这篇文章主要讲解了在SpringBoot中怎么从application.yml中获取自定义常量,内容清晰明了,对此有兴趣的小伙伴可以学习一下,相信大家阅读完之后会有帮助。

要注意的地方是 application.yml 中不能用驼峰式写法(systemParams)要改成system-params

方法一:

引入依赖:

<!-- 支持 @ConfigurationProperties 注解 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-configuration-processor</artifactId> <optional>true</optional> </dependency>

配置文件(application.yml)中配置各个属性的值:

myProps: #自定义的属性和值 simpleProp: simplePropValue arrayProps: 1,2,3,4,5 listProp1: - name: abc value: abcValue - name: efg value: efgValue listProp2: - config2Value1 - config2Vavlue2 mapProps: key1: value1 key2: value2

创建一个bean来接收配置信息:

@Component @ConfigurationProperties(prefix="myProps") //接收application.yml中的myProps下面的属性 public class MyProps { private String simpleProp; private String[] arrayProps; private List<Map<String, String>> listProp1 = new ArrayList<>(); //接收prop1里面的属性值 private List<String> listProp2 = new ArrayList<>(); //接收prop2里面的属性值 private Map<String, String> mapProps = new HashMap<>(); //接收prop1里面的属性值 public String getSimpleProp() { return simpleProp; } //String类型的一定需要setter来接收属性值;maps, collections, 和 arrays 不需要 public void setSimpleProp(String simpleProp) { this.simpleProp = simpleProp; } public List<Map<String, String>> getListProp1() { return listProp1; } public List<String> getListProp2() { return listProp2; } public String[] getArrayProps() { return arrayProps; } public void setArrayProps(String[] arrayProps) { this.arrayProps = arrayProps; } public Map<String, String> getMapProps() { return mapProps; } public void setMapProps(Map<String, String> mapProps) { this.mapProps = mapProps; } }

启动后,这个bean里面的属性就会自动接收配置的值了。

单元测试用例:

@Autowired private MyProps myProps; @Test public void propsTest() throws JsonProcessingException { System.out.println("simpleProp: " + myProps.getSimpleProp()); System.out.println("arrayProps: " + objectMapper.writeValueAsString(myProps.getArrayProps())); System.out.println("listProp1: " + objectMapper.writeValueAsString(myProps.getListProp1())); System.out.println("listProp2: " + objectMapper.writeValueAsString(myProps.getListProp2())); System.out.println("mapProps: " + objectMapper.writeValueAsString(myProps.getMapProps())); }

测试结果:

simpleProp: simplePropValue arrayProps: ["1","2","3","4","5"] listProp1: [{"name":"abc","value":"abcValue"},{"name":"efg","value":"efgValue"}] listProp2: ["config2Value1","config2Vavlue2"] mapProps: {"key1":"value1","key2":"value2"}

方法二:

不用写 set 方法,直接给注解。

前提是要装一个插件:lombok 。 直接在插件中搜索到它,装上就行了

直接获取一个属性

image: location: D:/images/ /** * 在配置文件中配置的文件保存路径 */ @Value("${image.location}") private String location;

看完上述内容,是不是对在SpringBoot中怎么从application.yml中获取自定义常量有进一步的了解,如果还想学习更多内容,欢迎关注亿速云行业资讯频道。