Summary of YAML configuration methods

Table of contents

1 Grammar

2 Configuration information

2.1 Literals (ordinary values: numbers, strings, Boolean)

2.2 Objects

2.3 Map

2.4 List

2.5 Array

3 Summary

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1 Grammar

• k: (space) v: represents a key-value pair (space must be present)
• Case Sensitive
• Use indentation to indicate hierarchical relationships
• Tabs are not allowed for indentation, only spaces are allowed.
• The number of spaces for indentation does not matter, as long as elements at the same level are left aligned
• # represents comments
• The string does not need to be quoted. If '' single quotes or "" double quotes are added, the content will be escaped [single quote escape] or not escaped [double quote not escaped]

2 Configuration information

2.1 Literals (ordinary values: numbers, strings, Boolean)

Written: k: v

Strings do not need to be enclosed in single quotes or double quotes by default;

"": double quotes; special characters in the string will not be escaped; special characters will be used as the meaning they want to express.

name: "zhangsan \n lisi": output; zhangsan newline lisi

'': single quote; will escape special characters, which are ultimately just ordinary string data.

name: 'zhangsan \n lisi': output; zhangsan \n lisi

server:
 port: 8080
 servlet:
    context-path: /

method of obtaining:

@Value("${server.port}")
private Integer port;

2.2 Objects

Writing method: k: v, write the relationship between the object's attributes and values ​​on the next line; pay attention to the indentation

example: 
  #对象行内写法
	school: '{"name": "北京市第一中学","location": "北京市"}'
	school2:
    name: 北京市第一中学
    location: 北京市

@Data
@Component
@ConfigurationProperties(prefix = "example")
public class TestConfig2 {
    
    private School school;

    private School school2;
    
}

2.3 Map

Writing method: k: v, write the relationship between the object's attributes and values ​​on the next line; pay attention to the indentation

• Inline writing and how to obtain it

map:
  example: '{"key1": "value1", "key2": "value2"}'

@Component
public class TestConfig {

    @Value("#{${map.example}}")
    private Map<String, String> map;

}

• Offline writing and how to obtain it

example:
  map:
    key1: value1
    key2: value2

@Data
@Component
@ConfigurationProperties(prefix = "example")
public class TestConfig2 {
    
    private Map<String, String> map;
    
}

2.4 List

• Outline writing method (use - value to represent an element in the array) and how to obtain it

example:
  list:
    - list1
    - list2
    - list3

@Data
@Component
@ConfigurationProperties(prefix = "example")
public class TestConfig2 {
    
    private List<String> list;
    
}

• Inline writing and how to obtain it

list:
  # 行内写法
  example: list1,list2,list3

@Component
public class TestConfig {

    // @Value("#{'${list.example2}'.empty ? null : '${list.example2}'.split(',')}")
    @Value("#{'${list.example}'.split(',')}")
    private List<String> list;

}

2.5 Array

array:
  example: array1,array2,array3

@Component
public class TestConfig {

    @Value("${array.example}")
    private String[] array;

}

3 Summary

type	Configuration method	Value method
literal	key: value	@Value("${key}")
object	example: object: '{"key1": "value1","key2": "value2"}'	@ConfigurationProperties(prefix = "example") public class TestConfig2 { private Object object; }
	example: object: key1: value1 key2: value2
array	example: array: array1,array2,array3	@Value("${example.array}")
List	example: list: - sheet 1 - list2 -list3	@ConfigurationProperties(prefix = "example") public class TestConfig2 { private List<String> list; }
	example: list: list1,list2,list3	@Value("#{'${list.example2}'.empty ? null : '${list.example2}'.split(',')}") @Value("#{'${list.example}'.split(',')}")
Map	map: example: '{"key1": "value1", "key2": "value2"}'	@Value("#{${map.example}}")
	example: map: key1: value1 key2: value2	@ConfigurationProperties(prefix = "example") public class TestConfig2 { private Map<String, String> map; }