spring boot 读取配置文件（application.yml）中的属性值

在spring boot中，简单几步，读取配置文件（application.yml）中各种不同类型的属性值：

1、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>

2、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

3、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。

4、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"}

源代码参考：https://github.com/xujijun/my-spring-boot