Spring中集合注入方法

集合注入重要是对数组、List、Set、map的注入，具体注入方法请参照一下代码（重点是applicationContext.xml中对这几个集合注入的方式）：

1.在工程中新建一个Department类，该类包含在com.LHB.collection包当中

 package com.LHB.collection;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
 public class Department {
     private String name;
     private String[] empName;
     private List<Employee> empList;    //List集合
     private Set<Employee> empSets;     //Set集合
     private Map<String,Employee> empMap; //map集合
     private Properties pp;    //Properties的使用

     public Properties getPp() {
         return pp;
     }
     public void setPp(Properties pp) {
         this.pp = pp;
     }
     public Map<String, Employee> getEmpMap() {
         return empMap;
     }
     public void setEmpMap(Map<String, Employee> empMap) {
         this.empMap = empMap;
     }
     public Set<Employee> getEmpSets() {
         return empSets;
     }
     public void setEmpSets(Set<Employee> empSets) {
         this.empSets = empSets;
     }
     public List<Employee> getEmpList() {
         return empList;
     }
     public void setEmpList(List<Employee> empList) {
         this.empList = empList;
     }
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }
     public String[] getEmpName() {
         return empName;
     }
     public void setEmpName(String[] empName) {
         this.empName = empName;
     }
 }

2.继续在包中创建Employee类

 package com.LHB.collection;
 public class Employee {
     private String name;
     private int id;
     public int getId() {
         return id;
     }
     public void setId(int id) {
         this.id = id;
     }
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }

 }

3.创建applicationContext.xml配置文件，配置重点在数组，List，Set，Map，propertes装载值的环节

 <?xml version="1.0" encoding="UTF-8"?>
 <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:context="http://www.springframework.org/schema/context"
        xsi:schemaLocation="http://www.springframework.org/schema/beans
                 http://www.springframework.org/schema/beans/spring-beans.xsd
                 http://www.springframework.org/schema/context
                 http://www.springframework.org/schema/context/spring-context.xsd">

    <bean id="department" class="com.LHB.collection.Department">
        <property name="name" value="财务部门" />
        <!-- 给数组注入值 -->
        <property name="empName">
            <list>
                <value>小米</value>
                <value>小明</value>
                <value>小四</value>
            </list>
        </property>

        <!-- 给list注入值 可以有相同的多个对象  -->
        <property name="empList">
            <list>
                <ref bean="emp1" />
                <ref bean="emp2"/>
            </list>
        </property>
        <!-- 给set注入值 不能有相同的对象 -->
        <property name="empSets">
            <set>
                <ref bean="emp1" />
                <ref bean="emp2"/>
            </set>
        </property>

        <!-- 给map注入值 只要map中的key值不一样就可以装配value -->
        <property name="empMap">
            <map>
                <entry key="1" value-ref="emp1" />
                <entry key="2" value-ref="emp2" />
            </map>
        </property>

        <!-- 给属性集合配置 -->
        <property name="pp">
            <props>
                <prop key="pp1">hello</prop>
                <prop key="pp2">world</prop>
            </props>
        </property>
    </bean>
    <bean id="emp1" class="com.LHB.collection.Employee">
        <property name="name">
            <value>北京</value>
        </property>
    </bean>
     <bean id="emp2" class="com.LHB.collection.Employee">
        <property name="name">
            <value>天津</value>
        </property>
    </bean>

 </beans>

4.继续在该包中新建App1.java测试类

 package com.LHB.collection;
 import java.util.Enumeration;
 import java.util.Iterator;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Properties;

 import org.springframework.context.ApplicationContext;
 import org.springframework.context.support.ClassPathXmlApplicationContext;
 public class App1 {

     public static void main(String[] args) {
         // TODO Auto-generated method stub

         //通过类路径应用上下文获取配置文件applicationContext.xml
         ApplicationContext ac = new ClassPathXmlApplicationContext("com/LHB/collection/applicationContext.xml");
         //通过getBean()获取到applicationContext.xml文件中Bean对象
         Department dm = (Department) ac.getBean("department");
         System.out.println(dm.getName());
         //取出数组中的值
         for(String emName : dm.getEmpName()){
             System.out.println(emName);
         }

         System.out.println("*********通过List集合取出数据******");
         for(Employee e : dm.getEmpList()){
             System.out.println("name = "+ e.getName());
         }

         System.out.println("*********通过Set集合取出数据******");
         for(Employee e : dm.getEmpSets()){
             System.out.println("name = "+ e.getName());
         }

         System.out.println("*********通过Map集合取出数据(迭代器)******");
         //迭代器
         Map<String,Employee> empMap = dm.getEmpMap();
         Iterator it = empMap.keySet().iterator();
         while(it.hasNext()){
             String key = (String) it.next();
             Employee emp = empMap.get(key);
             System.out.println("key = " + key + " " + emp.getName());
         }
         System.out.println("*********通过Map集合取出数据(Emtry简洁法)******");
         //简洁方法
         for(Entry<String,Employee> entry : dm.getEmpMap().entrySet()){

             System.out.println(entry.getKey()+ " " + entry.getValue().getName());
         }

         System.out.println("*********通过Propertis取出数据(通过Entry对象取)******");
         Properties pp = dm.getPp();
         for(Entry<Object,Object> entry : pp.entrySet()){
             System.out.println(entry.getKey().toString() + ", "+ entry.getValue().toString());
         }
         System.out.println("*********通过Propertis取出数据(通过Enumeration对象取)******");
         Enumeration en = pp.keys();
         while(en.hasMoreElements()){
             String key = (String) en.nextElement();
             System.out.println(key + " " + pp.getProperty(key));
         }
     }
 }

运行结果如下：