从头认识Spring-1.15 对SpEl的值的操作（2）-对比值

这一章节我们来讨论一下对SpEl的值的对比值。

1.domain

烤炉类：（增加了bigOrNot属性）

package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_18;public class Oven {private String name = "";private double size = 0;private boolean bigOrNot = false;public boolean isBigOrNot() {return bigOrNot;}public void setBigOrNot(boolean bigOrNot) {this.bigOrNot = bigOrNot;}public double getSize() {return size;}public void setSize(double size) {this.size = size;}@Overridepublic String toString() {return name + " size:" + size;}public String getName() {return name;}public void setName(String name) {this.name = name;}}

厨师类：（增加检查烤炉的方法）

package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_18;public class Chief {private String name = "";private Oven oven;public void checkOven() {if (getOven().isBigOrNot()) {System.out.println(getOven());System.out.println("oven is big");} else {System.out.println(getOven());System.out.println("oven is not big");}}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;}}

2.测试类：（把使用烤炉换成检查烤炉）

package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_18;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_18/ApplicationContext-test.xml" })public class ChiefTest {@Autowiredprivate ApplicationContext applicationContext;@Testpublic void testChief() {Chief jack = (Chief) applicationContext.getBean("jack");jack.checkOven();Chief mike = (Chief) applicationContext.getBean("mike");mike.checkOven();Chief rose = (Chief) applicationContext.getBean("rose");rose.checkOven();}}

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.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsdhttp://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsdhttp://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsdhttp://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.0.xsdhttp://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_18.Oven"p:name="smallOven" p:size="#{2*5}" p:bigOrNot="#{10 >= 8}" /><bean id="midOven"class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_18.Oven"p:name="midOven" p:size="#{T(java.lang.Math).PI*4}" p:bigOrNot="#{smallOven.getSize() lt 8}" /><bean id="bigOven"class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_18.Oven"p:name="bigOven" p:size="#{smallOven.getSize()*4}" p:bigOrNot="#{midOven.getSize() gt 8}" /><bean id="mike"class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_18.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_18.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_18.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p:bigOrNot属性，在这里我们可以通过对比符来对比两个数值，从而产生最后的结果。

测试输出：

midOven size:12.566370614359172
oven is not big
smallOven size:10.0
oven is big
bigOven size:40.0
oven is big

我们上面只是演示了一部分，它有：>大于 <小于 >=大于等于 <=小于等于 ==等于，大家后面可以逐一尝试。

总结：这一章节我们讨论了对SpEl的值的对比值。

目录：http://blog.csdn.net/raylee2007/article/details/50611627 

 

我的github：https://github.com/raylee2015/my_new_spring