SpringBoot系列之Thymeleaf语法简单介绍 [toc] Thymeleaf官方文档已经有比较详细的描述,所以本博客只挑部分比较重要的点看一下,还有介绍一下和SpringBoot怎么集成使用 ## 1、模板引擎 引用百度百科的模板引擎解释: > 模板引擎(这里特指用于Web开发的模板引擎)是为了使用户界面与业务数据(内容)分离而产生的,它可以生成特定格式的文档,用于网站的模板引擎就会生成一个标准的HTML文档。 在JavaEE领域有几中比较常用的模板引擎,分别是Jsp、Velocity、Freemarker、Thymeleaf,不过对于前端页面渲染效率来说,jsp其实还是最快的,Velocity次之。Thymeleaf虽然渲染效率不是很快,但是语法方面是比较轻巧的,Thymeleaf语法比Velocity轻巧,但是渲染效率不如Velocity ## 2、Thymeleaf简介 ### 2.1)、Thymeleaf定义 Thymeleaf是适用于Web和独立环境的现代服务器端Java模板引擎,能够处理HTML,XML,JavaScript,CSS甚至纯文本。具体参考[Thymeleaf官网](https://www.thymeleaf.org/documentation.html) 官网提供了在线文档也有文件格式的各种文档 ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191129195429596.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) ### 2.2)、适用模板 Thymeleaf适用于如下模板: * HTML * XML * TEXT * JAVASCRIPT * CSS * RAW 有两种标记模板模式(HTML 和 XML)、三种文本模板模式(TEXT、JAVASCRIPT 和 CSS)和一种无操作模板模式 (RAW)。 ok,下面给出一些比较重要的知识点 ## 3、重要知识点 ### 3.1)、th:text和th:utext 这是很常用的text标签,作用是Thymeleaf中设置文本的标签,分为两种,一种是th:text,另外一种是th:utext,两种最重要的区别就是会不会对特殊字符进行转义 * th:text:将所有特殊字符转成字符 * th:utext:不会将特殊字符进行字符转义 > 注意:这里的特殊字符主要指html标签,/n、/t、etc.这些字符是不支持的 写个例子对比一下: ```html <span th:text="${'Welcome to our <b>fantastic</b> grocery store!'}"></span><br/> <span th:utext="${'Welcome to our <b>fantastic</b> grocery store!'}"></span> ``` ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130133628779.png) ### 3.2)、标准表达式 官方文档里有standard Expression Syntax这个章节,介绍的就是标准的表达式语法应用 * Simple expressions(简单表达式语法): * Variable Expressions: ${...} // 获取遍历值,支持OGNL语法 etc. 1. 获取自定义对象的属性值 2. 获取自定义的变量属性值 3. 使用内置的基本对象 * #ctx: the context object. * #vars: the context variables. * #locale: the context locale. * #request: (only in Web Contexts) the HttpServletRequest object. * #response: (only in Web Contexts) the HttpServletResponse object. * #session: (only in Web Contexts) the HttpSession object. * #servletContext: (only in Web Contexts) the ServletContext object. 详情参考[Thymeleaf的附录A](https://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html#appendix-a-expression-basic-objects) 4. 内置的工具类对象 官网已经给出比较详细的介绍,详细用法参考[Thymeleaf附录B](https://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html#appendix-b-expression-utility-objects) ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130141251923.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) * Selection Variable Expressions: *{...} // 选定对象,也就是获取使用 th:object 属性的表达式的值 * Message Expressions: #{...} //国际化内容 详细用法参考我的博客:[ SpringBoot系列之i18n国际化多语言支持教程](https://smilenicky.blog.csdn.net/article/details/103226530) * Link URL Expressions: @{...} // 定义URL链接 ```html <link th:href="@{/static/css/public.css}" rel="stylesheet" type="text/css" /> <link th:href="@{/static/css/index.css}" rel="stylesheet" type="text/css" /> <script type="text/javascript" th:src="@{/static/js/jquery-1.3.2.min.js}"></script> <script type="text/javascript" th:src="@{/static/js/html5.js}"></script> <script type="text/javascript" th:src="@{/static/js/popbox.js}"></script> ``` * Fragment Expressions: ~{...} //片段引用的表达式 eg: `<div th:insert="~{commons :: main}">....