Use of Spring Boot configuration files

Spring Boot configuration files have two writing formats, one ending with .properties and the other ending with .yaml.

.properties configuration file

When creating a new project, the file has been created for us, but it is an empty file
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We can open the file configuration and modify it as follows

generate a random character

#生成一个随机字符
mx.secret=${random.secret}

Get the value in the controller

@RestController
@RequestMapping("/index")
public class IndexController {

    @Value(value="${mx.secret}")
    private String secret;

    @RequestMapping
    public String index() {
        return "Hello World";
    }

    @RequestMapping("get")
    public Map<String, String> get(@RequestParam String name) {     
        Map map = new HashMap<>();
        map.put("name", name);
        map.put("address", "北京丰台");
        map.put("secret", secret);
        return map;
    }
}

Open the browser to visit the test address
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write a fixed reference

mx.name=www.example.mx
mx.description=${mx.name} is good

Get this property in the controller

@RestController
@RequestMapping("/index")
public class IndexController {

    @Value(value="${mx.secret}")
    private String secret;

    @Value(value="${mx.description}")
    private String description;

    @RequestMapping
    public String index() {
        return "Hello World";
    }

    @RequestMapping("get")
    public Map<String, String> get(@RequestParam String name) {

        Map map = new HashMap<>();
        map.put("name", name);
        map.put("address", "北京丰台");
        map.put("secret", secret);
        map.put("description", description);
        return map;
    }
}

Open the browser to visit the test address
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Modify port, time format, time zone

Since the default time zone of Spring Boot is set to Los Angeles, USA, it will cause our output time to be wrong

#端口设置
server.port=8090
#日期格式化
spring.jackson.date-format=yyyy-MM-dd HH-mm-ss
#时区
spring.jackson.time-zone=GMT+8

Get properties in controller

@RestController
@RequestMapping("/index")
public class IndexController {

    @Value(value="${mx.secret}")
    private String secret;

    @Value(value="${mx.description}")
    private String description;

    @RequestMapping
    public String index() {
        return "Hello World";
    }

    @RequestMapping("get")
    public Map<String, String> get(@RequestParam String name) {

        Map map = new HashMap<>();
        map.put("name", name);
        map.put("address", "北京丰台");
        map.put("secret", secret);
        map.put("description", description);
        return map;
    }

    @RequestMapping("find/{id}/{name}")
    public User find(@PathVariable String id, @PathVariable String name) {  
        User user = new User();
        user.setAge(99);
        user.setId(id);
        user.setName(name);
        user.setDate(new Date());
        return user;
    }
}

Open the browser to access the test address
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and you can see that the port has been modified successfully.

Spring Boot .properties use of multiple configuration files

Add two new configuration files, respectively application-dev.properties and application-test.properties
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are configured as follows

#生成一个随机字符
mx.secret=${random.secret}

mx.name=www.example.mx
mx.description=${mx.name} is good

#端口设置
server.port=8095

spring.jackson.date-format=yyyy-MM-dd HH-mm-ss
spring.jackson.time-zone=GMT+8

#生成一个随机字符
mx.secret=${random.secret}

mx.name=www.example.mx
mx.description=${mx.name} is good

#端口设置
server.port=8090

spring.jackson.date-format=yyyy-MM-dd HH-mm-ss
spring.jackson.time-zone=GMT+8

Then modify the application.properties configuration to add the following code

spring.profiles.active=test

Restart the project and find that the configuration in application-test.properties has been used. Similarly, if it is changed to dev, the configuration in application-dev.properties is used.

We can also run parameters in the command line
1. First package the project
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2. Right-click to open the command line and enter the command as follows

 java -jar .\spring-boot-0.0.1-SNAPSHOT.jar

3. The configuration of application-test.properties is running at this time
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4. We can also run the following command

java -jar .\spring-boot-0.0.1-SNAPSHOT.jar --spring.profiles.active=dev

5. The configuration of application-dev.properties is running at this time
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.yaml configuration file

You can create a new .yaml file yourself as follows
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The configuration format is as follows

#生成一个随机字符
mx: 
  secret: ${random.secret}
  name: www.example.mx
  description: ${mx.name} is good

#端口设置
server: 
  port: 8081

spring: 
  jackson: 
    date-format: yyyy-MM-dd HH-mm-ss
    time-zone: GMT+8

Open the browser to access the test address
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The effect is actually the same, .yaml makes the writing more concise

Spring Boot .yaml multi-configuration file usage

Modify the configuration file as follows, .yaml can use multiple configurations in one file, ---separated by:

#生成一个随机字符
mx: 
  secret: ${random.secret}
  name: www.example.mx
  description: ${mx.name} is good

#端口设置
server: 
  port: 8081

spring: 
  profiles:
    active: test
  jackson: 
    date-format: yyyy-MM-dd HH-mm-ss
    time-zone: GMT+8

---
spring:
  profiles: test

server:
  port: 8082

---
spring:
  profiles: dev

server:
  port: 8083

Looking at the command line, you can see the configuration that has been used for test
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