Spring MVC整合FreeMarker

什么是Freemarker?
    FreeMarker是一个用Java语言编写的模板引擎，它基于模板来生成文本输出。FreeMarker与Web容器无关，即在Web运行时，它并不知道Servlet或HTTP。它不仅可以用作表现层的实现技术，而且还可以用于生成XML，JSP或Java 等。
    目前企业中:主要用Freemarker做静态页面或是页面展示

一.工程结构

二.web.xml

<?xml version="1.0" encoding="UTF-8"?>  
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"  
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee      
   http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">  
     
    <display-name>SpringMVC</display-name>  
      
    <context-param>  
        <param-name>contextConfigLocation</param-name>  
        <param-value>/WEB-INF/springMVC-servlet.xml</param-value>  
    </context-param>  
      
    <listener>  
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
    </listener>  
      
    <filter>  
        <filter-name>encodingFilter</filter-name>  
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  
        <init-param>  
            <param-name>encoding</param-name>  
            <param-value>UTF-8</param-value>  
        </init-param>  
        <init-param>  
            <param-name>forceEncoding</param-name>  
            <param-value>true</param-value>  
        </init-param>  
    </filter>  
    <filter-mapping>  
        <filter-name>encodingFilter</filter-name>  
        <url-pattern>/*</url-pattern>  
    </filter-mapping>  
  
    <servlet>  
        <servlet-name>springMVC</servlet-name>  
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
        <load-on-startup>1</load-on-startup>  
    </servlet>  
    <servlet-mapping>  
        <servlet-name>springMVC</servlet-name>  
        <url-pattern>/</url-pattern>  
    </servlet-mapping>  
</web-app>   

三.springMVC-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>  
<beans xmlns="http://www.springframework.org/schema/beans"  
    xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"  
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:schemaLocation="http://www.springframework.org/schema/beans   
                    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd  
                    http://www.springframework.org/schema/context  
                    http://www.springframework.org/schema/context/spring-context-3.0.xsd  
                    http://www.springframework.org/schema/mvc  
                    http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd  
                    ">  
    <!-- 自动扫描包 -->   
    <context:component-scan base-package="com.bijian.study.controller"></context:component-scan>     
      
    <!-- 默认注解映射支持 -->   
    <mvc:annotation-driven></mvc:annotation-driven>  
      
    <!--JSP视图解析器-->  
    <bean id="viewResolverJsp" class="org.springframework.web.servlet.view.InternalResourceViewResolver">  
        <property name="prefix" value="/WEB-INF/views/"/>  
        <property name="suffix" value=".jsp"/>  
        <property name="viewClass" value="org.springframework.web.servlet.view.InternalResourceView"/>  
        <property name="order" value="1"/>  
    </bean>  
      
    <!-- 配置freeMarker视图解析器 -->  
    <bean id="viewResolverFtl" class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">  
        <property name="viewClass" value="org.springframework.web.servlet.view.freemarker.FreeMarkerView"/>  
        <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="cache" value="true" />  
        <property name="suffix" value=".ftl" />  
        <property name="order" value="0"/>  
    </bean>  
  
    <!-- 配置freeMarker的模板路径 -->  
    <bean id="freemarkerConfig" class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">  
        <property name="templateLoaderPath" value="/WEB-INF/ftl/"/>  
        <property name="freemarkerVariables">  
            <map>  
                <entry key="xml_escape" value-ref="fmXmlEscape" />  
            </map>  
        </property>  
        <property name="defaultEncoding" value="UTF-8"/>  
        <property name="freemarkerSettings">  
            <props>  
                <prop key="template_update_delay">3600</prop>  
                <prop key="locale">zh_CN</prop>  
                <prop key="datetime_format">yyyy-MM-dd HH:mm:ss</prop>  
                <prop key="date_format">yyyy-MM-dd</prop>  
                <prop key="number_format">#.##</prop>  
            </props>  
        </property>  
    </bean>  
  
    <bean id="fmXmlEscape" class="freemarker.template.utility.XmlEscape"/>  
</beans>  

      在JSP和Freemarker的配置项中都有一个order property，上面例子是把freemarker的order设置为0，jsp为1，意思是找view时，先找ftl文件，再找jsp文件做为视图。这样Freemarker视图解析器就能与JSP视图解析器并存。

   

