系列文章
1、SpringBoot(1)——创建SpringBoot项目的方式_基于注解方式开发aspectj springboot下载-CSDN博客
2、SpringBoot(2)——SpringBoot入门:微服务-CSDN博客
3、SpringBoot(3)——SpringBoot入门程序及解析-CSDN博客
4、SpringBoot(4)——SpringBoot自动配置原理-CSDN博客
文章目录
@Value获取值和@ConfigurationProperties获取值比较
1、配置文件
SpringBoot使用一个全局的配置文件,配置文件名是固定的;
•application.properties
•application.yml
其中:application.properties的优先级高于application.yml
配置文件的作用:
修改SpringBoot自动配置的默认值;SpringBoot在底层都给我们自动配置好;
YAML(YAML Ain't Markup Language)
YAMLisn't Markup Language:不是一个标记语言;
标记语言:
以前的配置文件;大多都使用的是xxxx.xml文件;
YAML:以数据为中心,比json、xml等更适合做配置文件;
大致样子如下:
2、YAML语法
1.基本语法
k: v (注意有空格)
表示一对键值对(空格必须有)
以空格的缩进来控制层级关系;只要是左对齐的一列数据,都是同一个层级的

2.值的写法
k: v字面直接来写
name: "zhangsan \n lisi"输出—— zhangsanlisi

name: ‘zhangsan \n lisi’:输出—— zhangsan \n lisi

3.对象、Map(属性和值)(键值对)

4.数组(List、Set)


3、配置文件值注入
方式一:@ConfigurationProperties
我们先创建一个Person的实体类(这个类很复杂,为了体现不同参数的传参形式)
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Component;
import org.springframework.validation.annotation.Validated;
import javax.validation.constraints.Email;
import java.util.Date;
import java.util.List;
import java.util.Map;
@Component
//@Validated
@ConfigurationProperties(prefix = "person")
public class Person {
//@Email
String email;
String hello;
String lastName;
int age;
boolean Boss;
@DateTimeFormat(pattern = "yyyy/MM/dd")
Date birth;
Map<String,String> maps;
List<String> list;
Dog dog;
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getHello() {
return hello;
}
public void setHello(String hello) {
this.hello = hello;
}
public Dog getDog() {
return dog;
}
public void setDog(Dog dog) {
this.dog = dog;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isBoss() {
return Boss;
}
public void setBoss(boolean boss) {
Boss = boss;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
public Map<String, String> getMaps() {
return maps;
}
public void setMaps(Map<String, String> maps) {
this.maps = maps;
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
@Override
public String toString() {
return "Person{" +
"email='" + email + '\'' +
", hello='" + hello + '\'' +
", lastName='" + lastName + '\'' +
", age=" + age +
", Boss=" + Boss +
", birth=" + birth +
", maps=" + maps +
", list=" + list +
", dog=" + dog +
'}';
}
}
参数类Dog
package cn.tx.springboot.model;
public class Dog {
private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Dog{" +
"name='" + name + '\'' +
", age=" + age +
'}';
}
}
配置文件application.yml
person:
email: 22444@aa.com
lastName: 亮
age: 18
Boss: true
birth: 2018/10/14
maps: {key1: 02, key2: 01}
list: [kily,lucy,house]
dog:
name: ${person.hello}_dog
age: ${random.int}
hello: luky
编写pom文件(我们可以导入配置文件处理器,以后编写配置就有提示了)
<!--导入配置文件处理器,配置文件进行绑定就会有提示-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
编写测试方法
@Controller
public class HelloController {
@Autowired
private Person person;
@ResponseBody /*返回字符串*/
@RequestMapping("/hello")
public String hello(){
System.out.println("Email: " + person.getEmail());
System.out.println("Hello: " + person.getHello());
System.out.println("LastName: " + person.getLastName());
System.out.println("Age: " + person.getAge());
System.out.println("Is Boss: " + person.isBoss());
System.out.println("Birth: " + person.getBirth());
System.out.println("Maps: ");
Map<String, String> maps = person.getMaps();
if (maps != null) {
maps.forEach((key, value) -> System.out.println(key + ": " + value));
