在servlet中使用thymeleaf

2020-01-03 / thymeleaf

在servlet中使用thymeleaf

引入依赖

    <dependency>
      <groupId>org.thymeleaf</groupId>
      <artifactId>thymeleaf</artifactId>
      <version>3.0.11.RELEASE</version>
    </dependency>

配置模板引擎

对于一个应用, 只需要配置一次Thymeleaf就可以了, 每次请求都可以使用同一个TemplateEngine实例. 可以使用单例模式.

package cn.lacknb.thymeleaf;

import org.thymeleaf.TemplateEngine;
import org.thymeleaf.templatemode.TemplateMode;
import org.thymeleaf.templateresolver.ServletContextTemplateResolver;

import javax.servlet.ServletContext;

/*
*  对于一个应用, 只需要配置一次Thymeleaf就可以了. 每次请求
*  都可以使用同一个TemplateEngine实例. 可以使用单例模式
*  代码如下:
* */

public class WebApplication {

    private TemplateEngine templateEngine;
    private static WebApplication webApplication;

    /*
    * 私有构造器
    * */

    private WebApplication(ServletContext servletContext){
        // 创建模板解析器
        ServletContextTemplateResolver templateResolver = new ServletContextTemplateResolver(servletContext);
        // 设置模板模式为HTML
        templateResolver.setTemplateMode(TemplateMode.HTML);
        // 设置前缀与后缀
        templateResolver.setPrefix("/WEB-INF/templates/");
        templateResolver.setSuffix(".html");
        templateResolver.setCharacterEncoding("UTF-8");
        this.templateEngine = new TemplateEngine();
        this.templateEngine.setTemplateResolver(templateResolver);
    }

    public static WebApplication getInstance(ServletContext servletContext){
        if (webApplication == null){
            webApplication = new WebApplication(servletContext);
        }
        return webApplication;
    }

    public TemplateEngine getTemplateEngine(){
        return this.templateEngine;
    }

}

在WebApplication类的构造器中, 对TemplateEngine进行了配置, 并使用ServletContextTemplateResolver作为模板解析器, 分别配置了模板模式, 处理时的前缀与后缀. 在Servlet中, 只需要调用WebApplication的getTemplateEngine方法就可以获得TemplateEngine的实例.

注意: WebApplication使用单例模式, 在单例模式下, 需要提供一个私有的构造器, 一个返回自己实例的方法.

创建Servlet

package cn.lacknb.servlet;

import cn.lacknb.beans.User;
import cn.lacknb.thymeleaf.WebApplication;
import org.thymeleaf.TemplateEngine;
import org.thymeleaf.context.Context;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;


public class UserServlet extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        WebApplication webapp = WebApplication.getInstance(this.getServletContext());
        // 设置用户数据
        // thymeleaf中context
        Context context = new Context();
        context.setVariable("users", getUsers());
        // 获取模板引擎实例
        TemplateEngine engine = webapp.getTemplateEngine();
        String result = engine.process("user", context);
        resp.setContentType("text/html; charset=utf-8");
        // 输出渲染后的HTML
        resp.getWriter().print(result);

//        新建一个user.html, 在WEB-INF/templates/
    }

    private List<User> getUsers(){
        List<User> users = new ArrayList<User>();
        users.add(new User(1, "测试1"));
        users.add(new User(2, "测试2"));
        users.add(new User(3, "测试3"));
        users.add(new User(4, "测试4"));
        users.add(new User(5, "测试5"));
        return users;
    }


}

html文件

user.html

<!DOCTYPE html SYSTEM "http://www.thymeleaf.org/dtd/xhtml1-strict-thymeleaf-4.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="http://66.lacknb.cn/ssm/js/jquery3.3.js"></script>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css"
          integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"
            integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM"
            crossorigin="anonymous"></script>
</head>
<body>
    <table align="center" class="table">
        <tr>
            <td>序号</td>
            <td>姓名</td>
        </tr>
        <tr th:each="user : ${users}">
            <td th:text="${user.id}"></td>
            <td th:text="${user.name}"></td>
        </tr>

    </table>
</body>
</html>

标题：在servlet中使用thymeleaf
作者：gitsilence
地址：https://blog.lacknb.cn/articles/2019/11/26/1577974165539.html