Spring实战——Bean定义中的SpEL表达式语言支持

分手后的思念是犯贱 2021-07-24 16:20 381阅读 0赞

**一 配置**

<?xml version="1.0" encoding="GBK"?>
    
    <beans xmlns="http://www.springframework.org/schema/beans"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns:p="http://www.springframework.org/schema/p"
         xmlns:util="http://www.springframework.org/schema/util"
         xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
         http://www.springframework.org/schema/util
         http://www.springframework.org/schema/util/spring-util-4.0.xsd">
         
         <util:properties id="confTest"
               location="classpath:test_zh_CN.properties"/>
         
         <bean id="author"  class="org.crazyit.app.service.impl.Author"
               p:name="#{T(java.lang.Math).random()}"
               p:axe="#{new  org.crazyit.app.service.impl.SteelAxe()}"
               p:books="#{ {confTest.a , confTest.b} }"/>
    </beans>

**二 资源文件**

a=\u300a\u8f7b\u91cf\u7ea7Java  EE\u4f01\u4e1a\u5e94\u7528\u5b9e\u6218\u300b
    b=\u300a\u75af\u72c2Java\u8bb2\u4e49\u300b

**三 接口**

Axe

package org.crazyit.app.service;
    
    public interface Axe
    {
         String chop();
    }

Person

package org.crazyit.app.service;
    import java.util.*;
    
    public interface Person
    {
         public void useAxe();
         public List<String> getBooks();
         public String getName();
    }

**四 Bean**

Author

package org.crazyit.app.service.impl;
    
    
    import java.util.*;
    import org.crazyit.app.service.*;
    
    public class Author implements Person
    {
        private Integer id;
        private String name;
        private List<String> books;
        private Axe axe;
        // id的setter和getter方法
        public void setId(Integer id)
        {
            this.id = id;
        }
        public Integer getId()
        {
            return this.id;
        }
    
    
        // name的setter和getter方法
        public void setName(String name)
        {
            this.name = name;
        }
        public String getName()
        {
            return this.name;
        }
    
    
        // books的setter和getter方法
        public void setBooks(List<String> books)
        {
            this.books = books;
        }
        public List<String> getBooks()
        {
            return this.books;
        }
    
    
        // axe的setter方法
        public void setAxe(Axe axe)
        {
            this.axe = axe;
        }
    
    
        public void useAxe()
        {
            System.out.println("我是"
                + name + "，正在砍柴\n" + axe.chop());
        }
    }

SteelAxe

package org.crazyit.app.service.impl;
    import org.crazyit.app.service.*;
    
    public class SteelAxe implements Axe
    {
         public String chop()
         {
               return "钢斧砍柴很快！";
         }
    }

**五 测试类**

package lee;
    
    
    import org.springframework.context.*;
    import org.springframework.context.support.*;
    
    
    import java.util.*;
    
    
    import org.crazyit.app.service.*;
    
    public class SpELTest
    {
        public static void main(String[] args)
        {
            ApplicationContext ctx = new
                ClassPathXmlApplicationContext("beans.xml");
            Person author = ctx.getBean("author" , Person.class);
            System.out.println(author.getBooks());
            author.useAxe();
    
    
        }
    }

**六 测试结果**

[《轻量级Java EE企业应用实战》, 《疯狂Java讲义》]
    我是0.06178107142599454，正在砍柴
    钢斧砍柴很快！