SpringBoot入门7_综合

参考：Spring Boot 2.0深度实践之系列总览

核心特性

组件自动装配：模式注解、@Enable模块、条件装配、加载机制

外部化配置：Environment抽象、生命周期、破坏性变更。

嵌入式容器：Servlet Web容器、Reactive Web容器

Spring Boot Starter:依赖管理、装配条件、装配顺序

Production-Ready:健康检查、数据指标、@Endpoint管控

SpringBoot与Java EE规范

Web	Servlet(JSR-315，JSR-340)
SQL	JDBC(JSR-221)
数据校验	Bean Validation(JSR303,JSR-349)
缓存	Java Caching API (JSR-107)
WebSockets	Java API for WebSocket(JSR-356)
Web Services	JAX-WS(JSR-224)
Java 管理	JMX(JSR 3)
消息	JMS(JSR-914)

组件自动装配

激活：@EnableAutoConfiguration

配置：/META-INF/spring.factories

实现：XXXAutoConfiguration

创建一个项目

生产准备特性

指标：/actuator/metrics

健康检查： /actuator/health

外部化配置：/actuactor/configprops

传统Servlet应用

Servlet组件：Servlet,Filter, Listener

Servlet注册：Servlet注解、Spring Bean, RgistrationBean

异步非阻塞：异步Servlet，非阻塞Servlet

1、pom.xml中依赖

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

2、代码..web.servlet.MyServlet.java

package com.imooc.diveinspringboot.web.servlet;import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;@WebServlet(urlPatterns = "/my/servlet")
public class MyServlet extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//		super.doGet(req, resp);resp.getWriter().print("Hello World!!!");}
}

3、在DiveInSpringBootApplication.java中注册

@SpringBootApplication
@ServletComponentScan(basePackages = "com.imooc.diveinspringboot.web.servlet")
public class DiveInSpringBootApplication {public static void main(String[] args) {SpringApplication.run(DiveInSpringBootApplication.class, args);}
}

异步Servlet

代码..web.servlet.MyServletAsync.java

@WebServlet(urlPatterns = "/my/servletasync",asyncSupported = true)
public class MyServletAsync extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {AsyncContext asyncContext = req.startAsync();asyncContext.start(()->{try {resp.getWriter().print("Hello World!!!");asyncContext.complete(); //触发完成；} catch (IOException e) {e.printStackTrace();}});}
}

Spring Web MVC应用

Web MVC 视图：模板引擎、内容协商、异常处理等

Web MVC REST：资源服务、资源跨域、服务发现等

Web MVC核心：核心架构、处理流程、核心组件

1、ViewResolver、view

Spring Web Flux应用

Reactor基础：Java Lambda，Mono,Flux

Web Flux核心：Web MVC注解，函数声明，异步非阻塞

使用场景：Web Flux优势和限制

Web Server应用

切换Web Server

自定义Servlet Web Server

自定义 Reactive Web Server

1、Tomcat切换为Jetty,pom.xml依赖

        <dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId><exclusions><!-- Exclude the Tomcat dependency --><exclusion><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-tomcat</artifactId></exclusion></exclusions></dependency><!-- Use Jetty instead --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-jetty</artifactId></dependency>

2、替换为WebFlux容器。

需要注释Web容器，因为Web容器的优先级高。

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

Nettystart

自定义 Servlet Web Server
WebServerFactoryCustomizer
自定义 Reactive Web Server
ReactiveWebServerFactoryCustomizer

关系型数据

JDBC:数据源, JdbcTemplate, 自动装配

JPA：实体映射关系，实体操作，自动装配

事务： Spring事务抽象，JDBC事务处理，自动装配

1、JDBC POM.xml依赖

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

2、JPA POM.xml依赖

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

事务

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
</dependency>

Spring Boot应用

SpringApplication:失败分析，应用特性，事件监听等

Spring Boot配置：外部化配置，Profile, 配置属性

Spring Boot Starter: Starter开发，最佳实践

Spring Boot Actuator 运维管理

端点：各类Web和JMX Endpoints

健康检查：Health, HealthIndicator

指标：内建Metrics, 自定义Metrics

1、Pom.xml依赖

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

2、Java Mission Control

3、开放所有的端点，配置application.yml

# 开放索引的 Web Endpoints
management:endpoints:web:exposure:include: '*'