spring-boot study two: Spring boot configuration related content

1. Profiles

1.1 brief

spring boot by default will use a global configuration file, the configuration file can be in two formats of files, one is .properties, one is .yaml format files; and the name of the configuration file is fixed, either application. properties, either application.yaml;

Profile role: Spring Boot modify the default values ​​configured, for example, the port number and the like;

1.2YAML grammar Introduction

1.2.1 Introduction

YAML: (YAML Is not Markup Lanuage), the popular name has two meanings:

YAML A Markup Lanuage: YAML is a markup language;

YAML is not Markup Lanuage: YAMA is not a markup language;

YAML data-centric than json.xml more suitable for the configuration file;

For example, we want to change the port information of the start of spring boot, we application.properties file syntax is as follows:

server.port=8971

However application.yaml file syntax is as follows:

server:
  port: 8089

Of course, if we have the same work in XML configuration file, the syntax is as follows:

<server>
<port>8089</port>
</server>

 1.2.2 concrete syntax

[1] k :( space) v: designates a pair of key-value pairs (there must be a space), with spaces to indent control hierarchy; as long as one is left-aligned data, are of the same level; 

 

server:
  port: 8089
  error:
    path: /hello

 

Wherein the first level is a server, port and belong to the same error level, path belonging to a single level;

It is also to be noted that, yaml file attributes and values ​​case-sensitive;

 

[2] written value

That is all what value can be written in yaml file, our common values ​​types are as follows:

The first category: literal, Common values ​​(numbers, strings, Boolean)

             k: v: literal directly to write, especially for string types without adding double quotes, double quotes if there is a special meaning, from strings of special characters special meaning output, such as output "ab \ nc", output:　　

ab
c

If you add a single quotation mark, then the special characters will be output as, for example: 'ab \ nc' output is:

ab \n c

The second category: objects, map (attributes and values) (key-on);

　　　k: v: to write the next line object relationship attributes and values, attention indent; for example, we now have a class User, which has the properties name and age written as follows:

user:
    name: haige
    age: 20

　　Above this wording also equivalent to the line following wording:

User{name: haige,age: 20}

 

The third category: the collection array (List, Set);

 　　Represents an element in the array values, for example below sets pets, there are a set of original pixel - with: pig, dog, cat worded as follows:

pets:
    -pig
    -dog
    -cat

Writing said further line is equivalent to the wording of this following:

pets: [pig,cat,dog]

 1.3 injecting property value from the configuration file YAML

Since YAML configuration file so convenient that we need to learn to read properties from a YAML file. Here, an example presentation;

Specific steps are as follows:

[Step 1]: the Person class declaration, there are attributes name, age, map set, list collection, objects and other attributes;

package com.hai.bao.springboot01;

import java.util.Date;
import java.util.List;
import java.util.Map;

/**
 * @author ：haibao.wang
 * @date ：Created in 2019/8/29 22:20
 * @description：person类
 * @modified By：
 * @version: $
 */
public class Person {
    private String name;
    private int age;
    private boolean boss;
    private Date birth;
    private Map<String, Object> maps;
    private List<Object> lists;
    private Dog dog;

    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 boolean isBoss() {
        return boss;
    }

    public void setBoss(boolean boss) {
        this.boss = boss;
    }

    public Date getBirth() {
        return birth;
    }

    public void setBirth(Date birth) {
        this.birth = birth;
    }

    public Map<String, Object> getMaps() {
        return maps;
    }

    public void setMaps(Map<String, Object> maps) {
        this.maps = maps;
    }

    public List<Object> getLists() {
        return lists;
    }

    public void setLists(List<Object> lists) {
        this.lists = lists;
    }

    public Dog getDog() {
        return dog;
    }

    public void setDog(Dog dog) {
        this.dog = dog;
    }

    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", boss=" + boss +
                ", birth=" + birth +
                ", maps=" + maps +
                ", lists=" + lists +
                ", dog=" + dog +
                '}';
    }
}

Person class which has a class attribute Dog, Dog class as follows:

package com.hai.bao.springboot01;

/**
 * @author ：haibao.wang
 * @date ：Created in 2019/8/29 22:23
 * @description：新建一个小狗类
 * @modified By：
 * @version: $
 */
public class Dog {
    private String dogName;
    private int dogAge;

    public String getDogName() {
        return dogName;
    }

    public void setDogName(String dogName) {
        this.dogName = dogName;
    }

    public int getDogAge() {
        return dogAge;
    }

    public void setDogAge(int dogAge) {
        this.dogAge = dogAge;
    }
}

[2] configuration attribute value associated application.yaml in the Person class file;

Server: 
  Port: 8089 
Person: 
  name: Haige 
  Age: 18 is 
  BOSS: to true 
  Birth: 1990/05/27 
  Maps: 
    key01: Chemical 
    key02: Physical 
  Lists: 
    - Running 
    - Swimming 
  Dog: 
    dogName: Cai 
    dogAge: 3

 

 

 

 

 [3] At this time there is a message in the Person class:

 

 

 At this time, the processor needs to be added in the profile pom.xml file, as dependent;

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-configuration-processor</artifactId>
    <optional>true</optional>
</dependency>

 [4] Person class to add @ConfigurationProperties (prefix = "Person") notes. Tell Spring boot configuration information for all the properties and configuration files in this class bind one by one;

 

 

 

 [5] Person class to add annotations container, ensure that the components in the container, it can be used @ConfigurationProperties annotations;

 

 

 

 [6] Start Spring boot services;

[7] to write a test class Spring boot unit to verify the feature:

package com.hai.bao;

import com.hai.bao.springboot01.Person;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class BaoApplicationTests {
    @Autowired
    Person person;

    @Test
    public void contextLoads() {
        System.out.println(person);
    }

}

Code results are as follows:

 

1.4 .properties file to configure attributes of the Person class;

# Configure the Person class-related property values 
person.age = 10 
person.birth = 1990 / 05 / 01 
person.boss = to true 
person.maps.key01 = mathematics 
person.maps.key02 = chemical 
person.lists = yoga, swimming 
person .dog.dogName = Cai 
person.dog.dogAge = 2

 

 After starting the execution unit testing, the test results are as follows:

 

 Garbled, because the method IDEA native coding format utf-8, to solve distortion problems are as follows:

File-settings-File Encodings