1浊闪、簡(jiǎn)介
使用SpringBoot恼布；
1）、創(chuàng)建SpringBoot應(yīng)用搁宾，選中我們需要的模塊折汞；
2）、SpringBoot已經(jīng)默認(rèn)將這些場(chǎng)景配置好了盖腿，只需要在配置文件中指定少量配置就可以運(yùn)行起來(lái)
3）爽待、自己編寫業(yè)務(wù)代碼；
自動(dòng)配置原理翩腐？
這個(gè)場(chǎng)景SpringBoot幫我們配置了什么鸟款？能不能修改？能修改哪些配置茂卦？能不能擴(kuò)展何什？xxx
xxxxAutoConfiguration：幫我們給容器中自動(dòng)配置組件；
xxxxProperties:配置類來(lái)封裝配置文件的內(nèi)容等龙；
2处渣、SpringBoot對(duì)靜態(tài)資源的映射規(guī)則；
@ConfigurationProperties(prefix = "spring.resources", ignoreUnknownFields = false)
public class ResourceProperties implements ResourceLoaderAware {
//可以設(shè)置和靜態(tài)資源有關(guān)的參數(shù)蛛砰，緩存時(shí)間等
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();
//靜態(tài)資源文件夾映射
if (!registry.hasMappingForPattern(staticPathPattern)) {
customizeResourceHandlerRegistration(
registry.addResourceHandler(staticPathPattern)
.addResourceLocations(
this.resourceProperties.getStaticLocations())
.setCachePeriod(cachePeriod));
}
}
//配置歡迎頁(yè)映射
@Bean
public WelcomePageHandlerMapping welcomePageHandlerMapping(
ResourceProperties resourceProperties) {
return new WelcomePageHandlerMapping(resourceProperties.getWelcomePage(),
this.mvcProperties.getStaticPathPattern());
}
//配置喜歡的圖標(biāo)
@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）霍比、所有 /webjars/** ，都去 classpath:/META-INF/resources/webjars/ 找資源暴备；==
? webjars：以jar包的方式引入靜態(tài)資源；
image.png
pom文件里面引入：
<dependency>
<groupId>org.webjars</groupId>
<artifactId>jquery</artifactId>
<version>3.2.1</version>
</dependency>
==2）们豌、"/**" 訪問(wèn)當(dāng)前項(xiàng)目的任何資源涯捻，都去（靜態(tài)資源的文件夾）找映射==
"classpath:/META-INF/resources/",
"classpath:/resources/",
"classpath:/static/",
"classpath:/public/"
"/"：當(dāng)前項(xiàng)目的根路徑
localhost:8080/abc === 去靜態(tài)資源文件夾里面找abc
==3）、歡迎頁(yè)望迎； 靜態(tài)資源文件夾下的所有index.html頁(yè)面障癌；被"/**"映射；==
? localhost:8080/ 找index頁(yè)面
==4）辩尊、所有的 **/favicon.ico 都是在靜態(tài)資源文件下找涛浙；==
3、模板引擎
JSP摄欲、Velocity轿亮、Freemarker、Thymeleaf
image.png
SpringBoot推薦的Thymeleaf胸墙；
語(yǔ)法更簡(jiǎn)單我注，功能更強(qiáng)大；
1迟隅、引入thymeleaf但骨；
<!--引入thymeleaf模板引擎-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
2励七、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";
//
只要我們把HTML頁(yè)面放在classpath:/templates/，thymeleaf就能自動(dòng)渲染奔缠；
例如我寫一個(gè)測(cè)試類：
/**
* 該處返回 "success"返回的是 resources/templates目錄下面的頁(yè)面
* 該出要返回的是頁(yè)面掠抬，所以不能配置@ResponseBody注解，如果配置了該注解會(huì)以字符串直接輸出"success"
* @return success.html
*/
@RequestMapping("/success")
public String success(){
return "success";
}
然后 resources/templates目錄下新建success.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h1>跳轉(zhuǎn)成功頁(yè)面</h1>
</body>
</html>
image.png
使用：
1校哎、導(dǎo)入thymeleaf的名稱空間
<html lang="en" xmlns:th="http://www.thymeleaf.org">
2两波、使用thymeleaf語(yǔ)法；
后端代碼改寫成：
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h1>成功贬蛙！</h1>
<!--th:text 將div里面的文本內(nèi)容設(shè)置為 -->
<div th:text="${hello}">這是顯示歡迎信息</div>
</body>
</html>
image.png
3雨女、語(yǔ)法規(guī)則
1）、th:text阳准；改變當(dāng)前元素里面的文本內(nèi)容氛堕；
? th：任意html屬性；來(lái)替換原生屬性的值
image.png
2）野蝇、表達(dá)式讼稚？
Simple expressions:（表達(dá)式語(yǔ)法）
Variable Expressions: ${...}：獲取變量值；OGNL绕沈；
1）锐想、獲取對(duì)象的屬性、調(diào)用方法
2）乍狐、使用內(nèi)置的基本對(duì)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.