</div>` * Literals (字面量值) * Text literals: 'one text', 'Another one!',… * Number literals: 0, 34, 3.0, 12.3,… * Boolean literals: true, false * Null literal: null * Literal tokens: one, sometext, main,… * Text operations (文本操作): * String concatenation: + //连接操作 `@{url/}+${id}` * Literal substitutions: |The name is ${name}| //字符串中使用` ${name}`变量值 * Arithmetic operations: (数学运算) * Binary operators: +, -, *, /, % * Minus sign (unary operator): - * Boolean operations:(布尔运算) * Binary operators: and, or * Boolean negation (unary operator): !, not * Comparisons and equality:(比较运算) * Comparators: >, <, >=, <= (gt, lt, ge, le) * Equality operators: ==, != (eq, ne) * Conditional operators:(条件运算,包括三元运算符etc.) * If-then: (if) ? (then) * If-then-else: (if) ? (then) : (else) * Default: (value) ?: (defaultvalue) * Special tokens:(特殊的令牌,也就是使用No-Operatio) * No-Operation: _ ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130143327119.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) > All these features can be combined and neste: > `'User is of type ' + (${user.isAdmin()} ? 'Administrator' : (${user.type} ?: 'Unknown'))` 翻译过来意思是,这些语法都可以组合使用,这个章节是Thymeleaf一个重要的基本使用章节,本博客对一些重要的知识点进行摘录同时介绍一下在SpringBoot里如何使用,当然自然没有[官方文档](https://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html)详细的,不过官方并没有通过中文文档,英文水平不好的话,阅读起来比较困难,当然我也找了一篇国内翻译过来的[Thymeleaf中文文档](https://fanlychie.github.io/post/thymeleaf.html),读者详细的可以参考文档 ### 3.3)、Thymeleaf遍历 遍历是Thymeleaf很常用的例子,支持的属性值有: ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130151207704.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) 下面还是给下例子,比较容易理解,如下代码使用th:each,`th:each="item : ${items}"` ```html <!--最新上架--> <div class="first-pannel clearfix"> <div class="index-f clearfix"> <h3 class="index-f-head"> 最新上架 <span>每天都有上新,每天都有惊喜</span> </h3> <div class="index-f-body"> <div class="top-sales newProduct"> <ul class="top-sales-list clearfix"> <li class="top-sales-item newProduct" th:each="item : ${items}"> <p class="item-img"> <a th:href="@{'/portal/item/toDetail/'+${item.spuId}+'/'+${item.skuId}}"><img th:src="@{${item.imgPath}}" /></a> </p> <p class="item-buss"><a th:href="@{'/portal/item/toDetail/'+${item.spuId}+'/'+${item.skuId}}"></a></p> <p class="item-name spec"><a th:href="@{'/portal/item/toDetail/'+${item.spuId}+'/'+${item.skuId}}" th:text="${item.itemName}"></a></p> <p class="item-price spec"><em th:text="${item.mPrice}"></em>元</p> </li> </ul> </div> </div> </div> </div> <!--最新上架//--> ``` ### 3.4)、公共模块抽取 在项目开发中经常遇到一些可以重用的页面,这时候就可以Thymeleaf的Template Layout进行公共页面的复用 本博客以官方介绍的复用footer.html页面进行说明 ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130152413599.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) 使用步骤: 1. 抽取公共的片段 ```html <!DOCTYPE html> <html xmlns:th="http://www.thymeleaf.org"> <body> <div th:fragment="copy"> &copy; 2011 The Good Thymes Virtual Grocery </div> </body> </html> ``` 2. 引入公共的片段 `<div th:insert="~{footer :: copy}"></div>` ~{templatename::selector}:模板名::选择器 ~{templatename::fragmentname}:模板名::片段名 ```bash <div th:insert="footer :: copy"></div> <div th:replace="footer :: copy"></div> <div th:include="footer :: copy"></div ``` 三种引入公共片段的th属性: * th:insert:将公共片段整个插入到声明引入的元素中 * th:replace:将声明引入的元素替换为公共片段 * th:include:将被引入的片段的内容包含进这个标签中 效果对比: ```html <div> <footer> &copy; 2011 The Good Thymes Virtual Grocery </footer> </div> <footer> &copy; 2011 The Good Thymes Virtual Grocery </footer> <div> &copy; 2011 The Good Thymes Virtual Grocery </div ``` ### 3.5)、行内写法介绍 所谓行内写法就是没写在html对应的标签里的写法,直接在页面空白处,用[[....]]