Struts2：类型转换之批量封装Set集合类型的属性

来源：互联网发布：淘宝网英雄联盟代练编辑：程序博客网时间：2024/06/05 13:34

这个应该是属于Struts2类型转换的话题，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;

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;

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();

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>

</head>

<body>

<s:fielderror />

</div>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</tr>

<tr>

</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：

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。