SptringBoot第八讲(web开发第一讲)
看教程使用的是springboot1.5.x的版本，我是用的Spring2.0.x版本，静态资源映射关系我就不添加代码，添加了不看源码也找不到。最下面有关于自动化的链接，可以自己去官网看看
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
在访问的时候只需要写webjars下面资源的名称即可
<dependency>
<groupId>org.webjarsgroupId>
<artifactId>jqueryartifactId>
<version>3.3.1version>
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
SpringBoot推荐的Thymeleaf；
语法更简单，功能更强大；
1、引入thymeleaf；
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-thymeleafartifactId>
2.1.6
dependency>
切换thymeleaf版本
<properties>
<thymeleaf.version>3.0.9.RELEASEthymeleaf.version>
<thymeleaf-layout-dialect.version>2.2.2thymeleaf-layout-dialect.version>
properties>
2、Thymeleaf使用
@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
<html lang="en" xmlns:th="http://www.thymeleaf.org">
2、使用thymeleaf语法；
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>Titletitle>
head>
<body>
<h1>成功！h1>
<div th:text="${hello}">这是显示欢迎信息div>
body>
html>
3、语法规则
1）、th:text；改变当前元素里面的文本内容；
th：任意html属性；来替换原生属性的值
2）、表达式？
Simple expressions:（表达式语法）
Variable Expressions: ${...}：获取变量值；OGNL；
1）、获取对象的属性、调用方法
2）、使用内置的基本对象：
#ctx : the context object.
#vars: the context variables.
#locale : the context locale.
#request : (only in Web Contexts) the HttpServletRequest object.
#response : (only in Web Contexts) the HttpServletResponse object.
#session : (only in Web Contexts) the HttpSession object.
#servletContext : (only in Web Contexts) the ServletContext object.
${session.foo}
3）、内置的一些工具对象：
#execInfo : information about the template being processed.
#messages : methods for obtaining externalized messages inside variables expressions, in the same way as they would be obtained using #{…} syntax.
#uris : methods for escaping parts of URLs/URIs
#conversions : methods for executing the configured conversion service (if any).
#dates : methods for java.util.Date objects: formatting, component extraction, etc.
#calendars : analogous to #dates , but for java.util.Calendar objects.
#numbers : methods for formatting numeric objects.
#strings : methods for String objects: contains, startsWith, prepending/appending, etc.
#objects : methods for objects in general.
#bools : methods for boolean evaluation.
#arrays : methods for arrays.
#lists : methods for lists.
#sets : methods for sets.
#maps : methods for maps.
#aggregates : methods for creating aggregates on arrays or collections.
#ids : methods for dealing with id attributes that might be repeated (for example, as a result of an iteration).
Selection Variable Expressions: *{...}：选择表达式：和${}在功能上是一样；
补充：配合 th:object="${session.user}：
Name: Sebastian.
Surname: Pepper.
Nationality: Saturn.
Message Expressions: #{...}：获取国际化内容
Link URL Expressions: @{...}：定义URL；
@{/order/process(execId=${execId},execType='FAST')}
Fragment Expressions: ~{...}：片段引用表达式
...
Literals（字面量）
Text literals: 'one text' , 'Another one!' ,…
Number literals: 0 , 34 , 3.0 , 12.3 ,…
Boolean literals: true , false
Null literal: null
Literal tokens: one , sometext , main ,…
Text operations:（文本操作）
String concatenation: +
Literal substitutions: |The name is ${name}|
Arithmetic operations:（数学运算）
Binary operators: + , - , * , / , %
Minus sign (unary operator): -
Boolean operations:（布尔运算）
Binary operators: and , or
Boolean negation (unary operator): ! , not
Comparisons and equality:（比较运算）
Comparators: > , < , >= , <= ( gt , lt , ge , le )
Equality operators: == , != ( eq , ne )
Conditional operators:条件运算（三元运算符）
If-then: (if) ? (then)
If-then-else: (if) ? (then) : (else)
Default: (value) ?: (defaultvalue)
Special tokens:
No-Operation: _
4、SpringMVC自动配置
https://docs.spring.io/spring-boot/docs/1.5.10.RELEASE/reference/htmlsingle/#boot-features-developing-web-applications
27.1.1 Spring MVC auto-configuration（spring2.0.x）对应的官网自动化配置doc