四.FreeMarkerController.java

package com.bijian.study.controller;  
  
import java.util.ArrayList;  
import java.util.HashMap;  
import java.util.List;  
import java.util.Map;  
  
import javax.servlet.http.HttpServletRequest;  
import javax.servlet.http.HttpServletResponse;  
  
import org.springframework.stereotype.Controller;  
import org.springframework.web.bind.annotation.RequestMapping;  
import org.springframework.web.servlet.ModelAndView;  
  
import com.alibaba.fastjson.JSON;  
import com.bijian.study.utils.JsonUtil;  
import com.bijian.study.vo.User;  
    
@Controller   
public class FreeMarkerController {     
    
    @RequestMapping("/get/usersInfo")     
    public ModelAndView Add(HttpServletRequest request, HttpServletResponse response) {     
    
        User user = new User();     
        user.setUsername("zhangsan");     
        user.setPassword("1234");  
          
        User user2 = new User();     
        user2.setUsername("lisi");     
        user2.setPassword("123");   
          
        List<User> users = new ArrayList<User>();     
        users.add(user);  
        users.add(user2);  
        return new ModelAndView("usersInfo", "users", users);     
    }  
      
    @RequestMapping("/get/allUsers")     
    public ModelAndView test(HttpServletRequest request, HttpServletResponse response) {  
          
        List<User> users = new ArrayList<User>();     
        User u1 = new User();     
        u1.setUsername("王五");  
        u1.setPassword("123");  
        users.add(u1);  
          
        User u2 = new User();     
        u2.setUsername("张三");  
        u2.setPassword("2345");  
        users.add(u2);  
          
        User u3 = new User();     
        u3.setPassword("fgh");     
        u3.setUsername("李四");  
        users.add(u3);     
          
        Map<String, Object> rootMap = new HashMap<String, Object>();  
        rootMap.put("userList", users);  
        Map<String, String> product = new HashMap<String, String>();  
        rootMap.put("lastProduct", product);  
        product.put("url", "http://www.baidu.com");     
        product.put("name", "green hose");  
          
        String result = JSON.toJSONString(rootMap);  
          
        Map<String, Object> resultMap = new HashMap<String, Object>();  
        resultMap = JsonUtil.getMapFromJson(result);  
          
        return new ModelAndView("allUsers", "resultMap", resultMap);     
    }  
}  

五.JsonUtil.java

package com.bijian.study.utils;  
  
import java.util.Map;  
  
import com.alibaba.fastjson.JSON;  
  
public class JsonUtil {  
  
    public static Map<String, Object> getMapFromJson(String jsonString) {  
        if (checkStringIsEmpty(jsonString)) {  
            return null;  
        }  
        return JSON.parseObject(jsonString);  
    }  
      
    /** 
     * 检查字符串是否为空 
     * @param str 
     * @return 
     */  
    private static boolean checkStringIsEmpty(String str) {  
        if (str == null || str.trim().equals("") || str.equalsIgnoreCase("null")) {  
            return true;  
        }  
        return false;  
    }  
}  

 六.User.java

ackage com.bijian.study.vo;  
  
public class User {  
  
    private String username;  
    private String password;  
  
    public String getUsername() {  
        return username;  
    }  
  
    public void setUsername(String username) {  
        this.username = username;  
    }  
  
    public String getPassword() {  
        return password;  
    }  
  
    public void setPassword(String password) {  
        this.password = password;  
    }  
}  

七.usersInfo.ftl

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">     
<html>     
<head>     
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">     
<title>usersInfo</title>     
</head>     
<body>     
<#list users as user>  
    <div>  
        username : ${user.username},   
        password : ${user.password}  
    </div>  
</#list>     
</body>     
</html>  

八.allUsers.ftl

<html>     
 <head>     
   <title>allUsers</title>     
 </head>     
 <body>     
   <#list resultMap.userList as user>     
       Welcome ${user.username}!&nbsp;&nbsp;id:${user.password}<br/>     
   </#list>     
   <p>Our latest product:     
    <a href="${resultMap.lastProduct.url}">${resultMap.lastProduct.name}  </a>!     
  </body>     
</html>  

九.运行效果

 

 再输入http://localhost:8088/SpringMVC/greeting?name=zhangshan，JSP视图解析器运行依然正常。

至此,就结束完成整合了!