Servlet 整合Thylemeaf （基于Maven构建）

      由于JSP的种种原因，现在web项目中视图层逐步转向视图模板：FreeMarker、Thylemeaf等，但是关于Thylemeaf的使用基本都是基于和Spring、SpringMVC 整合的，也有部分基于Servlet整合的（基于jar文件的形式），最近由于教学需要，和技术更新等web课程部分逐步弱化JSP，而去强化Maven和Thylemeaf，所以进行了Thylemeaf和Maven的整合，这对充分了解Thylemeaf和web相关的内容会有一个更深的了解，对于后面的内容也有一定的帮助。首先需要pom.xml文件需要导入thylemeaf的依赖：

 <dependency>
          <groupId>org.thymeleafgroupId>
          <artifactId>thymeleafartifactId>
          <version>3.0.15.RELEASEversion>
 dependency>

web.xml文件配置（视图的前缀和后缀）

   <context-param>
        <param-name>prefixparam-name>
        <param-value>/WEB-INF/view/param-value>
    context-param>
    
    <context-param>
        <param-name>suffixparam-name>
        <param-value>.htmlparam-value>
    context-param>

Thylemeaf的工具类（主要完成对页面进行渲染前的准备工作）

 
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.WebContext;
import org.thymeleaf.templatemode.TemplateMode;
import org.thymeleaf.templateresolver.ServletContextTemplateResolver;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
 
/**
 * Thymeleaf 视图处理
 * @author TonySong
 */
public class ThymeleafViewServlet extends HttpServlet {
 
    private TemplateEngine templateEngine;
 
    @Override
    public void init() throws ServletException {
        //获取ServletContext对象
        ServletContext servletContext = this.getServletContext();
        //创建Thymeleaf解析对象
        ServletContextTemplateResolver templateResolver =
                new ServletContextTemplateResolver(servletContext);
         //设置模板模式为HTML
        templateResolver.setTemplateMode(TemplateMode.HTML);
        //从web.xml文件获取视图的前缀
        String prefix = servletContext.getInitParameter("prefix");
        System.out.println("prefix>>>>>>>>>>>>>"+prefix);
        templateResolver.setPrefix("/WEB-INF/view/");
        //获取后缀
        String suffix = servletContext.getInitParameter("suffix");
        System.out.println("suffix....>"+suffix);
        templateResolver.setSuffix(".html");
        //关闭缓存
        templateResolver.setCacheable(false);
        //设置编码方式
        templateResolver.setCharacterEncoding("utf-8");
        //实例化视图引擎
        this.templateEngine = new TemplateEngine();
        //设置视图引擎为templateResolver
        this.templateEngine.setTemplateResolver(templateResolver);
    }
 
    protected void processTemplate(String templateName, HttpServletRequest req, HttpServletResponse resp) throws IOException,ServletException{
          resp.setContentType("text/html;charset=utf-8");
          req.setCharacterEncoding("utf-8");
          //根据请求对象和响应对象和全局对象创建web上下文全局对象
          WebContext context = new WebContext(req, resp, getServletContext());
          //根据模板名称和全局对象并依据响应输出流来渲染页面： 前缀+名称+后缀 /WEB-INF/view/list.html
          this.templateEngine.process(templateName,context,resp.getWriter());
    }
}

Servlet：

@WebServlet( urlPatterns = {"/list"})
public class HelloServlet extends ThymeleafViewServlet {
 
    private StudentDao studentDao = new StudentDaoImpl();
 
    protected void list(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String currentPage=req.getParameter("currentPage");
        Pager pager=  this.studentDao.pageList(currentPage, 5);
        pager.setUrl("list");
        req.setAttribute("pager", pager);
        this.processTemplate("list", req, resp);
    }
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
                String path = req.getServletPath();
                switch (path){
                    case "/list": this.list(req, resp);break;
                }
    }
}