或者[(....)]的写法,然后[[....]]和[(....)]的区别其实就等同于th:text和th:utext的区别,一个会进行转义,一个不会转义特殊字符 * [[....]]写法:会转义html标签这些特殊字符(转成字符) * [(....)]写法:不会转义html标签这些特殊字符(按照其原意) 写个例子就明白了: ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130173928712.png) ```html <span> The message is [[${msg}]] </span> <br/> <span> The message is [(${msg})] </span> ``` ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130174019738.png) ### 3.6)、Thymeleaf语法规则 引用尚桂谷老师的归纳: ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130174139739.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) ## 4、SpringBoot集成 ### 4.1)、Springboot集成Thymeleaf简介 **maven配置** 因为引入了SpringBoot的parent工程,所以不需要写版本号 ``` <!-- Themeleaf --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency> ``` **application.yml配置** 注意:这里的属性大部分都可以不配置的,因为Springboot的自动配置因为做了很多自动配置,我们不配置,就使用默认的,不过下面的例子只是给读者了解一下有这些配置 ```yaml #添加Thymeleaf配置,除了cache在项目没上线前建议关了,其它配置都可以不用配的,本博客只是列举一下有这些配置 thymeleaf: # cache默认开启的,这里可以关了,项目上线之前,项目上线后可以开启 cache: false # 这个prefix可以注释,因为默认就是templates的,您可以改成其它的自定义路径 prefix: classpath:/templates/ suffix: .html mode: HTML5 # 指定一下编码为utf8 encoding: UTF-8 # context-type为text/html,也可以不指定,因为boot可以自动识别 content-type: text/html ``` ok,Springboot中Thymeleaf使用非常简单,因为Springboot已经为我们做了很多自动配置,其实,yaml都不需要配置的,直接引入对应的jar,然后就可以直接使用,在resources资源文件夹下面新建一个templates文件夹,所有的html文件都丢在这里,静态资源文件也丢在resources资源文件夹下面 新建一个html文件,然后注意加上`<html xmlns:th="http://www.thymeleaf.org">` 注意Thymeleaf语法要求比较严格 `<meta charset="utf-8" >`,不如这样写是不可以的,必须加上斜杠的,`<meta charset="utf-8" />` ```html <!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <div> <span th:text="${'Welcome to our <b>fantastic</b> grocery store!'}"></span><br/> <span th:utext="${'Welcome to our <b>fantastic</b> grocery store!'}"></span> </div> <span> The message is [[${msg}]] </span> <br/> <span> The message is [(${msg})] </span> </body> </html> ``` ### 4.2)、Thymeleaf自动配置源码简单分析 ok,然后为什么我说直接引入对应pom配置就可以直接使用了?因为Springboot已经为项目做了很多自动配置,所以本博客简单跟一下源码,了解一下SpringbootThymeleaf的自动配置 SpringBoot的自动配置类在ThymeleafAutoConfiguration里 ```java package org.springframework.boot.autoconfigure.thymeleaf; .... @Configuration(proxyBeanMethods = false)//定义这是一个配置类 @EnableConfigurationProperties(ThymeleafProperties.class)//使用ThymeleafProperties属性类的属性 @ConditionalOnClass({ TemplateMode.class, SpringTemplateEngine.class })//指定TemplateMode、SpringTemplateEngine(模板引擎类)起效的情况,整个配置类才起作用 @AutoConfigureAfter({ WebMvcAutoConfiguration.class, WebFluxAutoConfiguration.class })//必须在WebMvcAutoConfiguration(SpringMVC自动配置类,这个配置类会加载组装所有的视图解析器)、WebFluxAutoConfiguration类起效后,这个Thymeleaf自动配置类才起效 public class ThymeleafAutoConfiguration { //没有自定义的模板解析器类的情况,使用默认的模板解析器 @Configuration(proxyBeanMethods = false) @ConditionalOnMissingBean(name = "defaultTemplateResolver") static class DefaultTemplateResolverConfiguration { private static final Log logger = LogFactory.getLog(DefaultTemplateResolverConfiguration.class); //Thymeleaf的properties配置 private final ThymeleafProperties properties; private final ApplicationContext applicationContext; DefaultTemplateResolverConfiguration(ThymeleafProperties properties, ApplicationContext