Spring Boot QuickStart (i)

1. Installation and use of IDE tools

• 1.1. Download IDE

  • Spring Tool Suite
  • Eclipse

• 1.2. Introduction

  • MAVEN is one of the prerequisites for learning Spring boot
  • Spring Tool Suite to quickly build a spring boot project
• 1.3. Spring Boot Project Structure preview
  

2, Restfull API Simple Project Quick Build

• 2.1. Build a simple Restfull API interface Project
  

• 2.2. Introduction of Spring-boot-starter-web
  

• 2.3. Introduction of Spring-boot-devtools
  

• 2.4, the implementation of the Code

  User.java:

  import java.util.Date;/** * 实体类 */public class User {    private int id;    private String name;    private Date date;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public Date getDate() {        return date;    }    public void setDate(Date date) {        this.date = date;    }}

  Indexcontroller.java:

  Import Java.util.date;import Java.util.hashmap;import Org.springframework.web.bind.annotation.pathvariable;import Org.springframework.web.bind.annotation.requestmapping;import Org.springframework.web.bind.annotation.requestparam;import Org.springframework.web.bind.annotation.restcontroller;import com.roncoo.education.bean.user;/** *    spring-boot-demo-2-1 */@RestController @requestmapping (value = "/index") public class Indexcontroller {@RequestMapping    Public String Index () {return ' Hello World '; }//@RequestParam a simple type of binding that can come out get and post @RequestMapping (value = "/get") public hashmap<string, object> get (        @RequestParam String name) {hashmap<string, object> map = new hashmap<string, object> ();        Map.put ("title", "Hello World");        Map.put ("name", name);    return map; }//@PathVariable get the dynamic parameter in the request URL @RequestMapping (value = "/get/{id}/{name}") Public User GetUser (@PathVariable in      T ID, @PathVariable String name) {  User user = new user ();        User.setid (ID);        User.setname (name);        User.setdate (New Date ());    return user; }}

• 2.5. Running the project

  • Run the main method directly or use the MAVEN command:spring-boot:run
  • Test:http://localhost:8080/index
  • With parameters:http://localhost:8080/index/get?name=wujing
  • With the parameters are in Chinese:http://localhost:8080/index/get?name=测试
  • URL test:http://localhost:8080/index/get/1/wujing
  • URL test:http://localhost:8080/index/get/1/测试
• 2.6. Packing
  • Command: clean package
    
    
  • To run the command:java –jar roncoo-education-0.0.1-SNAPSHOT.jar

3. Detailed configuration file: Properties and Yaml

• 3.1, the configuration file effective order, the value will be overwritten:

  • 1. @TestPropertySource annotations
  • 2. Command-line arguments
  • 3.Java System Properties ( System.getProperties() )
  • 4. Operating system Environment variables
  • 5. Only the random.* attributes contained within will produce aRandomValuePropertySource
  • 6. Application configuration file (with application.properties Yaml and profile variables) outside the packaged jar
  • 7. Application configuration file ( application.properties containing YAML and profile variables) within the packaged jar
  • 8. @Configuration annotations on the class @PropertySource
  • 9. Default properties (using SpringApplication.setDefaultProperties specified)

• 3.2, configure the random value (custom, only restart the project will regenerate random values)

  roncoo.secret=${random.value}roncoo.number=${random.int}roncoo.bignumber=${random.long}roncoo.number.less.than.ten=${random.int(10)}roncoo.number.in.range=${random.int[1024,65536]}

  • Read using annotations:@Value(value = "${roncoo.secret}")
  • Note: The yellow dot hint is to prompt for configuration metadata, you can not configure

• 3.3. Attribute placeholders

  When values in Application.properties are used, they are filtered by the presence of environment, so you can refer to previously defined values (for example, System Properties).

  roncoo.name=www.roncoo.comroncoo.desc=${roncoo.name} is a domain name

• 3.4, Application Property files, sorted by priority, high position will cover the low position

  • 1. A subdirectory under the current directory /config
  • 2. Current directory
  • 3. One classpath under the /config package
  • 4. classpath Root Path ( root -Default build path)
  • This list is sorted by priority (the high position in the list will have a low coverage position)

• 3.5. Introduction to configuring Application ports and other configurations

  #端口配置：server.port=8090#时间格式化spring.jackson.date-format=yyyy-MM-dd HH:mm:ss#时区设置(若使用jackson格式化时间字符串需设置本地时区,默认是美国的时区)spring.jackson.time-zone=Asia/Chongqing

• 3.6. Use Yaml instead of properties
  • Note: Add a space after the colon

4. Configuration file-Multi-environment configuration

• 4.1. Benefits of multi-environment configuration

  • 1. Different environment configuration can be configured with different parameters
  • 2. Easy to deploy, improve efficiency, reduce errors

• 4.2, the properties of multi-environment configuration

  • 1. Configure activation options
    • spring.profiles.active=dev
  • 2. Add additional Profiles
    

• 4.3. YAML Multi-environment configuration
  ① Configuring activation options

  spring:  profiles:    active: dev

  ② add three English-language dashes in the configuration file to differentiate between different files

  ---spring:  profiles: dev

• 4.4. Comparison of two configuration methods

  • 1.Properties Configure multi-environment, need to add multiple configuration files, Yaml only need one accessory file
  • 2. The difference in writing format, Yaml relatively concise, elegant
  • Disadvantages of 3.YAML: cannot be @PropertySource loaded by annotations. If you need to @PropertySource load values using annotations, use the properties file.
• 4.5. Operation and use
  • java -jar myapp.jar --spring.profiles.active=dev

5. List of acknowledgements

• Feng Yongwei

Spring Boot QuickStart (i)