Spring Boot实战学习笔记2

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title: Spring Boot实战学习笔记2
tags:Spring Boot实战
grammar_cjkRuby: true

---

摘要

本文为学习Spring Boot实战的学习笔记,学习了一遍,但是好记性不如烂笔头,所以文章记录下来。图书购买地址为: https://item.jd.com/11894632.html.

Spring Boot实战学习笔记1

Spring Boot实战学习笔记2

Spring Boot实战学习笔记3

Spring Boot实战学习笔记4

Spring Boot实战学习笔记5

1.Spring 基础

2.Spring 常用配置

3.Spring 高级话题

4.Spring mvc基础

4.1 Spring mvc概述

MVC:Model+View+Controller(数据模型+视图+控制器) V有:jsp,freemark,velocity,Thymeleaf,Tile.
三层架构: Presentiont tier+Application tier+Data tier.(展示层+应用层+数据访问层)

4.2 Spring mvc项目快速搭建

Spring mvc源码路径如下:highlight_springmvc4工程中的com.wisely.highlight_springmvc4下.//maven中需要的依赖如下//highlight_springmvc4/pom.xml<dependency>            <groupId>javax</groupId>            <artifactId>javaee-web-api</artifactId>            <version>7.0</version>            <scope>provided</scope>        </dependency>        <!-- Spring MVC -->        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-webmvc</artifactId>            <version>${spring-framework.version}</version>        </dependency>        <!-- 其他web依赖 -->        <dependency>            <groupId>javax.servlet</groupId>            <artifactId>jstl</artifactId>            <version>${jstl.version}</version>        </dependency>        <dependency>            <groupId>javax.servlet</groupId>            <artifactId>javax.servlet-api</artifactId>            <version>${servlet.version}</version>            <scope>provided</scope>        </dependency>        <dependency>            <groupId>javax.servlet.jsp</groupId>            <artifactId>jsp-api</artifactId>            <version>${jsp.version}</version>            <scope>provided</scope>        </dependency>        <!-- Spring and Transactions -->        <dependency>            <groupId>org.springframework</groupId>            <artifactId>spring-tx</artifactId>            <version>${spring-framework.version}</version>        </dependency>        <!-- 使用SLF4J和LogBack作为日志 -->        <dependency>            <groupId>org.slf4j</groupId>            <artifactId>slf4j-api</artifactId>            <version>${slf4j.version}</version>        </dependency>        <dependency>            <groupId>log4j</groupId>            <artifactId>log4j</artifactId>            <version>1.2.16</version>        </dependency>        <dependency>            <groupId>org.slf4j</groupId>            <artifactId>jcl-over-slf4j</artifactId>            <version>${slf4j.version}</version>        </dependency>        <dependency>            <groupId>ch.qos.logback</groupId>            <artifactId>logback-classic</artifactId>            <version>${logback.version}</version>        </dependency>        <dependency>            <groupId>ch.qos.logback</groupId>            <artifactId>logback-core</artifactId>            <version>${logback.version}</version>        </dependency>        <dependency>            <groupId>ch.qos.logback</groupId>            <artifactId>logback-access</artifactId>            <version>${logback.version}</version>        </dependency>        <!--对json和xml格式的支持 -->        <dependency>            <groupId>com.fasterxml.jackson.dataformat</groupId>            <artifactId>jackson-dataformat-xml</artifactId>            <version>2.5.3</version>        </dependency>        <!-- file upload -->        <dependency>            <groupId>commons-fileupload</groupId>            <artifactId>commons-fileupload</artifactId>            <version>1.3.1</version>        </dependency>        <!-- 非必需，可简化IO操作 -->        <dependency>            <groupId>commons-io</groupId>            <artifactId>commons-io</artifactId>            <version>2.3</version>        </dependency>

//highlight_springmvc4/src/main/resources/logback.xml

<?xml version="1.0" encoding="UTF-8"?><configuration scan="true" scanPeriod="1 seconds">    <contextListener class="ch.qos.logback.classic.jul.LevelChangePropagator">        <resetJUL>true</resetJUL>    </contextListener>    <jmxConfigurator/>    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">        <encoder>            <pattern>logbak: %d{HH:mm:ss.SSS} %logger{36} - %msg%n</pattern>        </encoder>    </appender>      <logger name="org.springframework.web" level="DEBUG"/> <!-- 1 -->    <root level="info">        <appender-ref ref="console"/>    </root></configuration>

