通过Bean的id对Bean进行引用  调用方法及引用对象的属性  计算表达式的值  正则表达式匹配

字面量的表示：

整型：#{5}  小数：#{3.45}  科学计数法：#[1e4]  字符串：可以使用单引号或双引号早味字符串的定界符：#{'tom'}，#{"tom"}  布尔值：#{false}

SpEL支持的运算符号：+ - * / % ^ < > == <= >= lt gt eq le ge and or not | (?:) if-else 正则表达式等等

调用静态属性和方法：通过T()

以下代码均忽略类中的getter、setter和to_string方法。

Car.java

package com.gong.spring.beans.spel;public class Car { public Car() { } public Car(String name) {  this.name = name; } private String name; //轮胎周长 private double tyrePerimeter; private double price;}

Address.java

package com.gong.spring.beans.spel;public class Address { private String city; private String street;}

Student.java

package com.gong.spring.beans.spel;public class Student {  private String name; private int age; private double score; private String city; private String info; private Car car; private Address address;}

beans-spel.xml

Main.java

package com.gong.spring.beans.spel;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Main { public static void main(String[] args) {  //1.创建spring的IOC容器对象  ApplicationContext ctx = new ClassPathXmlApplicationContext("beans-spel.xml");  //2.从容器中获取Bean实例  Student student = (Student) ctx.getBean("student");  System.out.println(student.toString()); }}