Spring Boot YAML示例

短命女 2023-02-15 05:12 17阅读 0赞

![yaml-vs-properties][]![yaml-vs-properties][]

在本文中，我们将向您展示如何在Spring Boot中使用[YAML][]代替属性文件。

经过测试：

*  Spring Boot 2.1.2发布
 *  Maven 3
 *  Snakeyaml：jar：1.23

简而言之，在`src/resources`文件夹中创建一个`application.yml` ，Spring Boot将自动加载并解析`.yml`文件，并将值绑定到用`@ConfigurationProperties`注释的类中。

*PS YAML文件无法通过使用@PropertySource加载*

## 1. YAML和属性 ##

application.yml

logging:
      level:
        org.springframework: ERROR
        com.mkyong: DEBUG
    
    spring:
      profiles:
        active: dev
      main:
        banner-mode: off
    
    email: yaml@mkyong.com
    thread-pool: 10
    
    wordpress:
      menus:
        - title: Home
          name: Home
          path: /
        - title: About
          name: About
          path: /about
      themes:
        default-folder: /wp-content/themes/mkyong
      servers:
        - ip: 127.0.0.1
          path: /dev1
        - ip: 127.0.0.2
          path: /dev2
        - ip: 127.0.0.3
          path: /dev3

application.properties

# Spring Boot
    logging.level.org.springframework=ERROR
    logging.level.com.mkyong=DEBUG
    spring.profiles.active=dev
    spring.main.banner-mode=off
    
    # Global
    email=properties@mkyong.com
    thread-pool=10
    
    # WordPress
    wordpress.menus[0].title=Home
    wordpress.menus[0].name=Home
    wordpress.menus[0].path=/
    wordpress.menus[1].title=About
    wordpress.menus[1].name=About
    wordpress.menus[1].path=/about
    wordpress.themes.default-folder=/wp-content/themes/mkyong
    wordpress.servers[0].ip=127.0.0.1
    wordpress.servers[0].path=/dev1
    wordpress.servers[1].ip=127.0.0.2
    wordpress.servers[1].path=/dev2
    wordpress.servers[2].ip=127.0.0.3
    wordpress.servers[2].path=/dev3

## 2.项目结构 ##

![项目目录][format_png]![项目目录][format_png]

## 3.项目依赖性 ##

Spring Boot使用[SnakeYAML][]库来解析YAML文件，而SnakeYAML库由`spring-boot-starter`

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>
    
        <artifactId>spring-boot-yaml-example</artifactId>
        <packaging>jar</packaging>
        <name>Spring Boot YAML Example</name>
        <url>https://www.mkyong.com</url>
        <version>1.0</version>
    
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.2.RELEASE</version>
        </parent>
    
        <properties>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter</artifactId>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
    
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <version>2.22.0</version>
                </plugin>
    
            </plugins>
        </build>
    </project>

项目依赖项：

+- org.springframework.boot:spring-boot-starter:jar:2.1.2.RELEASE:compile
    [INFO] |  +- org.springframework.boot:spring-boot:jar:2.1.2.RELEASE:compile
    [INFO] |  |  \- org.springframework:spring-context:jar:5.1.4.RELEASE:compile
    [INFO] |  |     +- org.springframework:spring-aop:jar:5.1.4.RELEASE:compile
    [INFO] |  |     +- org.springframework:spring-beans:jar:5.1.4.RELEASE:compile
    [INFO] |  |     \- org.springframework:spring-expression:jar:5.1.4.RELEASE:compile
    [INFO] |  +- org.springframework.boot:spring-boot-autoconfigure:jar:2.1.2.RELEASE:compile
    [INFO] |  +- org.springframework.boot:spring-boot-starter-logging:jar:2.1.2.RELEASE:compile
    [INFO] |  |  +- ch.qos.logback:logback-classic:jar:1.2.3:compile
    [INFO] |  |  |  \- ch.qos.logback:logback-core:jar:1.2.3:compile
    [INFO] |  |  +- org.apache.logging.log4j:log4j-to-slf4j:jar:2.11.1:compile
    [INFO] |  |  |  \- org.apache.logging.log4j:log4j-api:jar:2.11.1:compile
    [INFO] |  |  \- org.slf4j:jul-to-slf4j:jar:1.7.25:compile
    [INFO] |  +- javax.annotation:javax.annotation-api:jar:1.3.2:compile
    [INFO] |  +- org.springframework:spring-core:jar:5.1.4.RELEASE:compile
    [INFO] |  |  \- org.springframework:spring-jcl:jar:5.1.4.RELEASE:compile
    [INFO] |  \- org.yaml:snakeyaml:jar:1.23:runtime <<------------- SnakeYAML

## 4. Spring Boot + YAML ##

4.1 Spring Boot将加载并解析YAML文件，并绑定以下`@ConfigurationProperties`类中的值。

GlobalProperties.java

package com.mkyong.config;
    
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.stereotype.Component;
    
