这一章节我们来讨论一下SpEl表达式的简单介绍与嵌入值。
1.SpEl表达式简单介绍
Spring Excpression Language (SpEL)语言支持在执行时操作和查询对象
事实上就是在执行的过程中操作对应的对象或者值。
2.SpEl嵌入值
(1)domain
蛋糕类:(不变)
package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_14;
public class Cake {
private int id = 0;
private String name = "";
private double size = 0;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getSize() {
return size;
}
public void setSize(double size) {
this.size = size;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Override
public String toString() {
return "cake id:" + id + " name:" + name + " size:" + size;
}
}
(2)測试类:(打印蛋糕对象的属性)
package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_14;
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_14/ApplicationContext-test.xml" })
public class CakeTest {
@Autowired
private ApplicationContext applicationContext;
@Test
public void testCake() {
Cake cake = applicationContext.getBean(Cake.class);
System.out.println(cake);
}
}
(3)配置文件
通过#{}把实际的值嵌入到对应的属性里面。当然事实上是嵌入值是没什么意思,由于这样已经把程序给写死了。
測试输出:
cake id:1 name:blueberry cheese cake size:5.5
总结:这一章节主要介绍SpEl表达式的简单介绍与嵌入值。
文件夹:http://blog.csdn.net/raylee2007/article/details/50611627
我的github:https://github.com/raylee2015/my_new_spring