
  
    private Date registeredTime; 
  
    private Set orders = new HashSet(); 
  
    /** 
     * hibernate要求持久化类必须提供一个不带参数的默认构造方法 
     */ 
    public Customer() { 
       // TODO Auto-generated constructor stub 
    } 
  
    public Customer(String name) { 
       super(); 
       this.name = name; 
    } 
  
    public Customer(String name, Set orders) { 
       super(); 
       this.name = name; 
       this.orders = orders; 
    } 
  
    public String getAddress() { 
       return address; 
    } 
  
    public void setAddress(String address) { 
       this.address = address; 
    } 
  
    public String getDescription() { 
       return description; 
    } 
  
    public void setDescription(String description) { 
       this.description = description; 
    } 
  
    public Date getBirthday() { 
       return birthday; 
    } 
  
    public void setBirthday(Date birthday) { 
       this.birthday = birthday; 
    } 
  
    public String getEmail() { 
       return email; 
    } 
  
    public void setEmail(String email) { 
       this.email = email; 
    } 
  
    public Long getId() { 
       return id; 
    } 
  
    public void setId(Long id) { 
       this.id = id; 
    } 
    public String getName() { 
       return name; 
    } 
  
    public void setName(String name) { 
       this.name = name; 
    } 
  
    public String getPassword() { 
       return password; 
    } 
  
    public void setPassword(String password) { 
       this.password = password;// 
    } 
  
    public String getPhone() { 
       return phone; 
    } 
public void setPhone(String phone) { 
       this.phone = phone; 
    } 
  
    public Date getRegisteredTime() { 
       return registeredTime; 
    } 
  
    public void setRegisteredTime(Date registeredTime) { 
       this.registeredTime = registeredTime; 
    } 
  
    public char getSex() { 
       return sex; 
    } 
  
    public void setSex(char sex) { 
       this.sex = sex; 
    } 
  
    public Set getOrders() { 
       return orders; 
    } 
  
    public void setOrders(Set orders) { 
       this.orders = orders; 
    } 
  
    public boolean isMarried() { 
       return married; 
    } 
  
    public void setMarried(boolean married) { 
       this.married = married; 
    } 
  
} 

reg.jsp：前台页面，用于输入数据

<%@ page language="java" contentType="text/html; charset=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></title> 
</head> 
<body> 
<div style="color:red"> 
     <s:fielderror /> 
</div> 
<form action="register.action" method="post"> 
<table width="389" border="1" align="center"> 
  <tr> 
    <th height="30" colspan="4" scope="col"></th> 
    </tr> 
  <tr> 
    <td width="65" height="30">姓名</td> 
    <td width="68"><input name="customer.name" type="text" id="customer.name" size="10"></td> 
    <td width="75">电子邮箱</td> 
    <td width="153"><input name="customer.email" type="text" id="customer.email" size="10"></td> 
  </tr> 
  <tr> 
    <td height="30">地址</td> 
    <td><input name="customer.address" type="text" id="customer.address" size="10"></td> 
    <td>电话</td> 
    <td><input name="customer.phone" type="text" id="customer.phone" size="10"></td> 
  </tr> 
  <tr> 
    <td height="30">密码</td> 
    <td><input name="customer.password" type="text" id="customer.address" size="10"></td> 
    <td>性别</td> 
    <td><input name="customer.sex" type="radio" id="customer.sex" size="10" value="M" checked="checked">男&nbsp;<input name="customer.sex" type="radio" id="customer.sex" size="10" value="F">女</td> 
  </tr> 
   <tr> 
    <td height="30">出生日期</td> 
    <td><input name="customer.birthday" type="text" id="customer.address" size="10"></td> 
    <td>注册日期</td> 
    <td><input name="customer.registerTime" type="text" id="customer.phone" size="10"></td> 
  </tr> 
  <tr> 
    <td height="30" colspan="4">订单一</td> 
  </tr> 
  <tr> 
    <td height="30">订单号</td> 
    <td><input name="orders.makeNew[0].orderNumber" type="text"  size="10"></td> 
    <td>配送地址</td> 
    <td><input name="orders.makeNew[0].address" type="text"  size="10"></td> 
  </tr> 
  <tr> 
<td height="30" colspan="4">订单二</td> 
    </tr> 
  <tr> 
    <td height="30">订单号</td> 
    <td><input name="orders.makeNew[1].orderNumber" type="text"  size="10"></td> 
    <td>配送地址</td> 
    <td><input name="orders.makeNew[1].address" type="text"  size="10"></td> 
  </tr> 
  <tr> 
    <td height="30" colspan="4">订单三</td> 
    </tr> 
  <tr> 
    <td height="30">订单号</td> 
    <td><input name="orders.makeNew[2].orderNumber" type="text"  size="10"></td> 
    <td>配送地址</td> 
    <td><input name="orders.makeNew[2].address" type="text"  size="10"></td> 
  </tr> 
  <tr> 
    <td height="30" colspan="4"><input type="submit" value="提交"><input type="reset" value="重置"> </td> 
  </tr> 
  <tr> 
</table> 
  
</form> 
</body> 
</html> 

CustomerInserterAction-conversion.properties：类型转换的配置文件，我的内容如下
    KeyProperty_orders=id
    Element_orders=test.persistence.Order
    CreateIfNull_orders=true
有几个要说明的地方，这时封装Set集合时必须要注意的：
1．CustomerInserterAction.java中对orders必须要初始化，如下所示：
   private Set<Order> orders=new HashSet();
2．在jsp页面中给变量命名时必须要按照如下的格式：
   <input name="orders.makeNew[0].orderNumber" type="text"  size="10">
   必须要使用makeNew运算符，这样ognl才能帮我创建新的对象，否则orders会为空。当时如果集合类型是List，就不必这样，直接name="orders[0].orderNumber"就可以了。
3．在Class-conversion.properties文件中加上KeyProperty_orders=id，这是封装Set时必须的。这个主要是用来设置检索集合中元素时的索引，具体含义可以参看http://wiki.javascud.org/display/ww2cndoc/Type%20Conversion，它里面对类型转换配置文件做了详细的介绍。

文章出处：http://www.diybl.com/course/3_program/java/javajs/2007927/74827_4.html

评论

1 楼 imouse728 2010-07-28  

网友你好，你这套代码不错，但是那个属性文件，我也加上了，为什么仍然不行啊。
那个属性文件需要别的配置，在那个地文加裁的啊？
我的邮箱：[e-mail]
非常期待您的帮助。