## 1、简介
使用SpringBoot;
**1)、创建SpringBoot应用,选中我们需要的模块;**
**2)、SpringBoot已经默认将这些场景配置好了,只需要在配置文件中指定少量配置就可以运行起来**
**3)、自己编写业务代码;**
**自动配置原理?**
这个场景SpringBoot帮我们配置了什么?能不能修改?能修改哪些配置?能不能扩展?xxx
```
xxxxAutoConfiguration:帮我们给容器中自动配置组件;
xxxxProperties:配置类来封装配置文件的内容;
```
## 2、SpringBoot对静态资源的映射规则;
```java
@ConfigurationProperties(prefix = "spring.resources", ignoreUnknownFields = false)
public class ResourceProperties implements ResourceLoaderAware {
//可以设置和静态资源有关的参数,缓存时间等
```
```java
WebMvcAuotConfiguration:
@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
if (!this.resourceProperties.isAddMappings()) {
logger.debug("Default resource handling disabled");
return;
}
Integer cachePeriod = this.resourceProperties.getCachePeriod();
if (!registry.hasMappingForPattern("/webjars/**")) {
customizeResourceHandlerRegistration(
registry.addResourceHandler("/webjars/**")
.addResourceLocations(
"classpath:/META-INF/resources/webjars/")
.setCachePeriod(cachePeriod));
}
String staticPathPattern = this.mvcProperties.getStaticPathPattern();
//静态资源文件夹映射
if (!registry.hasMappingForPattern(staticPathPattern)) {
customizeResourceHandlerRegistration(
registry.addResourceHandler(staticPathPattern)
.addResourceLocations(
this.resourceProperties.getStaticLocations())
.setCachePeriod(cachePeriod));
}
}
//配置欢迎页映射
@Bean
public WelcomePageHandlerMapping welcomePageHandlerMapping(
ResourceProperties resourceProperties) {
return new WelcomePageHandlerMapping(resourceProperties.getWelcomePage(),
this.mvcProperties.getStaticPathPattern());
}
//配置喜欢的图标
@Configuration
@ConditionalOnProperty(value = "spring.mvc.favicon.enabled", matchIfMissing = true)
public static class FaviconConfiguration {
private final ResourceProperties resourceProperties;
public FaviconConfiguration(ResourceProperties resourceProperties) {
this.resourceProperties = resourceProperties;
}
@Bean
public SimpleUrlHandlerMapping faviconHandlerMapping() {
SimpleUrlHandlerMapping mapping = new SimpleUrlHandlerMapping();
mapping.setOrder(Ordered.HIGHEST_PRECEDENCE + 1);
//所有 **/favicon.ico
mapping.setUrlMap(Collections.singletonMap("**/favicon.ico",
faviconRequestHandler()));
return mapping;
}
@Bean
public ResourceHttpRequestHandler faviconRequestHandler() {
ResourceHttpRequestHandler requestHandler = new ResourceHttpRequestHandler();
requestHandler
.setLocations(this.resourceProperties.getFaviconLocations());
return requestHandler;
}
}
```
==1)、所有 /webjars/** ,都去 classpath:/META-INF/resources/webjars/ 找资源;==
webjars:以jar包的方式引入静态资源;
http://www.webjars.org/
localhost:8080/webjars/jquery/3.3.1/jquery.js
```xml
<!--引入jquery-webjar-->在访问的时候只需要写webjars下面资源的名称即可
<dependency>
<groupId>org.webjars</groupId>
<artifactId>jquery</artifactId>
<version>3.3.1</version>
</dependency>
```
==2)、"/**" 访问当前项目的任何资源,都去(静态资源的文件夹)找映射==
```
"classpath:/META-INF/resources/",
"classpath:/resources/",
"classpath:/static/",
"classpath:/public/"
"/":当前项目的根路径
```
localhost:8080/abc === 去静态资源文件夹里面找abc
==3)、欢迎页; 静态资源文件夹下的所有index.html页面;被"/**"映射;==
localhost:8080/ 找index页面
==4)、所有的 **/favicon.ico 都是在静态资源文件下找;==
## 3、模板引擎
JSP、Velocity、Freemarker、Thymeleaf
![](images/template-engine.png)
SpringBoot推荐的Thymeleaf;
语法更简单,功能更强大;
### 1、引入thymeleaf;
```xml
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
2.1.6
</dependency>
切换thymeleaf版本
<properties>
<thymeleaf.version>3.0.9.RELEASE</thymeleaf.version>
<!-- 布局功能的支持程序 thymeleaf3主程序 layout2以上版本 -->
<!-- thymeleaf2 layout1-->
<thymeleaf-layout-dialect.version>2.2.2</thymeleaf-layout-dialect.version>
</properties>
```
### 2、Thymeleaf使用
```java
@ConfigurationProperties(prefix = "spring.thymeleaf")
public class ThymeleafProperties {
private static final Charset DEFAULT_ENCODING = Charset.forName("UTF-8");
private static final MimeType DEFAULT_CONTENT_TYPE = MimeType.valueOf("text/html");
public static final String DEFAULT_PREFIX = "classpath:/templates/";
public static final String DEFAULT_SUFFIX = ".html";
//
```
只要我们把HTML页面放在classpath:/templates/,thymeleaf就能自动渲染;
使用:
1、导入thymeleaf的名称空间
```xml
<html lang="en" xmlns:th="http://www.thymeleaf.org">
```
2、使用thymeleaf语法;
```html
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h1>成功!</h1>
<!--th:text 将div里面的文本内容设置为 -->
<div th:text="${hello}">这是显示欢迎信息</div>
</body>
</html>