JSP所在位置:highlight_springmvc4/src/main/resources/views/index.jsp
springMVC配置:

//本例中包含了本节及后面章节的代码. 用到哪里介绍哪里.@Configuration@EnableWebMvc// 1@EnableScheduling@ComponentScan("com.wisely.highlight_springmvc4")public class MyMvcConfig extends WebMvcConfigurerAdapter {// 2    //4.2 设置jsp后缀及jsp路径    @Bean    public InternalResourceViewResolver viewResolver() {        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();        viewResolver.setPrefix("/WEB-INF/classes/views/");        viewResolver.setSuffix(".jsp");        viewResolver.setViewClass(JstlView.class);        return viewResolver;    }    //4.4.1 静态资源映射    //assets/** 对外访问路径    //classpath:/assets/ 文件所在路径. /src/main/resources/assets    @Override    public void addResourceHandlers(ResourceHandlerRegistry registry) {        registry.addResourceHandler("/assets/**").addResourceLocations(                "classpath:/assets/");// 3    }    //4.4.2 配置拦截器Bean,和4.4.2 DemoInterceptor搭配使用    @Bean    // 1    public DemoInterceptor demoInterceptor() {        return new DemoInterceptor();    }    //4.4.2 重写addInterceptors,注册拦截器    @Override    public void addInterceptors(InterceptorRegistry registry) {// 2        registry.addInterceptor(demoInterceptor());    }    //4.4.4-1 ViewControllers写法    @Override    public void addViewControllers(ViewControllerRegistry registry) {        registry.addViewController("/index").setViewName("/index");        registry.addViewController("/toUpload").setViewName("/upload");        registry.addViewController("/converter").setViewName("/converter");        registry.addViewController("/sse").setViewName("/sse");        registry.addViewController("/async").setViewName("/async");    }    //4.4.4-2 路径匹配参数配置     @Override     public void configurePathMatch(PathMatchConfigurer configurer) {     configurer.setUseSuffixPatternMatch(false);     }    //4.5.1 文件上传    @Bean    public MultipartResolver multipartResolver() {        CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver();        multipartResolver.setMaxUploadSize(1000000);        return multipartResolver;    }    //4.5.2 自定义HttpMessageConverter    @Override    public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {        converters.add(converter());    }    //4.5.2 自定义HttpMessageConverter    @Bean     public MyMessageConverter converter(){        return new MyMessageConverter();    }}//InternalResourceViewResolver继承/实现直到ViewResolverpublic class InternalResourceViewResolver extends UrlBasedViewResolver {}public class UrlBasedViewResolver extends AbstractCachingViewResolver implements Ordered {}public abstract class AbstractCachingViewResolver extends WebApplicationObjectSupport implements ViewResolver {}public interface ViewResolver {    View resolveViewName(String viewName, Locale locale) throws Exception;}//源码中JstlView的继承/实现到Viewpublic class JstlView extends InternalResourceView {}public class InternalResourceView extends AbstractUrlBasedView {}public abstract class AbstractUrlBasedView extends AbstractView implements InitializingBean {}public abstract class AbstractView extends WebApplicationObjectSupport implements View, BeanNameAware {}public interface View {}

//1WebApplicationInitializer是Spring提供用来配置Servlet3.0+配置的接口,替代web.xml,实现此接口将会被自动被SpringServletContainerInitializer(用来启动Servlet3.0容器)获取到.public class WebInitializer implements WebApplicationInitializer {    @Override    public void onStartup(ServletContext servletContext)            throws ServletException {        AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();        ctx.register(MyMvcConfig.class);        ctx.setServletContext(servletContext); //2        Dynamic servlet = servletContext.addServlet("dispatcher", new DispatcherServlet(ctx)); //3        servlet.addMapping("/");        servlet.setLoadOnStartup(1);        servlet.setAsyncSupported(true);//1    }}//WebApplicationInitializer源码如下:public interface WebApplicationInitializer {    /**     * Configure the given {@link ServletContext} with any servlets, filters, listeners     * context-params and attributes necessary for initializing this web application. See     * examples {@linkplain WebApplicationInitializer above}.     * @param servletContext the {@code ServletContext} to initialize     * @throws ServletException if any call against the given {@code ServletContext}     * throws a {@code ServletException}     */    void onStartup(ServletContext servletContext) throws ServletException;}

