Java如何使用Spring EL进行数学运算？
我们知道，在SpringEL中可以表示的最简单的值是文字值，例如number。此外，我们还可以使用SpringEL进行数学运算。下面的spring配置向您展示了如何使用SpringExpressionLanguage进行数学运算。这些操作包括：
加法运算（+）
减法运算(-)
乘法运算（*）
除法运算（/）
模运算（%）
幂运算（^）
<?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="myBean">
<property name="total" value="#{50 + 50}"/>
<property name="length" value="#{100 - 10}"/>
<property name="size" value="#{10 * 10}"/>
<property name="reminder" value="#{10 % 3}"/>
<property name="distance" value="#{1000 / 10}"/>
<property name="power" value="#{2 ^ 10}"/>
</bean>
</beans>上面的配置需要一个名为MyBean的bean/pojo。这是一个简单的类，其中包含一些字段以及getter和setter。随后是一个名为SpELMathOperationDemo的简单类，用于演示SpringEL数学运算。
package org.nhooo.example.spring.el;
public class MyBean {
private int total;
private int length;
private int size;
private float distance;
private int reminder;
private int power;
public int getTotal() {
return total;
}
public void setTotal(int total) {
this.total = total;
}
public int getLength() {
return length;
}
public void setLength(int length) {
this.length = length;
}
public int getSize() {
return size;
}
public void setSize(int size) {
this.size = size;
}
public float getDistance() {
return distance;
}
public void setDistance(float distance) {
this.distance = distance;
}
public int getReminder() {
return reminder;
}
public void setReminder(int reminder) {
this.reminder = reminder;
}
public int getPower() {
return power;
}
public void setPower(int power) {
this.power = power;
}
}package org.nhooo.example.spring.el;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class SpELMathOperationDemo {
public static void main(String[] args) {
ApplicationContext context =
new ClassPathXmlApplicationContext("spel-math-operation.xml");
MyBean bean = (MyBean) context.getBean("myBean");
System.out.println("bean.getTotal() = " + bean.getTotal());
System.out.println("bean.getLength() = " + bean.getLength());
System.out.println("bean.getSize() = " + bean.getSize());
System.out.println("bean.getReminder() = " + bean.getReminder());
System.out.println("bean.getDistance() = " + bean.getDistance());
System.out.println("bean.getPower() = " + bean.getPower());
}
}这是由代码片段打印出来的输出：
bean.getTotal() = 100 bean.getLength() = 90 bean.getSize() = 100 bean.getReminder() = 1 bean.getDistance() = 100.0 bean.getPower() = 1024