Spring Boot学习，配置文件占位符和多环境支持
配置文件占位符和多环境支持
- 配置文件占位符
- RandomValuePropertySource
- 属性配置占位符
- 多环境支持（profile）
- profile文件的写法
- 激活指定profile
配置文件占位符
RandomValuePropertySource
配置文件可以使用Spring Boot 提供的一些随机数，如：
${random.value}, ${random.int}, ${random.long}, ${random.int(10)}, ${random.int(1024,1256)}
属性配置占位符
可以在配置文件中引用前面配置过的属性，如果引用的属性没有，还可以设置默认值，如果没有写默认值又没有定义，那么就会将表达式当成字符串输出。如：
app.name=MyApp
app.description=${app.name} is a Spring Boot Application.
app.desc=${app.version:v1.0} is current version
实体：
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;
import java.util.Date;
/**
* @ClassName Person
* @Date 2019/7/11 16:57
* @Description
*/
@Component
@ConfigurationProperties(prefix = "person")
public class Person {
private String surname;
private String name;
private Integer age;
private Date birth;
private boolean boss;
private String say;
public String getSurname() {
return surname;
}
public void setSurname(String surname) {
this.surname = surname;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
public boolean isBoss() {
return boss;
}
public void setBoss(boolean boss) {
this.boss = boss;
}
public String getSay() {
return say;
}
public void setSay(String say) {
this.say = say;
}
@Override
public String toString() {
return "Person{" +
"surname='" + surname + '\'' +
", name='" + name + '\'' +
", age=" + age +
", birth=" + birth +
", boss=" + boss +
", say='" + say + '\'' +
'}';
}
public void sayHi() {
System.out.println(say);
}
}
yml配置文件：
person:
surname: 张
name: 三${random.uuid} # 使用随机的UUID
age: ${random.int} # 随机的int
boss: false
birth: 2019/7/12
# 获取之前配置的surname、name、pet.type和pet.name属性，pet.type：没有配置，设置了默认值，pet.name：没有设置默认值
say: ${person.surname}先生名叫${person.name}，有一个宠物是${pet.type:狗}，叫做${pet.name}.
测试：
@Autowired
Person person;
@Test
public void contextLoads() {
System.out.println(person);
person.sayHi();
}
结果
Person{surname='张', name='三679487a1-30c7-4958-9b9e-ae52751be909', age=1640749302, birth=Fri Jul 12 00:00:00 CST 2019, boss=false, say='张先生名叫三a8a96ed5-409b-40cf-9aad-13322b36192b，有一个宠物是狗，叫做${pet.name}.'}
张先生名叫三a8a96ed5-409b-40cf-9aad-13322b36192b，有一个宠物是狗，叫做${pet.name}.
多环境支持（profile）
profile是Spring对不同环境提供不同配置功能的支持，可以通过激活、知道参数等方法快速切换环境。
profile文件的写法
-
多profile文件
文件名：application-{profile}.properties/yml，如application-dev.properties。默认使用的是application.properties -
yml多文档块
yml 有一种叫文档块，用’—'分割，如
server:
port: 8081
spring:
profiles:
active: prod
---
server:
port: 8082
spring:
profiles: dev
---
server:
port: 8083
spring:
profiles: prod
激活指定profile
- 在默认配置文件(application.properties)中指定，如：
# properties
spring.profiles.active=dev
# yml
spring:
profiles:
active: dev
- 命令行的方式
--spring.profiles.active=dev
// cmd 命令行
E:\jl_whw\private\git_repository\springboot\springbootconfigpropertysource\target>java -jar spring-boot-config-property-source-0.0.1-SNAPSHOT.jar --spring.profiles.active=prod
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.1.6.RELEASE)
2019-07-12 15:42:22.731 INFO 2840 --- [ main] pringBootConfigPropertySourceApplication : Starting SpringBootConfigPropertySourceApplication v0.0.1-SNAPSHOT on DESKTOP-O1S9VQ2 with PID 2840 (E:\jl_whw\private\git_repository\springboot\springbootconfigpropertysource\target\spring-boot-config-property-source-0.0.1-SNAPSHOT.jar started by JL_Computer in E:\jl_whw\private\git_repository\springboot\springbootconfigpropertysource\target)
2019-07-12 15:42:22.735 INFO 2840 --- [ main] pringBootConfigPropertySourceApplication : The following profiles are active: prod
2019-07-12 15:42:24.379 INFO 2840 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8083 (http)
2019-07-12 15:42:24.415 INFO 2840 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2019-07-12 15:42:24.415 INFO 2840 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.21]
2019-07-12 15:42:24.555 INFO 2840 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2019-07-12 15:42:24.555 INFO 2840 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1741 ms
组件添加成功！！！
2019-07-12 15:42:24.815 INFO 2840 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2019-07-12 15:42:25.055 INFO 2840 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8083 (http) with context path ''
2019-07-12 15:42:25.060 INFO 2840 --- [ main] pringBootConfigPropertySourceApplication : Started SpringBootConfigPropertySourceApplication in 2.887 seconds (JVM running for 3.505)
- 虚拟机参数
-Dspring.profiles.active=dev
用IDEA测试控制台和虚拟机参数：
