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SpringBoot读写操作yml
yml配置规则
属性跟属性值之间使用“:”和一个“空格”隔开,层级结构通过缩进对齐,缩进只能使用空格,不能用tab,并且大小写敏感,使用#注释文档;
yml配置除了能像properties读取为kv结构,还能方便的读取成集合(List、Set等)、数组、对象、Map,还能进行嵌套结构读取;
普通的kv读取
普通kv结构可以直接使用@Value标签读取,@Value除了可以读取普通kv,也能读取List或Map结构里的某一项;另外使用Environment.getProperty()方法也能像properties那样读取kv结构,但也只能以kv结构读取;
yml格式:
xxx: xxxx
xxx:
xxx: xxxx
xxx:
xxx: xxxx
xxx: xxxx
xxx: xxxx
可以直接使用@Value("${xxx}")、@Value("${xxx.xxx.xxx}")读取;
读取到集合和数组
使用@Value直接读取好像只能使用xxx: xxxx,xxxx,xxxx逗号隔开的格式,可以读取成List、Set或者数组,其他格式可以放到Bean里当作类的属性读取;
yml格式:
xxx:
- xxxx
- xxxx
- xxxx
xxx: [xxxx,xxxx,xxxx]
xxx: xxxx,xxxx,xxxx
读取为对象和Map
对象和Map的格式是一样的,只是读取的目标不同;读取为对象时需要提供setXXX方法,并且XXX要跟配置文件里命名一致;(另外测试时发现自动生成的set方法,对驼峰结构修改大小写会造成无法识别到配置)
yml格式:
xxx:
x: xxxx
x: xxxx
x: xxxx
xxx: {x: xxxx, x: xxxx, x: xxxx}
另外各种格式可以组合嵌套使用,例如list里使用map或者map里包含list;
Demo:
yml配置文件application.yml:
#yml文件
a: hello
val:
b: 123
c: false
d: ENV
mybeantest:
name: Tom
age: 14
addr: 北京
bestfriend: ${myArrayA[3]}
mybeantest2: {name: Jerry, age: 13, id: 1001}
myArrayA:
- tom
- jerry
- jack
- alice
myArrayB: [a,b,c]
myListC: 3,4,5,6
myListD: [{name: Jerry, age: 11, addr: 上海},{name: Jack, age: 12, addr: 北京}]
myListE:
- {name: Bob, age: 22}
- {name: Lily, age: 21}
myListF:
- name: AAA
age: 11
- name: BBB
age: 22
myListG:
- - aaa
- bbb
- ccc
- - dd
- ee
- ff
maps:
mapA:
A: 1
B: 2
C: 3
D: 4
mapB:
a: AA
b: BB
c: CC
mapC: {X: x, Y: y, Z: z}
mapD:
L1:
- x
- y
- z
L2:
- X
- Y
- Z
mapE:
M1:
a: A
b: B
M2:
C: c
D: d
mapF:
m1: {name: TOM, age: 33}
m2: {name: JERRY, age: 44}
读取为bean的类MyBean.java和MyBean2.java:
package testspringboot.test3; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; @Component @ConfigurationProperties(prefix = "mybeantest") public class MyBean { public String name; public int age; public String address; public String bestFriend; public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public String getAddress() { return address; } public void setAddr(String address) {//setXXX方法,只需XXX跟配置文件里的名称对应即可(自动生成的set方法驼峰结构修改大小写会造成干扰) this.address = address; } public String getBestFriend() { return bestFriend; } public void setBestFriend(String bestFriend) { this.bestFriend = bestFriend; } @Override public String toString() { return "MyBean [name=" + name + ", age=" + age + ", address=" + address + ", bestFriend=" + bestFriend + "]"; } }
package testspringboot.test3; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; @Component @ConfigurationProperties(prefix = "mybeantest2") public class MyBean2 { public String name; public int age; public int id; public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public int getId() { return id; } public void setId(int id) { this.id = id; } @Override public String toString() { return "MyBean2 [name=" + name + ", age=" + age + ", id=" + id + "]"; } }
读取为集合的类MyList.java:
package testspringboot.test3; import java.util.List; import java.util.Set; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; @Component @ConfigurationProperties(prefix = "") public class MyList { public List<String> myArrayA; public Set<String> myArrayB; public Integer[] myListC; public List<MyBean> myListD; public List<MyBean> myListE; public List<MyBean> myListF; public List<List<String>> myListG; public List<String> getMyArrayA() { return myArrayA; } public void setMyArrayA(List<String> myArrayA) { this.myArrayA = myArrayA; } public Set<String> getMyArrayB() { return myArrayB; } public void setMyArrayB(Set<String> myArrayB) { this.myArrayB = myArrayB; } public Integer[] getMyListC() { return myListC; } public void setMyListC(Integer[] myListC) { this.myListC = myListC; } public List<MyBean> getMyListD() { return myListD; } public void setMyListD(List<MyBean> myListD) { this.myListD = myListD; } public