4.3 Spring mvc常用注解

@EnableWebMvc 开启SpringMvc,及一些默认配置
@Controller 声明为一个控制器
@RequestMapping 配置URL和方法之间的映射,支持servlet的reqeust和response作为配置参数
@ResponseBody 支持将返回值放在response体内,ajax时返回数据而不是页面.
@RequestBody 允许request的参数放在reqeust体中,而不是直接链接在地址后面.此注解放置在参数前.
@PathVariable 用来接收参数,如/news/001,可接收001作为参数,此注解放置在参数前.
@RestController 组合注解,组合@Controller和ResponseBody.

//示例1@Controller // 1控制内@RequestMapping("/anno") //2映射路径public class DemoAnnoController {    @RequestMapping(produces = "text/plain;charset=UTF-8")  // 3定制返回类型和字符集    public @ResponseBody String index(HttpServletRequest request) { // 4接收request参数        return "url:" + request.getRequestURL() + " can access";    }    @RequestMapping(value = "/pathvar/{str}", produces = "text/plain;charset=UTF-8")// 5接收路径参数,用在restful风格    public @ResponseBody String demoPathVar(@PathVariable String str, //3            HttpServletRequest request) {        return "url:" + request.getRequestURL() + " can access,str: " + str;    }    @RequestMapping(value = "/requestParam", produces = "text/plain;charset=UTF-8") //6 接收url参数    public @ResponseBody String passRequestParam(Long id,            HttpServletRequest request) {        return "url:" + request.getRequestURL() + " can access,id: " + id;    }    @RequestMapping(value = "/obj", produces = "application/json;charset=UTF-8")//7 解释参数到对象    @ResponseBody //8  返回数据也不是页面    public String passObj(DemoObj obj, HttpServletRequest request) {         return "url:" + request.getRequestURL()                     + " can access, obj id: " + obj.getId()+" obj name:" + obj.getName();    }    @RequestMapping(value = { "/name1", "/name2" }, produces = "text/plain;charset=UTF-8")//9 支持name1和name2    public @ResponseBody String remove(HttpServletRequest request) {        return "url:" + request.getRequestURL() + " can access";    }}@RestController //1 rest的哦控制器@RequestMapping("/rest")public class DemoRestController {    @RequestMapping(value = "/getjson",            produces={"application/json;charset=UTF-8"}) //2 返回为json(application/json)    public DemoObj getjson (DemoObj obj){        return new DemoObj(obj.getId()+1, obj.getName()+"yy");//3 对象自动转成json    }    @RequestMapping(value = "/getxml",            produces={"application/xml;charset=UTF-8"})//4 返回为json(application/xml)    public DemoObj getxml(DemoObj obj){        return new DemoObj(obj.getId()+1, obj.getName()+"yy");//5对象自动转成xml    }}

4.4 Spring mvc高级配置

4.4.1 静态资源

详细查看4.2中的MyMvcConfig.java中的4.4.1介绍.

4.4.2 拦截器配置

Interceptor 拦截器.可让普通的Bean实现HandleInterceptor接口或者继承HandleInterceptorAdapter来实现自定义拦截器.
通过重写WebMvcConfigurerAdapter的addInterceptors方法来注册自定义的拦截器.