    @Component
    @ConfigurationProperties // no prefix, root level.
    public class GlobalProperties {
    
        //thread-pool , relax binding
        private int threadPool;
        private String email;
    
        //... getters and setters, toString()
    }

WordPressProperties.java

package com.mkyong.config;
    
    import com.mkyong.config.model.Menu;
    import com.mkyong.config.model.Server;
    import com.mkyong.config.model.Theme;
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.stereotype.Component;
    
    import java.util.ArrayList;
    import java.util.List;
    
    @Component
    @ConfigurationProperties("wordpress")
    public class WordPressProperties {
    
        private List<Menu> menus = new ArrayList<>();
        private Theme themes;
        private List<Server> servers = new ArrayList<>();
    
        //... getters and setters, toString()
    }

4.2模型，没什么特别的，只是一些标准的类。

Menu.java

package com.mkyong.config.model;
    
    public class Menu {
    
        private String name;
        private String path;
        private String title;
    
        //... getters and setters, toString()
    }

Server.java

package com.mkyong.config.model;
    
    public class Server {
    
        private String ip;
        private String path;
    
        //... getters and setters, toString()
    }

Theme.java

package com.mkyong.config.model;
    
    public class Theme {
    
        private String defaultFolder;
    
        //... getters and setters, toString()
    }

4.3正常启动Spring Boot并打印出值。

Application.java

package com.mkyong;
    
    import com.mkyong.config.GlobalProperties;
    import com.mkyong.config.WordpressProperties;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.CommandLineRunner;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    
    @SpringBootApplication
    public class Application implements CommandLineRunner {
    
        @Autowired
        private WordPressProperties wpProperties;
    
        @Autowired
        private GlobalProperties globalProperties;
    
        public static void main(String[] args) {
            SpringApplication.run(Application.class, args);
        }
    
        @Override
        public void run(String... args) {
            System.out.println(globalProperties);
            System.out.println(wpProperties);
        }
    }

## 5.演示 ##

打包并运行它。

# run spring boot directly
    $ mvn spring-boot:run
    
    # or package and run it 
    $ mvn package
    $ java -jar target/spring-boot-yaml-example-1.0.jar

输出量

GlobalProperties{
    	threadPool=10, 
    	email='properties@mkyong.com'
    }
    
    WordpressProperties{
    	menus=[
    		Menu{name='Home', path='/', title='Home'}, 
    		Menu{name='About', path='/about', title='About'}
    	], 
    	themes=Theme{defaultFolder='/wp-content/themes/mkyong'}, 
    	servers=[
    		Server{ip='127.0.0.1', path='/dev1'}, 
    		Server{ip='127.0.0.2', path='/dev2'}, 
    		Server{ip='127.0.0.3', path='/dev3'}
    	]
    }

> **YAML多配置文件**  
> 参考这个Spring Boot + Multiple Profiles YAML示例

## 下载源代码 ##

> $ git clone [https://github.com/mkyong/spring-boot.git][https_github.com_mkyong_spring-boot.git]  
> $ cd yaml-简单  
> $ mvn spring-boot：运行

## 参考文献 ##

*  [YAML][]
 *  [维基百科-YAML][-YAML]
 *  [蛇YAML][SnakeYAML]
 *  [使用YAML代替属性][YAML 1]
 *  Spring Boot @ConfigurationProperties示例

标签： [属性文件][Link 1] [spring boot][] [yaml][]

> 翻译自: [https://mkyong.com/spring-boot/spring-boot-yaml-example/][https_mkyong.com_spring-boot_spring-boot-yaml-example]

[yaml-vs-properties]: http://imgconvert.csdnimg.cn/aHR0cHM6Ly9ta3lvbmcuY29tL3dwLWNvbnRlbnQvdXBsb2Fkcy8yMDE5LzAzL3NwcmluZy1ib290LXlhbWwtZXhhbXBsZS5wbmc?x-oss-process=image/format,png
[YAML]: https://yaml.org/
[format_png]: http://imgconvert.csdnimg.cn/aHR0cHM6Ly9ta3lvbmcuY29tL3dwLWNvbnRlbnQvdXBsb2Fkcy8yMDE5LzAzL3NwcmluZy1ib290LXlhbWwtZXhhbXBsZS0xLnBuZw?x-oss-process=image/format,png
[SnakeYAML]: http://www.snakeyaml.org/
[https_github.com_mkyong_spring-boot.git]: https://github.com/mkyong/spring-boot.git
[-YAML]: https://en.wikipedia.org/wiki/YAML
[YAML 1]: https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-external-config.html#boot-features-external-config-yaml
[Link 1]: https://mkyong.com/tag/properties-file/
[spring boot]: https://mkyong.com/tag/spring-boot/
[yaml]: https://mkyong.com/tag/yaml/
[https_mkyong.com_spring-boot_spring-boot-yaml-example]: https://mkyong.com/spring-boot/spring-boot-yaml-example/