applicationContext) { this.properties = properties; this.applicationContext = applicationContext; } //用PostConstruct注解,在依赖注入完成之后,实现类的初始化配置,这个方法主要是检查模板引擎的资源文件路径是否有 @PostConstruct void checkTemplateLocationExists() { boolean checkTemplateLocation = this.properties.isCheckTemplateLocation(); if (checkTemplateLocation) { TemplateLocation location = new TemplateLocation(this.properties.getPrefix()); if (!location.exists(this.applicationContext)) { logger.warn("Cannot find template location: " + location + " (please add some templates or check " + "your Thymeleaf configuration)"); } } } //默认的Thymeleaf资源解析器 @Bean SpringResourceTemplateResolver defaultTemplateResolver() { SpringResourceTemplateResolver resolver = new SpringResourceTemplateResolver(); //资源解析器的所有配置 resolver.setApplicationContext(this.applicationContext); resolver.setPrefix(this.properties.getPrefix()); resolver.setSuffix(this.properties.getSuffix()); resolver.setTemplateMode(this.properties.getMode()); if (this.properties.getEncoding() != null) { resolver.setCharacterEncoding(this.properties.getEncoding().name()); } resolver.setCacheable(this.properties.isCache()); Integer order = this.properties.getTemplateResolverOrder(); if (order != null) { resolver.setOrder(order); } resolver.setCheckExistence(this.properties.isCheckTemplate()); return resolver; } } //又是Thymeleaf的自动配置,自动配置模板引擎SpringTemplateEngine @Configuration(proxyBeanMethods = false) protected static class ThymeleafDefaultConfiguration { @Bean @ConditionalOnMissingBean(ISpringTemplateEngine.class) SpringTemplateEngine templateEngine(ThymeleafProperties properties, ObjectProvider<ITemplateResolver> templateResolvers, ObjectProvider<IDialect> dialects) { SpringTemplateEngine engine = new SpringTemplateEngine(); engine.setEnableSpringELCompiler(properties.isEnableSpringElCompiler()); engine.setRenderHiddenMarkersBeforeCheckboxes(properties.isRenderHiddenMarkersBeforeCheckboxes()); templateResolvers.orderedStream().forEach(engine::addTemplateResolver); dialects.orderedStream().forEach(engine::addDialect); return engine; } } @Configuration(proxyBeanMethods = false) @ConditionalOnWebApplication(type = Type.SERVLET) @ConditionalOnProperty(name = "spring.thymeleaf.enabled", matchIfMissing = true) static class ThymeleafWebMvcConfiguration { @Bean @ConditionalOnEnabledResourceChain @ConditionalOnMissingFilterBean(ResourceUrlEncodingFilter.class) FilterRegistrationBean<ResourceUrlEncodingFilter> resourceUrlEncodingFilter() { FilterRegistrationBean<ResourceUrlEncodingFilter> registration = new FilterRegistrationBean<>( new ResourceUrlEncodingFilter()); registration.setDispatcherTypes(DispatcherType.REQUEST, DispatcherType.ERROR); return registration; } //比较重要的视图解析器配置 @Configuration(proxyBeanMethods = false) static class ThymeleafViewResolverConfiguration { @Bean @ConditionalOnMissingBean(name = "thymeleafViewResolver") ThymeleafViewResolver thymeleafViewResolver(ThymeleafProperties properties, SpringTemplateEngine templateEngine) { ThymeleafViewResolver resolver = new ThymeleafViewResolver(); //设置模板引擎 resolver.setTemplateEngine(templateEngine); //字符编码设置 