代码示例:
““
DemoInterceptor继承HandlerInterceptorAdapter,重写preHandle和postHandle
配合看4.2中的MyMvcConfig.java中的4.4.2一起使用.

public class DemoInterceptor extends HandlerInterceptorAdapter {//1继承

@Overridepublic boolean preHandle(HttpServletRequest request, //2在请求发生前执行        HttpServletResponse response, Object handler) throws Exception {    long startTime = System.currentTimeMillis();    request.setAttribute("startTime", startTime);    return true;}@Overridepublic void postHandle(HttpServletRequest request, //3在请求完成后执行        HttpServletResponse response, Object handler,        ModelAndView modelAndView) throws Exception {    long startTime = (Long) request.getAttribute("startTime");    request.removeAttribute("startTime");    long endTime = System.currentTimeMillis();    System.out.println("本次请求处理时间为:" + new Long(endTime - startTime)+"ms");    request.setAttribute("handlingTime", endTime - startTime);}

}

““

4.4.3 @ControllerAdvice

控制器建言(增强).可以对Controller参数/异常做controller执行前的处理.
@ControllerAdvice 将控制器的全局配置放置在同一个位置,注解了@ControllerAdvice的方法可用@ExceptionHandler,@InitBinder,@ModelAttribute注册到方法上,对所有注解了@RequestMapping的控制器内有效.
@ExceptionHandler :用于全局处理控制器里的异常. value属性设置可以过滤拦截的条件.
@InitBinder 用来设置WebDataBinder,WebDataBinder用来自动绑定前台请求参数到Model中. 比如设置将某个参数值置空.
@ModelAttribute 绑定键值对到Model里.

4.4.4 其它配置

1) ViewController

RequestMapping和return string的函数写法.
源码查看: 4.2 中的MyMvcConfig的 4.4.4-1

2) 路径匹配参数配置

设置路径参数中的.字符不被忽略.
源码查看: 4.2 中的MyMvcConfig的 4.4.4-2

更多配置,查看WebMvcConfigurerAdapter的API和WebMvcConfigurer

源码中:WebMvcConfigurerAdapter implements WebMvcConfigurer

4.5 Spring mvc的高级配置

4.5.1 文件上传

引入commons-fileupload和commons-io,查看4.2中的pom.xml
查看源码:/highlight_springmvc4/com.wisely.highlight_springmvc4.web.ch4_5.UploadController.java,和4.2中的MyMvcConfig的的4.5.1 文件上传.

4.5.2 自定义HttpMessageConverter

HttpMessageConverter 用来处理request和response里的数据.
内置了大量HttpMessageConverter: MappingJackson2HttpMessageConverter,StringHttpMessageConverter等.
示例可以自定义一种MediaType,然后MyMvcConfig中实现相关方法注册,然后自定义该类Message的处理方法.实现自动转换.

//com.wisely.highlight_springmvc4.messageconverter.MyMessageConverter.java及MyMvcConfig.java//highlight_springmvc4/src/main/resources/views/converter.jsp //highlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/web/ch4_5/ConverterController.java

4.5.3 服务器端推送技术

1)SSE

支持Chrome,FireFox等,EventSource是SSE的客户端,添加SSE客户端监听,然后到等待服务端推送消息.

//highlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/web/ch4_5/SseController.java//highlight_springmvc4/src/main/resources/views/sse.jsp

2)Servlet3.0+异步方法处理

DeferredResult.
步骤有:开启异步方法支持,打开计划配置,Service定义DeferredResult,计划任务定时为DeferredResult.

highlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/web/ch4_5/AysncController.javahighlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/service/PushService.javahighlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/WebInitializer.javahighlight_springmvc4/src/main/resources/views/async.jsp

4.6 Spring mvc测试

Servlet模拟对象 MockMVC,MockHttpServletRequest,MockHttpServletResponse,MockHttpSession.
JUnit和Spring TestContextFramework

/highlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/service/DemoService.java/highlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/web/ch4_6/NormalController.java/highlight_springmvc4/src/main/java/com/wisely/highlight_springmvc4/web/ch4_6/MyRestController.java/highlight_springmvc4/src/test/java/com/wisely/highlight_springmvc4/web/ch4_6/TestControllerIntegrationTests.java

5.Spring Boot基础

6.Spring Boot核心

7.Spring Boot的Web开发

8.Spring Boot的数据访问

9.Spring Boot的企业级开发

10.Spring Boot开发部署与测试

11.Spring 应用监控

Spring Boot有四大神器，分别是auto-configuration、starters、cli、actuator

12.分布式系统开发