spring boot yml properties example

1. Overview

This article is about spring boot yml properties example, we can manage spring boot configuration inapplication.properties or application.yml or application.yaml file.

• application.properties or .yml file should be available inside /resources folder at root location. Here is a way to change the location of application.properties or .yml file.
• Here is a priority to consider by spring boot if all three file available in /resources folder.
  • application.properties (1st property)
  • application.yml (2nd priority)
  • application.yaml (3rd priority)
• Here are some advantages to use application.yml instead of application.properties file
  • Easy to read properties
  • Convenient syntax to hierarchical format
  • Let’s check here application.properties and application.yml so we can differentiate between reading and convinces:

application.properties

spring.application.name=spring boot yml example
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost/test
server.port=9000

application.yml

spring:
   application:
     name: spring boot yml example
   datasource:
     driverClassName: com.mysql.jdbc.Driver
     url: jdbc:mysql://localhost/test
server:
   port: 9000

We have developed example maven, here is spring boot Gradle example using application.properties file, We can simply replace application.yml.

2. Example

spring boot yml properties example

2.1 pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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>spring-boot-example</groupId>
    <artifactId>spring-boot-yml-example</artifactId>
    <version>1.0-SNAPSHOT</version>
    <description>spring boot yml properties example</description>
    <packaging>jar</packaging>
    <!-- Inherit defaults from Spring Boot -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.4.RELEASE</version>
    </parent>
    <properties>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>
    <!-- Package as an executable jar -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

2.2 application.yml

server:
  port: 8989
  context-path: /demo
spring:
  application:
    name: spring yaml example

2.3 SpringBootConfig

package com.javadeveloperzone;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
/**
 * Created by JavaDeveloperZone on 06-05-2018.
 */
@SpringBootApplication
@ComponentScan // Using a root package also allows the @ComponentScan annotation to be used without needing to specify a basePackage attribute
public class SpringBootConfig {
    public static void main(String[] args) throws Exception {
        SpringApplication.run(SpringBootConfig.class, args);            // it wil start application
    }
}

2.4 HelloController

package com.javadeveloperzone.controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
 * Created by JavaDeveloperZone on 06-05-2018.
 */
@RestController
public class HelloController {
    @RequestMapping(value = "/hello")
    public String hello() {
        return "Spring boot YML Example";
    }
}

2.5 Output

Let’s run maven project : mvn spring-boot:run

 .   ____          _            __ _ _
/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
 ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/  ___)| |_)| | | | | || (_| |  ) ) ) )
 '  |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot ::        (v1.5.4.RELEASE)
2018-05-06 17:39:29.010  INFO 68888 --- [main] com.javadeveloperzone.SpringBootConfig   : Started SpringBootConfig in 6.506 seconds (JVM running for 42.699)

http://localhost:8989/demo/hello

spring boot yml properties example – output

3. References

• Spring boot YML documentation

4. Source Code

spring-boot-yaml-properties-example (173 KB)