从头认识Spring-1.15 对SpEl的值的操作-数值运算
Posted 李灵晖
tags:
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这一章节我们来讨论一下对SpEl的值的运算。
1.domain
烤炉类:(不变)
package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17;
public class Oven {
private String name = "";
private double size = 0;
public double getSize() {
return size;
}
public void setSize(double size) {
this.size = size;
}
@Override
public String toString() {
return name + " size:" + size;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
厨师类:(为了方便,减少了friend的属性)
package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17;
public class Chief {
private String name = "";
private Oven oven;
public String getName() {
return name;
}
public Oven getOven() {
return oven;
}
public void setName(String name) {
this.name = name;
}
public void setOven(Oven oven) {
this.oven = oven;
}
public void userOven() {
System.out.println(name + " use " + oven);
}
}
2.测试类:(不变)
package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {
"/com/raylee/my_new_spring/my_new_spring/ch01/topic_1_17/ApplicationContext-test.xml" })
public class ChiefTest {
@Autowired
private ApplicationContext applicationContext;
@Test
public void testChief() {
Chief jack = (Chief) applicationContext.getBean("jack");
jack.userOven();
Chief mike = (Chief) applicationContext.getBean("mike");
mike.userOven();
Chief rose = (Chief) applicationContext.getBean("rose");
rose.userOven();
}
}
3.配置文件:(重点)
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsd
http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.0.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
<bean id="smallOven"
class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17.Oven"
p:name="smallOven" p:size="#{2*3}" />
<bean id="midOven"
class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17.Oven"
p:name="smallOven" p:size="#{T(java.lang.Math).PI*4}" />
<bean id="bigOven"
class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17.Oven"
p:name="smallOven" p:size="#{smallOven.getSize()*4}" />
<bean id="mike"
class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17.Chief"
p:name="mike">
<property name="oven" ref="smallOven" />
</bean>
<bean id="jack"
class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17.Chief"
p:name="jack">
<property name="oven" ref="midOven" />
</bean>
<bean id="rose"
class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_17.Chief"
p:name="rose">
<property name="oven" ref="bigOven" />
</bean>
</beans>
配置文件的重点就是看Oven里面的size属性,在这里我们可以通过运行符来计算我们需要的值,直接对SpEl的值进行操作。
测试输出:
jack use smallOven size:12.566370614359172
mike use smallOven size:6.0
rose use smallOven size:24.0
我们上面只是演示了乘法,它有:+ 加 - 减 * 乘 / 除 % 模 ^平方 这几种运算方式,大家后面可以逐一尝试。
总结:这一章节我们讨论了对SpEl的值的运算。
目录:http://blog.csdn.net/raylee2007/article/details/50611627
我的github:https://github.com/raylee2015/my_new_spring
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