${session.foo}
3）赠摇、內(nèi)置的一些工具對(duì)象：
#execInfo : information about the template being processed.
#messages : methods for obtaining externalized messages inside variables expressions, in the same way as they would be obtained using #{…} syntax.
#uris : methods for escaping parts of URLs/URIs
#conversions : methods for executing the configured conversion service (if any).
#dates : methods for java.util.Date objects: formatting, component extraction, etc.
#calendars : analogous to #dates , but for java.util.Calendar objects.
#numbers : methods for formatting numeric objects.
#strings : methods for String objects: contains, startsWith, prepending/appending, etc.
#objects : methods for objects in general.
#bools : methods for boolean evaluation.
#arrays : methods for arrays.
#lists : methods for lists.
#sets : methods for sets.
#maps : methods for maps.
#aggregates : methods for creating aggregates on arrays or collections.
#ids : methods for dealing with id attributes that might be repeated (for example, as a result of an iteration).
Selection Variable Expressions: *{...}：選擇表達(dá)式：和${}在功能上是一樣；
補(bǔ)充：配合 th:object="${session.user}：
<div th:object="${session.user}">
<p>Name: <span th:text="*{firstName}">Sebastian</span>.</p>
<p>Surname: <span th:text="*{lastName}">Pepper</span>.</p>
<p>Nationality: <span th:text="*{nationality}">Saturn</span>.</p>
</div>
Message Expressions: #{...}：獲取國(guó)際化內(nèi)容
Link URL Expressions: @{...}：定義URL浅蚪；
@{/order/process(execId=${execId},execType='FAST')}
Fragment Expressions: ~{...}：片段引用表達(dá)式
<div th:insert="~{commons :: main}">...</div>
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 ${name}|
Arithmetic operations:（數(shù)學(xué)運(yùn)算）
Binary operators: + , - , * , / , %
Minus sign (unary operator): -
Boolean operations:（布爾運(yùn)算）
Binary operators: and , or
Boolean negation (unary operator): ! , not
Comparisons and equality:（比較運(yùn)算）
Comparators: > , < , >= , <= ( gt , lt , ge , le )
Equality operators: == , != ( eq , ne )
Conditional operators:條件運(yùn)算（三元運(yùn)算符）
If-then: (if) ? (then)
If-then-else: (if) ? (then) : (else)
Default: (value) ?: (defaultvalue)
Special tokens:
No-Operation: _
數(shù)據(jù)渲染到頁(yè)面相關(guān)用法：
html頁(yè)面：
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h1>跳轉(zhuǎn)成功頁(yè)面</h1>
<div th:text="${hello}"></div>
<hr/>
<div th:text="${hello}"></div>
<div th:utext="${hello}"></div>
<hr/>
<h4 th:text="${user}" th:each="user:${users}"></h4>
<hr/>
<h4>
<span th:each="user:${users}" > [[${user}]] </span>
</h4>
</body>
</html>
后端代碼：
@RequestMapping("/success")
public String success(Map<String,Object> map){
map.put("hello","你好");
map.put("users", Arrays.asList("張三","李四","王五"));
return "success";
}
效果圖：
image.png
