6.SpringEL与List,Map

SpringEL与List,Map

介绍

使用SpEL与 Map 和 List 的工作方式与Java是完全一样的

//get map whete key = 'MapA'
@Value("#{testBean.map['MapA']}")
private String mapA;//get first value from list, list is 0-based.
@Value("#{testBean.list[0]}")
private String list;

Spring EL以注解的形式

在这里，创建了一个HashMap和ArrayList，并添加了一些初始测试数据

package com.yiibai.core;import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;@Component("customerBean")
public class Customer {@Value("#{testBean.map['MapA']}")private String mapA;@Value("#{testBean.list[0]}")private String list;public String getMapA() {return mapA;}public void setMapA(String mapA) {this.mapA = mapA;}public String getList() {return list;}public void setList(String list) {this.list = list;}@Overridepublic String toString() {return "Customer [mapA=" + mapA + ", list=" + list + "]";}}

package com.yiibai.core;import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.springframework.stereotype.Component;@Component("testBean")
public class Test {private Map<String, String> map;private List<String> list;public Test() {map = new HashMap<String, String>();map.put("MapA", "This is MapA");map.put("MapB", "This is MapB");map.put("MapC", "This is MapC");list = new ArrayList<String>();list.add("List0");list.add("List1");list.add("List2");}public Map<String, String> getMap() {return map;}public void setMap(Map<String, String> map) {this.map = map;}public List<String> getList() {return list;}public void setList(List<String> list) {this.list = list;}}

执行程序

Customer obj = (Customer) context.getBean("customerBean");
System.out.println(obj);

输出结果:

Customer [mapA=This is MapA, list=List0]

Spring EL以XML的形式

<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans-3.0.xsd"><bean id="customerBean" class="com.yiibai.core.Customer"><property name="mapA" value="#{testBean.map['MapA']}" /><property name="list" value="#{testBean.list[0]}" /></bean><bean id="testBean" class="com.yiibai.core.Test" /></beans>