JT Jingtao project

1. Jingtao project architecture design

1.1 The characteristics of the Internet industry

1. High concurrency
2. Distributed The number of servers is evenly distributed
3. Massive data processing （ Big data direction ）
4. Security issues : Net loan (11%) Security of transactions ( Blockchain )

1.2 Jingtao project architecture design

2. preparation

2.1 Software ：（IDEA、MariaDB【sqlyog】）

2.2 The configuration file

1.pom.xml（springboot——Demo1）

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    
    <!--1.parent The role of labels ***
  effect ：
 1： Resolve version conflicts 
 2： It's a polymerization project （pom）
 -->
 <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.5.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
 </parent>
 
    <!--2.maven coordinate ***
 maven Project identification ： Group Id/ Project name / Version number    be called maven coordinate 
  effect ：
 1：  In the form of coordinates 
 2：  In local warehouse  jar The location of the package is the position of the coordinates ,maven Work performed by coordinate lookup jar
 --> <groupId>com.jt</groupId>
    <artifactId>springboot_demo01</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springboot_demo01</name>
    <description>Demo project for Spring Boot</description>
    
    <!--3.maven Project configuration information ***
 --> <properties>
        <!-- It specifies jdk Version information -->
 <java.version>1.8</java.version>
        <!--
  Skip test class packaging 
  By default, the program package will execute the test class   If there is a problem with the test class , The program package fails .
 --> <skipTests>true</skipTests>
    </properties>
    
    <!--4. rely on 
  Manual dependencies   The dependency is springBoot Highly integrated 
 springBoot Help you to dynamically generate configuration items , Simplified configuration steps 
  This configuration is called automated configuration information   Open the box :  Just import jar Package simple configuration can achieve the corresponding function .
 --> <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    
    <!--5.maven  Plug in description 
 SpringBoot utilize maven Management tools for project packaging / Release / Wait for the operation 
  The tag must be added with  -->
 <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

1. properties explain

1. grammar : k-v structure  key=value
2. data type :  The default is String data type   Don't add extra "" Number 
3. Character data type : properties The default encoding format for loading is ISO-8859-1  Therefore, adding Chinese requires character translation .
4. shortcoming :  be-all key All have to be edited manually   There is no way to reuse   So we introduced yml To configure 

1. YML Profile description

1. grammar  K-V structure   In writing  key:value  In essence  key=value
key:value In the middle  (:+ Space )  Separate 
key And key Having a father-child relationship .  So pay attention to indents when writing .
YML The default format of configuration files is UTF-8 code   So you can edit Chinese directly 

1. SpringBoot Environment switching problem

#  The configuration file , When spring Load when container starts .
spring:
  profiles:
    active: prod
---

#  Define the development environment 
spring:
  profiles: dev

server:
  port: 8080

# To configure redis Node information 
redis:
  host: 192.168.1.100
  port: 6379

#  If you need to configure multiple environments, you need to set YML Environment segmentation 
---
spring:
  profiles: prod

server:
  port: 8090

# To configure redis Node information 
redis:
  host: 10.0.0.1
  port: 6379

5.@Value Annotation attribute assignment
explain : because YML The configuration file is generally used to configure the third party's integrated information , If you add business data to YML China is not standardized . It's better to add business operations to properties In file .

@RestController        //@ResponseBody  Convert the return value to json String use   The program will not execute the view parser   Go straight back to 
//@Controller          //String type /moduleAndView
public class RedisController {

    /**
     *  Realize the idea :
     *    If you can get data from the container , Assign directly to the property . Then decoupling can be achieved 
     *  How to achieve :
     *       Annotation implementation : @Value("${ Profile's key}")
     *  expression :  spel  expression 
     */

    @Value("${redis.host}")
    private String host;
    @Value("${redis.port}")
    private Integer port;

    // If you use RestController  The return value is String Type returns the string itself 
    // If an object is returned   Then the result must be that of the object JSON data .
    @RequestMapping("/getMsg")
    public String getMsg(){

        return host + ":" + port;
    }
}