springMVC java配置文件 配置使用 thymeleaf 的时候一直报 这个错：
The type org.thymeleaf.ITemplateEngine cannot be resolved. It is indirectly referenced from required .class files
还以为是 引用的JRE版本太低或者太高 试了很久也没用，后来发现是由于 缺少jar包引起的
缺少：thymeleaf-3.0.3.RELEASE， 使用thymeleaf 需要thymeleaf-3.0.3.RELEASE 和thymeleaf-spring4-3.0.3.RELEASE.jar 两个jar包
可见：不只classNotFound 错误是可能缺少jar包，错误引用也可能是缺少jar包
看spring4 in action 根本没说需要什么bean，碰了很多钉子 最终得出 需要的thyleaf jar 包为：
thymeleaf-3.0.3.RELEASE 、thymeleaf-spring4-3.0.3.RELEASE.jar、attoparser-2.0.0.RELEASE.jar、unbescape-1.0.jar
mvc java 配置代码：
package config; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Configuration; import org.springframework.web.context.ContextLoader; import org.springframework.web.context.WebApplicationContext; import org.springframework.web.servlet.ViewResolver; import org.springframework.web.servlet.config.annotation.EnableWebMvc; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; import org.thymeleaf.TemplateEngine; import org.thymeleaf.spring4.SpringTemplateEngine; import org.thymeleaf.spring4.templateresolver.SpringResourceTemplateResolver; import org.thymeleaf.spring4.view.ThymeleafViewResolver; import org.thymeleaf.templatemode.TemplateMode; import org.thymeleaf.templateresolver.ITemplateResolver; import org.thymeleaf.templateresolver.ServletContextTemplateResolver; @EnableWebMvc @ComponentScan(basePackages="controller") @Configuration public class MvcConfig extends WebMvcConfigurerAdapter { @Bean public ITemplateResolver templateResolver() { SpringResourceTemplateResolver templateResolver = new SpringResourceTemplateResolver(); templateResolver.setTemplateMode("HTML5"); templateResolver.setPrefix("/WEB-INF/thymeleaf/"); templateResolver.setSuffix(".html"); templateResolver.setCharacterEncoding("utf-8"); templateResolver.setOrder(1); templateResolver.setCacheable(false); return templateResolver; } @Bean public SpringTemplateEngine templateEngine(ITemplateResolver templateResolver) { SpringTemplateEngine templateEngine = new SpringTemplateEngine(); templateEngine.setTemplateResolver(templateResolver); return templateEngine; } @Bean // public ViewResolver viewResolver() { public ThymeleafViewResolver viewResolver(TemplateEngine templateEngine) { ThymeleafViewResolver viewResolver = new ThymeleafViewResolver(); viewResolver.setTemplateEngine(templateEngine); viewResolver.setCharacterEncoding("utf-8"); return viewResolver; } }前端例子代码：
<!DOCTYPE html> <html xmlns:th="http://www.thymeleaf.org"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <style type="text/css"> label.error{ color:red; } input.error{ background:yellow } </style> </head> <body> //th:object 代表命令对象也就是表单要绑定的对象，跟spring form表单绑定标签中commandName 绑定对象类似 //当请求跳转到该页面需要相应的传一个带有key为user的对象，key默认为该对象类型的小写字母开头 //th:action 代表要提交的表单链接, url格式为 @{} <form th:object="${user}" method="POST" th:action="@{/register}"> //th:if 用来判断表单是否验证有误，有错误则显示出来无错则不显示 <div th:if="${#fields.hasErrors('*')}"> <ul> //th:each遍历错误并通过ul列表显示出来 <li th:each="err:${#fields.errors('*')}" th:text="${err}">输入有误</li> </ul> </div> //判断该字段是否验证有误，有错误则显示相应的css，该css可自定义 <label th:class="${#fields.hasErrors('username')}?'error'">用户名</label> <input type="text" th:field="*{username}" th:class="${#fields.hasErrors('username')}?'error'"> //th:if 判断如果该字段验证错误，则展示span标签及错误信息，如果无错则不展现 <span th:if="${#fields.hasErrors('username')}" th:text="${#fields.errors('username')}"></span> <label th:class="${#fields.hasErrors('password')}?'error'">用户名</label> <input type="text" th:field="*{password}" th:class="${#fields.hasErrors('password')}?'error'"> <input type="submit" value="提交"/> </form> </body> </html>
后台代码controller：
@Controller public class ThyController { @RequestMapping("/toleaf") public String tleaf(Model model){ //向前台添加一个命令对象 //默认key为该类型User->小写字母user //也就是表单中th:object=${user} model.addAttribute(new User()); return "tleaf"; } @RequestMapping("/register") public String register(@Valid User user,Errors errors){ System.out.println(user.getUsername()); if(errors.hasErrors()){ return "tleaf"; } return "success"; } }