List<MyBean> getMyListE() { return myListE; } public void setMyListE(List<MyBean> myListE) { this.myListE = myListE; } public List<MyBean> getMyListF() { return myListF; } public void setMyListF(List<MyBean> myListF) { this.myListF = myListF; } public List<List<String>> getMyListG() { return myListG; } public void setMyListG(List<List<String>> myListG) { this.myListG = myListG; } @Override public String toString() { return "MyList [myArrayA=" + myArrayA + ",\n myArrayB=" + myArrayB + ",\n myListC=" + myListC + ",\n myListD=" + myListD + ",\n myListE=" + myListE + ",\n myListF=" + myListF + ",\n myListG=" + myListG + "]"; } }
读取为Map的类MyMap.java:
package testspringboot.test3; import java.util.List; import java.util.Map; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; @Component @ConfigurationProperties(prefix = "maps") public class MyMap { public Map<String, Integer> mapA; public Map<String, String> mapB; public Map<String, String> mapC; public Map<String, List<String>> mapD; public Map<String, Map<String, String>> mapE; public Map<String, MyBean2> mapF; public Map<String, Integer> getMapA() { return mapA; } public void setMapA(Map<String, Integer> mapA) { this.mapA = mapA; } public Map<String, String> getMapB() { return mapB; } public void setMapB(Map<String, String> mapB) { this.mapB = mapB; } public Map<String, String> getMapC() { return mapC; } public void setMapC(Map<String, String> mapC) { this.mapC = mapC; } public Map<String, List<String>> getMapD() { return mapD; } public void setMapD(Map<String, List<String>> mapD) { this.mapD = mapD; } public Map<String, Map<String, String>> getMapE() { return mapE; } public void setMapE(Map<String, Map<String, String>> mapE) { this.mapE = mapE; } public Map<String, MyBean2> getMapF() { return mapF; } public void setMapF(Map<String, MyBean2> mapF) { this.mapF = mapF; } @Override public String toString() { return String.format("MyMap [mapA=%s,\n mapB=%s,\n mapC=%s,\n mapD=%s,\n mapE=%s,\n mapF=%s]", mapA, mapB, mapC, mapD, mapE, mapF); } }
进行测试用的类Test3Class.java:
package testspringboot.test3; import java.util.List; import java.util.Set; import javax.annotation.PostConstruct; import javax.annotation.Resource; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.core.env.Environment; import org.springframework.stereotype.Component; @Component public class Test3Class { @Value("${a}") public String a; @Value("${val.b}") public int b; @Value("${val.c}") public boolean c; @Autowired public Environment env; @Resource public MyBean bean; @Resource public MyBean2 bean2; @Value("${myArrayA[3]}") public String arrayA_3; @Value("${myArrayB[1]}") public String arrayB_1; @Value("${myListC}") public List<Integer> list; @Value("${myListC}") public Set<String> set; @Value("${myListC}") public String[] array; @Resource public MyList mylist; @Resource public MyMap mymap; @PostConstruct public void fun() { System.out.println(a); System.out.println(b); System.out.println(c); System.out.println(env.getProperty("val.d")); System.out.println(bean); System.out.println(bean2); System.out.println(arrayA_3); System.out.println(arrayB_1); System.out.println(list); System.out.println(set); System.out.println(array); System.out.println(mylist); System.out.println(mymap); } }
启动类(只测配置文件,所以设置WebApplicationType.NONE关闭web服务):
package testspringboot.test3; import org.springframework.boot.SpringApplication; import org.springframework.boot.WebApplicationType; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class Test3Main { /** * @param args */ public static void main(String[] args) { SpringApplication sapp = new SpringApplication(Test3Main.class); sapp.setWebApplicationType(WebApplicationType.NONE); sapp.run(args); } }
执行结果:
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