}
System.out.println("List: ");
List<String> list = person.getList();
if (list != null) {
list.forEach(System.out::println);
}
System.out.println("Dog - Name: " + (person.getDog() != null ? person.getDog().getName() : "null"));
System.out.println("Dog - Age: " + (person.getDog() != null ? person.getDog().getAge() : "null"));
return "Hello World!";
}
}
测试结果如下图:
方式二:@Value
编写Person1实体类
package com.qcby.entity;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Component;
import org.springframework.validation.annotation.Validated;
import javax.validation.constraints.Email;
import java.util.Date;
import java.util.List;
import java.util.Map;
@Component
@Validated
//@ConfigurationProperties(prefix = "person")
public class Person1 {
@Email
@Value("${person.email}")
String email;
@Value("${person.hello}")
String hello;
@Value("${person.last-name}")
String lastName;
@Value("${person.age}")
int age;
@Value("${person.boss}")
boolean Boss;
@DateTimeFormat(pattern = "yyyy/MM/dd")
@Value("${person.birth}")
Date birth;
Map<String,String> maps;
@Value("${person.list}")
List<String> list;
Dog dog;
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getHello() {
return hello;
}
public void setHello(String hello) {
this.hello = hello;
}
public Dog getDog() {
return dog;
}
public void setDog(Dog dog) {
this.dog = dog;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isBoss() {
return Boss;
}
public void setBoss(boolean boss) {
Boss = boss;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
public Map<String, String> getMaps() {
return maps;
}
public void setMaps(Map<String, String> maps) {
this.maps = maps;
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
@Override
public String toString() {
return "Person1{" +
"email='" + email + '\'' +
", hello='" + hello + '\'' +
", lastName='" + lastName + '\'' +
", age=" + age +
", Boss=" + Boss +
", birth=" + birth +
", maps=" + maps +
", list=" + list +
", dog=" + dog +
'}';
}
}
配置application.properties文件
person.hello=luky
person.email=10199@tt.226m
person.last-name=亮
person.birth=2017/02/4
person.age=19
person.boss=true
person.list=dog,cat,animal
person.maps.key1=kkygjz
person.maps.key2=hhygyz
person.dog.name=${person.hello}_dog
person.dog.age=${person.age}
pom文档添加依赖(我加了@Email规范注解)
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>
编写测试类
(map和dog实现不出来,需要再添加逻辑,我这里没写)
@ResponseBody /*返回字符串*/
@RequestMapping("/hello1")
public String hello1(){
System.out.println("Email: " + person1.getEmail());
System.out.println("Hello: " + person1.getHello());
System.out.println("LastName: " + person1.getLastName());
System.out.println("Age: " + person1.getAge());
System.out.println("Is Boss: " + person1.isBoss());
System.out.println("Birth: " + person1.getBirth());
System.out.println("Maps: ");
Map<String, String> maps = person1.getMaps();
if (maps != null) {
maps.forEach((key, value) -> System.out.println(key + ": " + value));
}
System.out.println("List: ");
List<String> list = person1.getList();
if (list != null) {
list.forEach(System.out::println);
}
System.out.println("Dog - Name: " + (person1.getDog() != null ? person1.getDog().getName() : "null"));
System.out.println("Dog - Age: " + (person1.getDog() != null ? person1.getDog().getAge() : "null"));
return "Hello World!";
}
测试结果如下:
properties配置文件在idea中默认utf-8可能会乱码
@Value获取值和@ConfigurationProperties获取值比较

