SSH入门Spring篇（3）——依赖注入中的集合注入（注入Map、Set、List、Properties）

借用一下上篇博客的购物车类，分别创建类型为Map、Set、List、Properties类型的一个属性。这些属性呢我也不知道应该拿它们来做什么…就拿来实现一样的功能了。

ShoppingCart.java:（分别创建类型为Map、Set、List、Properties类型的一个属性）

package com.homework.bean;

import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

public class ShoppingCart {

	public ShoppingCart() {
		// TODO Auto-generated constructor stub
	}

	private List itemsOrdered;
	private Map itemsOrdered_Map;
	private Set itemsOrdered_Set;
	private Properties pro;

	public List getItemsOrdered() {
		return itemsOrdered;
	}

	public void setItemsOrdered(List itemsOrdered) {
		this.itemsOrdered = itemsOrdered;
	}

	public Map getItemsOrdered_Map() {
		return itemsOrdered_Map;
	}

	public void setItemsOrdered_Map(Map itemsOrdered_Map) {
		this.itemsOrdered_Map = itemsOrdered_Map;
	}

	public Set getItemsOrdered_Set() {
		return itemsOrdered_Set;
	}

	public void setItemsOrdered_Set(Set itemsOrdered_Set) {
		this.itemsOrdered_Set = itemsOrdered_Set;
	}

	public Properties getPro() {
		return pro;
	}

	public void setPro(Properties pro) {
		this.pro = pro;
	}
}

在applicationContext.xml中的配置

<bean id="shoppingCart" class="com.homework.bean.ShoppingCart">
		<property name="itemsOrdered">
			<list>
				<ref bean="itemOrder1" />
				<ref bean="itemOrder2" />
				<!-- 如果是String的list(不用ref对象)
					<value>string1</value>
					<value>string2</value>
				 -->
			</list>
		</property>
		<property name="itemsOrdered_Map">
			<map>
				<entry key ="1" value-ref="itemOrder1"/>
           		<entry key ="2" value-ref="itemOrder2"/>
           		<!-- 如果是String的map
					<entry key="1" value="string1"/>
					<entry key="2" value="string2"/>
				 -->
			</map>
		</property>
		<property name="itemsOrdered_Set">
			<set>
				<ref bean="itemOrder1" />
				<ref bean="itemOrder2" />
				<!-- 如果是String的set
					<value>string1</value>
					<value>string2</value>
				 -->
			</set>
		</property>
		<property name="pro">
			<props>
			<!-- 
				Properties类型的键和值必须都是String类型的!
			 -->
			    <prop key="1">order1</prop>
			    <prop key="2">order2</prop>
			    <prop key="3">order3</prop>
		   </props>
		</property>
	</bean>

测试类中对这些属性的遍历

package com.homework.app;

import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.homework.bean.*;

public class SpringEnvTest {
	public static void main(String[] args) {
		ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
		
		 System.out.println("\n使用list：");
		ShoppingCart cart = (ShoppingCart) ctx.getBean("shoppingCart");
		List<ItemOrder> list = cart.getItemsOrdered();
		for (ItemOrder order : list) {
			System.out.println("书名： "+ order.getItem().getTitle());
			System.out.println("数量：" + order.getNumItems());
		}
		
		System.out.println("\n使用set：");
		Set<ItemOrder> set = cart.getItemsOrdered_Set();
		for (ItemOrder order : set) {
			System.out.println("书名： "+ order.getItem().getTitle());
			System.out.println("数量：" + order.getNumItems());
		}

		System.out.println("\n使用map：");
		Map map = cart.getItemsOrdered_Map();
		for(Object key : map.keySet()){
		    ItemOrder order = (ItemOrder) map.get(key);
		    System.out.println("书名： "+ order.getItem().getTitle());
			System.out.println("数量：" + order.getNumItems());
		}
		
		System.out.println("\n使用properties：");
		Properties prop = cart.getPro();
		for(Object key : prop.keySet()) {
			System.out.println(prop.get(key));		
		}                                   
	}
}