项目开始前准备

此项目是在ssm进行，直接对SSM项目进行修改，因此略去其他步骤，只对修改的内容进行描述

• 首先,pom文件需要添加的内容有

<!--spring 多出来的依赖文件 -->
<dependency>
   <groupId>org.springframework</groupId>
   <artifactId>spring-context-support</artifactId>
   <version>${spring.version}</version>
</dependency>

<!--freemarker依赖文件 -->
<dependency>
  <groupId>org.freemarker</groupId>
  <artifactId>freemarker</artifactId>
  <version>${freemarker.version}</version>
</dependency>

• springmvc-servlet.xml需要添加的设置

<!-- freemarker的配置 -->
    <bean id="freemarkerConfig"
        class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
        <property name="templateLoaderPath" value="WEB-INF/views/" />
        <property name="freemarkerSettings">
            <props>
                <prop key="template_update_delay">0</prop>
                <prop key="default_encoding">UTF-8</prop>
                <prop key="number_format">0.##########</prop>
                <prop key="datetime_format">yyyy-MM-dd HH:mm:ss</prop>
                <prop key="classic_compatible">true</prop>
                <prop key="template_exception_handler">ignore</prop>
            </props>
        </property>
    </bean>

    <!--视图解析器 -->
    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
        <property name="viewClass"
            value="org.springframework.web.servlet.view.freemarker.FreeMarkerView"></property>
        <property name="suffix" value=".html" />
        <property name="contentType" value="text/html;charset=utf-8" />
        <property name="exposeRequestAttributes" value="true" />
        <property name="exposeSessionAttributes" value="true" />
        <property name="exposeSpringMacroHelpers" value="true" />
        <property name="order" value="1" />
    </bean>

目前测试 没有对原有的jsp 视图解析器设置造成不兼容
JSP视图解析器原有配置为

    <!-- 配置内部资源视图解析器 -->
    <bean
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <!-- 这里的配置我的理解是自动给后面action的方法return的字符串加上前缀和后缀，变成一个 可用的url地址 -->
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>

先看一个demo

• 我们先定义一个entity

import java.util.Date;

public class SysUser {
    private Integer userid;

    private String usercode;

    private String username;

    private String password;

    private Integer status;

    private String phonenumber;

    private String email;

    private String creator;

    private Date createtime;

    private String description;

    public Integer getUserid() {
        return userid;
    }

    public void setUserid(Integer userid) {
        this.userid = userid;
    }

    public String getUsercode() {
        return usercode;
    }

    public void setUsercode(String usercode) {
        this.usercode = usercode == null ? null : usercode.trim();
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username == null ? null : username.trim();
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password == null ? null : password.trim();
    }

    public Integer getStatus() {
        return status;
    }

    public void setStatus(Integer status) {
        this.status = status;
    }

    public String getPhonenumber() {
        return phonenumber;
    }

    public void setPhonenumber(String phonenumber) {
        this.phonenumber = phonenumber == null ? null : phonenumber.trim();
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email == null ? null : email.trim();
    }

    public String getCreator() {
        return creator;
    }

    public void setCreator(String creator) {
        this.creator = creator == null ? null : creator.trim();
    }

    public Date getCreatetime() {
        return createtime;
    }

    public void setCreatetime(Date createtime) {
        this.createtime = createtime;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description == null ? null : description.trim();
    }
}

· 然后定义一个Controller

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import com.xqchen.ssm.domain.SysUser;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

@Controller

public class DemoController {

    @RequestMapping("/demo")
    public ModelAndView demo() {
        ModelAndView mv = new ModelAndView("demo");
        mv.addObject("username", "demo ceshi");
        mv.addObject("loglist", this.logList());
        return mv;
    }

    public List<SysUser> logList() {
        List<SysUser> list = new ArrayList<SysUser>();
        for (int i = 0; i < 5; i++) {
            SysUser sysUser = new SysUser();
            sysUser.setCreatetime(new Date());

            sysUser.setUsername("laobiao" + i);

            list.add(sysUser);
        }
        return list;
    }
}

以上 为了从简 我把数据库操作省略了 直接给对象赋值
我在ModelAndView 传了两个对象，分别是 username 和 loglist
我需要新建一个demo.html文件 通过Freemarker引擎取值

• demo.html

<!DOCTYPE html>
<html lang="en">
<head>
   <meta charset="UTF-8">
   <title>Title</title>
</head>
<body>
${username!}
<ul>
   <#list loglist as loglist>
       <li> ${loglist.username}</li>
       <li>${loglist.createtime?string('yyyy-MM-dd')}</li>
   </#list>
</ul>
</body>
</html>

我们可以从下图看到 我们取到了 username 单个值 以及loglist这个集合。

image.png

后面，我们再来讲解Freemarker的语法。