- 如果说,我们只是在某个业务逻辑中需要获取一下配置文件中的某项值,使用@Value;
- 如果说,我们专门编写了一个javaBean来和配置文件进行映射,我们就直接使用@ConfigurationProperties;
方式三:@PropertySource
@PropertySource 注解可以帮助我们将指定的属性文件加载到 Spring 的 Environment 中,这样就可以在应用中方便地使用这些属性。也就是说,创建这个类时,会去找@PropertySource注解中classpath中的配置文件。注意!不支持 YAML 文件
Person2实体类
package com.qcby.entity;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.PropertySource;
import org.springframework.format.annotation.DateTimeFormat;
import org.springframework.stereotype.Component;
import java.util.Date;
import java.util.List;
import java.util.Map;
@PropertySource(value = {"classpath:person.properties"})
@Component
@ConfigurationProperties(prefix = "person2")
public class Person2 {
String email;
String hello;
String lastName;
int age;
boolean Boss;
@DateTimeFormat(pattern = "yyyy/MM/dd")
Date birth;
Map<String,String> maps;
List<String> list;
Dog dog;
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getHello() {
return hello;
}
public void setHello(String hello) {
this.hello = hello;
}
public Dog getDog() {
return dog;
}
public void setDog(Dog dog) {
this.dog = dog;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isBoss() {
return Boss;
}
public void setBoss(boolean boss) {
Boss = boss;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
public Map<String, String> getMaps() {
return maps;
}
public void setMaps(Map<String, String> maps) {
this.maps = maps;
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
@Override
public String toString() {
return "Person2{" +
"email='" + email + '\'' +
", hello='" + hello + '\'' +
", lastName='" + lastName + '\'' +
", age=" + age +
", Boss=" + Boss +
", birth=" + birth +
", maps=" + maps +
", list=" + list +
", dog=" + dog +
'}';
}
}
person.properties
server.port=8085
person2.hello=luky
person2.email=10199@tt.226m
person2.last-name=亮
person2.birth=2017/02/4
person2.age=19
person2.boss=true
person2.list=dog,cat,animal
person2.maps.key1=kkygjz
person2.maps.key2=hhygyz
方式四:@ImportResource
导入Spring的配置文件,让配置文件里面的内容生效;Spring Boot里面没有Spring的配置文件,我们自己编写的配置文件,也不能自动识别;
想让Spring的配置文件生效,加载进来,需要把@ImportResource标注在一个配置类上
Person3实体类编写
package com.qcby.entity;
import org.springframework.context.annotation.ImportResource;
import org.springframework.format.annotation.DateTimeFormat;
import java.util.Date;
import java.util.List;
import java.util.Map;
@ImportResource(locations = "classpath:beans.xml")
public class Person3 {
String email;
String hello;
String lastName;
int age;
boolean Boss;
@DateTimeFormat(pattern = "yyyy/MM/dd")
Date birth;
Map<String,String> maps;
List<String> list;
Dog dog;
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getHello() {
return hello;
}
public void setHello(String hello) {
this.hello = hello;
}
public Dog getDog() {
return dog;
}
public void setDog(Dog dog) {
this.dog = dog;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isBoss() {
return Boss;
}
public void setBoss(boolean boss) {
Boss = boss;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
public Map<String, String> getMaps() {
return maps;
}
public void setMaps(Map<String, String> maps) {
this.maps = maps;
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
@Override
public String toString() {
return "Person3{" +
"email='" + email + '\'' +
", hello='" + hello + '\'' +
", lastName='" + lastName + '\'' +
", age=" + age +
", Boss=" + Boss +
", birth=" + birth +
", maps=" + maps +
", list=" + list +
", dog=" + dog +
'}';
}
}
beans.xml配置文件编写
<?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">
<!--将proson3交给ioc的配置文件-->
<bean id="person3" class="com.qcby.entity.Person3">
<property name="email" value="256984@qq.com"/>
<property name="age" value="19"/>
<property name="birth" value="2017/02/01"/>
<property name="boss" value="true"/>
</bean>
</beans>
在主启动类上添加注解
package com.qcby;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ImportResource;
/**
* @SpringBootApplication 来标注一个主程序类,说明这是一个Spring Boot应用
*/
/*springboot的@ComponentScan注解,扫描主启动类所在包及其所有子包*/
@ImportResource(locations = "classpath:beans.xml")
@SpringBootApplication
public class HelloWorldMainApplication {
public static void main(String[] args) {
// Spring应用启动起来
SpringApplication.run(HelloWorldMainApplication.class,args);
}}
编写测试类
package com.qcby;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.context.ApplicationContext;
@SpringBootTest
public class TxDemo4ApplicationTests {
@Autowired
ApplicationContext applicationContext;
@Test
public void contextLoads() {
Object bean = applicationContext.getBean("person3");
System.out.println(bean);
}
}
结果如下:
SpringBoot推荐给容器中添加组件的方式
推荐使用全注解的方式
1、配置类@Configuration------>Spring配置文件
2、使用@Bean给容器中添加组件
写一个HelloService类
package com.qcby.controller;
public class HelloService {
// 定义一个方法,用于返回问候语
public String sayHello() {
return "Hello, World!";
}
}
编写配置文件类
/**
* @Configuration:指明当前类是一个配置类;就是来替代之前的Spring配置文件
*
* 在配置文件中用<bean><bean/>标签添加组件
*
*/
@Configuration
public class MyAppConfig {
//将方法的返回值添加到容器中;容器中这个组件默认的id就是方法名
@Bean
public HelloService helloService02(){
System.out.println("配置类@Bean给容器中添加组件了...");
return new HelloService();
}
}
测试方法编写
@Autowired
ApplicationContext applicationContext;
@Test
public void contextLoads() {
HelloService helloService = applicationContext.getBean("helloService1", HelloService.class);
System.out.println(bean);
}
测试结果如下,可以看到该组件已经被添加:
4、Profile
1、多Profile文件

2、yml支持多文档块方式

3、激活指定profile
- 在配置文件中指定 spring.profiles.active=dev
- 命令行:
- java -jar spring-boot-02-config-0.0.1-SNAPSHOT.jar--spring.profiles.active=dev;
- 可以直接在测试的时候,配置传入命令行参数
- 虚拟机参数;
- -Dspring.profiles.active=dev
4、配置文件加载位置
springboot 启动会扫描以下位置的application.properties或者application.yml文件作为Spring boot的默认配置文件
配置文件可以存在于以下四个位置:
–file:./config/
–file:./
–classpath:/config/
–classpath:/
优先级由高到底,高优先级的配置会覆盖低优先级的配置;
SpringBoot会从这四个位置全部加载主配置文件;互补配置;
在-classpath:/的application.properties.中加入
server.servlet.context-path=/boot3访问根目录