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：