A, Spring Boot entry

1.Spring Boot Profile

A simplified framework for Spring application development

Spring a large integration of the entire technology stack

J2EE development of one-stop solution

2. Micro Services

2014，martin fowler

Micro services: architecture style

An application should be a set of small service; can communicate by way of Http

Each functional element is an independent final alternative and independent means software upgrade

detailed

3. Environmental constraints

-jdk1.7 and above 1.8.0_112

-maven3.3 3.3.9 and above

-IntelliJIDEA2017

-Spring Boot1.5.9

1.MAVEN settings.xml

<profile>   
    <id>jdk1.8</id>    
    <activation>   
        <activeByDefault>true</activeByDefault>    
        <jdk>1.8</jdk>   
    </activation>    
    <properties>   
        <maven.compiler.source>1.8</maven.compiler.source>    
        <maven.compiler.target>1.8</maven.compiler.target>    
        <maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion>   
    </properties>   
</profile>

2.IDEA settings

maven home directory

user settings files

4.Spring Boot Helloword

1. Create a Maven project

2. Related dependence introduced Spring Boot

<parent>    
 <groupId>org.springframework.boot</groupId>    
 <artifactId>spring-boot-starter-parent</artifactId>    
  <version>1.5.9.RELEASE</version>
</parent>

<dependencies>
  <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
</dependencies>

3. Write a main program: Start Spring Boot

/**
 *  @SpringBootApplication 来标注一个主程序，说明这是一个Spring Boot应用
 */
@SpringBootApplication
public class HelloApp {
    public static void main(String[] arge){
        
        //Spring 应用启动起来
        SpringApplication.run(HelloApp.class,arge);
    }
}

4. Write Controler, Service

@Controller
public class HelloController {

    @ResponseBody
    @RequestMapping("/hello")
    public String hello(){
        return "Hello World";
    }
}

5. Test run the main program

6. Simplify deployment

<!-- 这个插件，可将应用打包成一个可执行的jar包 -->
<build>
    <plugins>
      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
      </plugin>
    </plugins>
  </build>

This application will be labeled jar package, the direct use of java -jar command execution

5.Hello World Exploration

1.POM file

1. Parent Project

<parent>  
    <groupId>org.springframework.boot</groupId>  
    <artifactId>spring-boot-starter-parent</artifactId>  
    <version>1.5.9.RELEASE</version>
</parent>

<!-- 它的父项目是 -->
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-dependencies</artifactId>
    <version>1.5.9.RELEASE</version>
    <relativePath>../../spring-boot-dependencies</relativePath>
</parent>
<!-- 它来真正管理Spring Boot应用里面的所有依赖版本 -->

Spring Boot version Arbitration Center

After we import dependence is no need to write the default version; (there is no need to declare the dependencies naturally inside the administration in)

2. Import dependence

<dependency>                        
    <groupId>org.springframework.boot</groupId>  
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

spring-boot-starter-web：

spring-bot-starter: spring-boot scene initiator; help us introducing the web assembly module is operating normally depend

Spring-Boot all the features scenes are extracted, made a number of starters (starter), only need to import the starter in the project, all depend on the relevant scenes are imported come

2 of the main program, the main entrance class

/**
 *  @SpringBootApplication 来标注一个主程序，说明这是一个Spring Boot应用
 */
@SpringBootApplication
public class HelloApp {
    public static void main(String[] arge){

        //Spring 应用启动起来
        SpringApplication.run(HelloApp.class,arge);
    }
}

@SpringBootApplication: Spring Boot application is marked on a class, indicating that this class is SpringBoot master class configuration, SpringBoot you should run the main method of this class of applications to start SpringBoot

@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@SpringBootConfiguration
@EnableAutoConfiguration
@ComponentScan( excludeFilters = {
    @Filter( type = FilterType.CUSTOM, classes = {TypeExcludeFilter.class}),                
    @Filter( type = FilterType.CUSTOM, classes ={AutoConfigurationExcludeFilter.class})})
public @interface SpringBootApplication {

@ SpringBootConfiguration : the Spring the Boot configuration class:

Marked on a class, he said it was a SpingBoot configuration class

@ The Configuration : configuration class marked up this comment

Configuration class ...... Profiles: class is a container set up: @Component

@ EnableAutoConfiguration : turn on auto-configuration feature;

Things before we need to configure, SpringBoot help us configure; @ EnableAutoConfiguration tell us SpringBoot open the automatic configuration feature; this command will take effect automatically;

@AutoConfigurationPackage
@Import({EnableAutoConfigurationImportSelector.class})
public @interface EnableAutoConfiguration {

@ AutoConfigurationPackage : Automatic configuration package

@Import({Registrar.class})

Spring's annotation @import, introduced into a container to assembly; import component Registrar.class

Where all components of all primary package configuration class (@SpringBootApplication class label) and the lower sub-packets of scanned Spring container inside;

@Import({EnableAutoConfigurationImportSelector.class})：

Import component to the container

EnableAutoConfigurationImportSelector: which introduced the selector assembly;

All of the components needed to return the introduced full class name manner; these components will be added to the container;

It will import container configuration comes with a lot of class (xxxAutoConfiguration); this scene is to import all the components required for container and configure these components;

With automatic configuration class, eliminating the need to manually write the configuration work we inject functional components;

SpringFactoriesLoader.loadFactoryNames(EnableAutoConfiguration.class, ClassLoader);

SpringBoot at boot time, specified EnableAutoConfiguration obtain the value from the META-INF / spring.factories class path, the autoconfiguration these values as class into a container, automatically configured based on force, work for us automatically configured; we need to own something before configuration, automatic configuration class to help us;

J2EE overall integration solutions and automatic configuration are spring-boot-autoconfigure-1.5.9.RELEASE.jar in;

6. Spring Boot quickly create a project using Spring Initislizer

IDE support the creation wizard to quickly create a project using Spring Spring Boot project;

Select the module we need; networking wizard created SpringBoot project;

Farmer generated Spring Boot project:

The main program has generated good, just need to write their own logic
resources folder directory structure
- static: Save all static resources; js css images;
- templates: Save all template pages; (Spring Boot default jar package using an embedded tomcat, the default does not support JSP page); you can use a template engine (freemarker, thymeleaf)
- application.properties:SpringBoot application configuration file; you can modify some of the default settings

Spring Boot learning --- 01