1 package spring;
 2 
 3 import org.springframework.context.ApplicationContext;
 4 import org.springframework.context.support.ClassPathXmlApplicationContext;
 5 
 6 public class Circle {
 7 
 8     private double radius;
 9     private double peri;
10     private double area;
11 
12     public double getRadius() {
13         return radius;
14     }
15 
16     public void setRadius(double radius) {
17         this.radius = radius;
18     }
19 
20     public double getPeri() {
21         return peri;
22     }
23 
24     public void setPeri(double peri) {
25         this.peri = peri;
26     }
27 
28     public double getArea() {
29         return area;
30     }
31 
32     public void setArea(double area) {
33         this.area = area;
34     }
35 
36     public Circle(double radius) {
37         this.radius = radius;
38     }
39 
40     @Override
41     public String toString() {
42         return "Circle{" +
43                 "radius=" + radius +
44                 ", peri=" + peri +
45                 ", area=" + area +
46                 '}';
47     }
48 
49     public static void main(String[] args){
50         ApplicationContext ac = new ClassPathXmlApplicationContext("classpath:spel.xml");
51         Circle circle = ac.getBean("circle",Circle.class);
52         System.out.println(circle);
53         Email email = ac.getBean("email",Email.class);
54         System.out.println(email);
55     }
56 }

 1 package spring;
 2 
 3 public class Email {
 4 
 5     private String email;
 6     private Circle circle;
 7 
 8     public Email(String email) {
 9         this.email = email;
10     }
11 
12     public Circle getCircle() {
13         return circle;
14     }
15 
16     public void setCircle(Circle circle) {
17         this.circle = circle;
18     }
19 
20     public String getEmail() {
21         return email;
22     }
23 
24     public void setEmail(String email) {
25         this.email = email;
26     }
27 
28     @Override
29     public String toString() {
30         return "Email{" +
31                 "email='" + email + '\'' +
32                 ", circle=" + circle +
33                 '}';
34     }
35 
36 }

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <beans xmlns="http://www.springframework.org/schema/beans"
 3        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4        xmlns:p="http://www.springframework.org/schema/p"
 5        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
 6 
 7 
 8     <!--
 9         SPRING EL Spring表达式语言
10         * 是一个支持运行时查询和操作对象图的强大表达式语言
11         * 使用#{...}作为定界符，在大括号内的就是SPEL
12         * SPEL为bean的动态赋值提供便利
13 
14         SP EL可以实现:
15             - 通过bean的id对bean进行引用
16             - 调用方法以及引用其他对象中的属性
17             - 计算表达式的值
18                 - 支持算术运算符 + - * / % ^
19                 - 支持+号连接字符串
20                 - 支持比较运算符 < > == <= >= lt gt eq le ge
21                 - 支持逻辑运算符 and or not |
22                 - 支持三目运算符  ?:
23             - 正则表达式的匹配
24             - 调用静态方法或者静态属性
25 
26      -->
27 
28     <bean id="circle" class="spring.Circle">
29         <constructor-arg name="radius" value="50"/>
30         <!--调用静态属性Math.PI-->
31         <!--引用其他对象中的属性circle.radius-->
32         <!--算术运算 * ^-->
33         <property name="peri" value="#{T(java.lang.Math).PI * circle.radius *2}"/>
34         <property name="area" value="#{T(java.lang.Math).PI * circle.radius^2}"/>
35     </bean>
36 
37 
38     <bean id="email" class="spring.Email">
39         <constructor-arg name="email" value="[email protected]"/>
40         <!--引用其他的bean-->
41         <property name="circle" value="#{circle}"/>
42         <!--正则表达式的匹配邮箱-->
43         <!--email最终的输出结果 email='true'-->
44         <property name="email" value="#{email.email matches '^[a-zA-Z0-9_.-]+@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*\.[a-zA-Z0-9]{2,6}$'}"/>
45     </bean>
46 
47 
48 
49 
50 </beans>