SpringBoot讀寫操作yml配置文件方法

更新時(shí)間：2023年01月19日 08:30:21 作者：FlyLikeButterfly

之前一直用的application.properties配置文件，只能是KV結(jié)構(gòu)，后來的yml配置文件更像是樹狀結(jié)構(gòu)，支持層級(jí)，比properties更靈活

yml配置規(guī)則

屬性跟屬性值之間使用“:”和一個(gè)“空格”隔開，層級(jí)結(jié)構(gòu)通過縮進(jìn)對(duì)齊，縮進(jìn)只能使用空格，不能用tab，并且大小寫敏感，使用#注釋文檔；

yml配置除了能像properties讀取為kv結(jié)構(gòu)，還能方便的讀取成集合（List、Set等）、數(shù)組、對(duì)象、Map，還能進(jìn)行嵌套結(jié)構(gòu)讀??；

普通的kv讀取

普通kv結(jié)構(gòu)可以直接使用@Value標(biāo)簽讀取，@Value除了可以讀取普通kv，也能讀取List或Map結(jié)構(gòu)里的某一項(xiàng)；另外使用Environment.getProperty()方法也能像properties那樣讀取kv結(jié)構(gòu)，但也只能以kv結(jié)構(gòu)讀取；

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}")讀?。?/p>

讀取到集合和數(shù)組

使用@Value直接讀取好像只能使用xxx: xxxx,xxxx,xxxx逗號(hào)隔開的格式，可以讀取成List、Set或者數(shù)組，其他格式可以放到Bean里當(dāng)作類的屬性讀??；

yml格式：

xxx:
- xxxx
- xxxx
- xxxx
xxx: [xxxx,xxxx,xxxx]
xxx: xxxx,xxxx,xxxx

讀取為對(duì)象和Map

對(duì)象和Map的格式是一樣的，只是讀取的目標(biāo)不同；讀取為對(duì)象時(shí)需要提供setXXX方法，并且XXX要跟配置文件里命名一致；（另外測(cè)試時(shí)發(fā)現(xiàn)自動(dòng)生成的set方法，對(duì)駝峰結(jié)構(gòu)修改大小寫會(huì)造成無法識(shí)別到配置）

yml格式：

xxx:
x: xxxx
x: xxxx
x: xxxx
xxx: {x: xxxx, x: xxxx, x: xxxx}

另外各種格式可以組合嵌套使用，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}

讀取為bean的類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跟配置文件里的名稱對(duì)應(yīng)即可（自動(dòng)生成的set方法駝峰結(jié)構(gòu)修改大小寫會(huì)造成干擾）
		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 + "]";
	}
}

讀取為集合的類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 + "]";
	}
}

讀取為Map的類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);
	}
}

進(jìn)行測(cè)試用的類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);
	}
}

啟動(dòng)類（只測(cè)配置文件，所以設(shè)置WebApplicationType.NONE關(guān)閉web服務(wù)）：

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);
	}
}

執(zhí)行結(jié)果：