spel ：spring表达式语言 简称（spel）是一个支持运行时查询和操作对象图的强大表达式语言
语法类似el ：spel使用 #{...}作为定界符,所有在大括号中的字符都将被认为是spel
spel 为bean的属性进行动态赋值提供了便利
通过spel可以实现
a.通过bean'的id对bean进行引用
b.调用方法以及引用对象中的属性
c.计算表达式的值
d.正则表达式的匹配
下面做个小测试
4. xml中的配置
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="applic" class="com.spring.entity.applic">
<property name="address" value="北京"></property>
<property name="age" value="14"></property>
<property name="name" value="王府"></property>
<property name="sex" value="F"></property>
</bean>
<bean id="spel" class="com.spring.entity.Spel">
<property name="price" value="#{33}"></property>
<!-- 使用spel引用其他的 bean -->
<property name="applic" value="#{applic}"></property>
<!-- 引用其他bean的属性 -->
<property name="name" value="#{applic.name}"></property>
<!-- 引用其他bean的方法 -->
<property name="addr" value="#{applic.te()}"></property>
</bean>
</beans>5.applic 实体
package com.spring.entity;
public class applic {
private String name;
private String address;
private Integer age;
private String sex;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
@Override
public String toString() {
return "applic [name=" + name + ", address=" + address + ", age=" + age + ", sex=" + sex + "]";
}
public applic(String name, String address, Integer age, String sex) {
super();
this.name = name;
this.address = address;
this.age = age;
this.sex = sex;
}
public applic() {
super();
}
public void te(){
System.out.println("我是applic的te()方法！！！");
}
}6.spel 实体
package com.spring.entity;
public class Spel {
private String name;
private String addr;
private String price;
private applic applic;
public applic getApplic() {
return applic;
}
public void setApplic(applic applic) {
this.applic = applic;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddr() {
return addr;
}
public void setAddr(String addr) {
this.addr = addr;
}
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
public Spel(String name, String addr, String price, com.spring.entity.applic applic) {
super();
this.name = name;
this.addr = addr;
this.price = price;
this.applic = applic;
}
public Spel() {
super();
}
@Override
public String toString() {
return "Spel [name=" + name + ", addr=" + addr + ", price=" + price + ", applic=" + applic + "]";
}
}7.测试
package com.spring.test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.spring.entity.Spel;
public class TestSpel {
public static void main(String[] args) {
ApplicationContext ctx = new ClassPathXmlApplicationContext("spel.xml");
Spel spel = (Spel)ctx.getBean("spel");
System.out.println(spel);
}
}测试结果：
我是applic的te()方法！！！
Spel [name=王府, addr=null, price=33, applic=applic [name=王府, address=北京, age=14, sex=F]]