resolver.setCharacterEncoding(properties.getEncoding().name()); resolver.setContentType( appendCharset(properties.getServlet().getContentType(), resolver.getCharacterEncoding())); resolver.setProducePartialOutputWhileProcessing( properties.getServlet().isProducePartialOutputWhileProcessing()); resolver.setExcludedViewNames(properties.getExcludedViewNames()); resolver.setViewNames(properties.getViewNames()); // This resolver acts as a fallback resolver (e.g. like a // InternalResourceViewResolver) so it needs to have low precedence resolver.setOrder(Ordered.LOWEST_PRECEDENCE - 5); //Thymeleaf缓存 resolver.setCache(properties.isCache()); return resolver; } private String appendCharset(MimeType type, String charset) { if (type.getCharset() != null) { return type.toString(); } LinkedHashMap<String, String> parameters = new LinkedHashMap<>(); parameters.put("charset", charset); parameters.putAll(type.getParameters()); return new MimeType(type, parameters).toString(); } } } @Configuration(proxyBeanMethods = false) @ConditionalOnWebApplication(type = Type.REACTIVE) @ConditionalOnProperty(name = "spring.thymeleaf.enabled", matchIfMissing = true) static class ThymeleafReactiveConfiguration { @Bean @ConditionalOnMissingBean(ISpringWebFluxTemplateEngine.class) SpringWebFluxTemplateEngine templateEngine(ThymeleafProperties properties, ObjectProvider<ITemplateResolver> templateResolvers, ObjectProvider<IDialect> dialects) { SpringWebFluxTemplateEngine engine = new SpringWebFluxTemplateEngine(); engine.setEnableSpringELCompiler(properties.isEnableSpringElCompiler()); engine.setRenderHiddenMarkersBeforeCheckboxes(properties.isRenderHiddenMarkersBeforeCheckboxes()); templateResolvers.orderedStream().forEach(engine::addTemplateResolver); dialects.orderedStream().forEach(engine::addDialect); return engine; } } //ThymeleafWebFluxConfiguration自动配置 @Configuration(proxyBeanMethods = false) @ConditionalOnWebApplication(type = Type.REACTIVE) @ConditionalOnProperty(name = "spring.thymeleaf.enabled", matchIfMissing = true) static class ThymeleafWebFluxConfiguration { @Bean @ConditionalOnMissingBean(name = "thymeleafReactiveViewResolver") ThymeleafReactiveViewResolver thymeleafViewResolver(ISpringWebFluxTemplateEngine templateEngine, ThymeleafProperties properties) { ThymeleafReactiveViewResolver resolver = new ThymeleafReactiveViewResolver(); resolver.setTemplateEngine(templateEngine); mapProperties(properties, resolver); mapReactiveProperties(properties.getReactive(), resolver); // This resolver acts as a fallback resolver (e.g. like a // InternalResourceViewResolver) so it needs to have low precedence resolver.setOrder(Ordered.LOWEST_PRECEDENCE - 5); return resolver; } private void mapProperties(ThymeleafProperties properties, ThymeleafReactiveViewResolver resolver) { PropertyMapper map = PropertyMapper.get(); map.from(properties::getEncoding).to(resolver::setDefaultCharset); resolver.setExcludedViewNames(properties.getExcludedViewNames()); resolver.setViewNames(properties.getViewNames()); } private void mapReactiveProperties(Reactive properties, ThymeleafReactiveViewResolver resolver) { PropertyMapper map = PropertyMapper.get(); map.from(properties::getMediaTypes).whenNonNull().to(resolver::setSupportedMediaTypes); map.from(properties::getMaxChunkSize).asInt(DataSize::toBytes).when((size) -> size > 0) .to(resolver::setResponseMaxChunkSizeBytes); map.from(properties::getFullModeViewNames).to(resolver::setFullModeViewNames); map.from(properties::getChunkedModeViewNames).to(resolver::setChunkedModeViewNames); } } @Configuration(proxyBeanMethods = false) @ConditionalOnClass(LayoutDialect.class) static class ThymeleafWebLayoutConfiguration { @Bean @ConditionalOnMissingBean LayoutDialect layoutDialect() { return new LayoutDialect(); } } @Configuration(proxyBeanMethods = false) @ConditionalOnClass(DataAttributeDialect.class) static class DataAttributeDialectConfiguration { @Bean @ConditionalOnMissingBean DataAttributeDialect dialect() { return new DataAttributeDialect(); } } @Configuration(proxyBeanMethods = false) @ConditionalOnClass({ SpringSecurityDialect.class }) static class ThymeleafSecurityDialectConfiguration { @Bean @ConditionalOnMissingBean SpringSecurityDialect securityDialect() { return new SpringSecurityDialect(); } } @Configuration(proxyBeanMethods = false) @ConditionalOnClass(Java8TimeDialect.class) static class ThymeleafJava8TimeDialect { @Bean @ConditionalOnMissingBean Java8TimeDialect java8TimeDialect() { return new Java8TimeDialect(); } } } ``` ThymeleafProperties是SpringBoot的属性配置类,使用ConfigurationProperties注解进行属性映射 ```java @ConfigurationProperties(prefix = "spring.thymeleaf") public class ThymeleafProperties { private static final Charset DEFAULT_ENCODING = StandardCharsets.UTF_8; //默认的模板资源路径 public static final String DEFAULT_PREFIX = "classpath:/templates/"; //默认解析html资源 public static final String DEFAULT_SUFFIX = ".html"; /** * Whether to check that the template exists before rendering it. */ private boolean checkTemplate = true; /** * Whether to check that the templates location exists. */ private boolean checkTemplateLocation = true; /** * Prefix that gets prepended to view names when building a URL. */ private String prefix = DEFAULT_PREFIX; /** * Suffix that gets appended to view names when building a URL. */ private String suffix = DEFAULT_SUFFIX; /** * Template mode to be applied to templates. See also Thymeleaf's TemplateMode enum. */ //默认模式也是html的 private String mode = "HTML"; /** * Template files encoding. */ private Charset encoding = DEFAULT_ENCODING; /** * Whether to enable template caching. */ //默认开启缓存,项目没上线建议通过配置关闭,然后按F9就可以自动编译,避免影响调试 private boolean cache = true; .... } ``` ok,然后简单跟一下视图解析器的源码:Thymeleaf视图解析器类的关键代码,创建视图view的方法,如图,也是根据viewname进行重定向 ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130202942288.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) 从上面方法可以看出进行重定向或者forward等等方法,然后调一下redirect的,看看RedirectView类,翻下源码,找到如下关键代码: ![在这里插入图片描述](https://img-blog.csdnimg.cn/201911302032260.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) 同样在这个类里,进行了状态码设置,请求头设置,然后response.sendRedirect(encodedURL); ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130203441106.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) 而forward的是通过如图方法进行页面跳转: ![在这里插入图片描述](https://img-blog.csdnimg.cn/20191130203659218.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9zbWlsZW5pY2t5LmJsb2cuY3Nkbi5uZXQ=,size_16,color_FFFFFF,t_70) 附录: [Thymeleaf官方例子](https://github.com/thymeleaf/thymeleafexamples-gtvg)