spring- 注解---values

      spring- 注解---values

 

package com.zwj.bean;

import org.springframework.beans.factory.annotation.Value;

public class Person {
    
    //使用@Value赋值；
    //1、基本数值
    //2、可以写SpEL； #{}
    //3、可以写${}；取出配置文件【properties】中的值（在运行环境变量里面的值）
    
    @Value("张三")
    private String name;
    @Value("#{20-2}")
    private Integer age;
    
    @Value("${person.nickName}")
    private String nickName;
    
    
    
    public String getNickName() {
        return nickName;
    }
    public void setNickName(String nickName) {
        this.nickName = nickName;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
    
    public Person(String name, Integer age) {
        super();
        this.name = name;
        this.age = age;
    }
    public Person() {
        super();
        // TODO Auto-generated constructor stub
    }
    @Override
    public String toString() {
        return "Person [name=" + name + ", age=" + age + ", nickName=" + nickName + "]";
    }

    
    
    
    
    
    

}

Person

package com.zwj.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;

import com.zwj.bean.Person;

//使用@PropertySource读取外部配置文件中的k/v保存到运行的环境变量中;加载完外部的配置文件以后使用${}取出配置文件的值
@PropertySource(value={"classpath:/person.properties"})
@Configuration
public class MainConfigOfPropertyValues {
    
    @Bean
    public Person person(){
        return new Person();
    }

}

MainConfigOfPropertyValues

person.nickName=\u5C0F\u674E\u56DB

person.properties

package com.zwj.test;

import org.junit.Test;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.core.env.ConfigurableEnvironment;

import com.zwj.bean.Person;
import com.zwj.config.MainConfigOfPropertyValues;

public class IOCTest_PropertyValue {
    AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext(MainConfigOfPropertyValues.class);
    @Test
    public void test01(){
        printBeans(applicationContext);
        System.out.println("=============");
        
        Person person = (Person) applicationContext.getBean("person");
        System.out.println(person);
        
        
        ConfigurableEnvironment environment = applicationContext.getEnvironment();
        String property = environment.getProperty("person.nickName");
        System.out.println(property);
        applicationContext.close();
    }
/*
person
Person [name=张三, age=18, nickName=小李四]
小李四    
 */
    private void printBeans(AnnotationConfigApplicationContext applicationContext){
        String[] definitionNames = applicationContext.getBeanDefinitionNames();
        for (String name : definitionNames) {
            System.out.println(name);
        }
    }

}

IOCTest_PropertyValue

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.zwj</groupId>
  <artifactId>spring-annotation---values</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  
  <dependencies>
        <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.12.RELEASE</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/junit/junit -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>

    </dependencies>
</project>

pom.xml