首先，经过本人的测试，freemarker只能调用Java的Public static 方法及属性

背景说明：框架使用的是spring+springmvc+freemarker

package com.zxsd.test.util;

import java.util.HashMap;
import java.util.Map;

public class UrlUtil {
    private static final Map<String, String> urls = new HashMap<String, String>();
    static {
        urls.put("Nwenzhang.css", "/css/Nwenzhang.css");
        urls.put("Guang.css", "/css/Guang.css");
        urls.put("bootstrap.min.css", "/bootstrap/css/bootstrap.min.css");
        urls.put("Nwenzhang.css", "/css/Nwenzhang.css");
    }

    public static String getUrl(String key) {
        return urls.get(key);
    }
}

第一种:

直接将类的实例通过ModelMap传递到前端
Controller中的代码：

</pre><pre name="code" class="java">map.put("urlUtil", new UrlUtil());

HTML页面中的代码：

<#assign name=urlUtl.getUrl("Nwenzhang.css")>${name}

第二种：
定义BaseController 如下：

package com.zxsd.test.action.base;

import org.springframework.stereotype.Controller;

import freemarker.ext.beans.BeansWrapper;
import freemarker.template.TemplateHashModel;
import freemarker.template.TemplateModelException;

@Controller
public class BaseController {
    private final static BeansWrapper wrapper = BeansWrapper
            .getDefaultInstance();
    private final static TemplateHashModel staticModels = wrapper
            .getStaticModels();

    protected static TemplateHashModel useStaticPacker(String packname) {
        TemplateHashModel fileStatics = null;
        try {
            fileStatics = (TemplateHashModel) staticModels.get(packname);
        } catch (TemplateModelException e) {
            e.printStackTrace();
        }
        return fileStatics;
    };

}

其他controller 继承 BaseController ,需要返回静态类时候 如下：

map.put("urlUtil", useStaticPacker("com.zxsd.test.util.UrlUtil"));

在页面中调用：

${UrlUtil.getUrl("Nwenzhang.css")!}

第三种：
定义FreemarkerStaticModels.java 如下：

package com.zxsd.test.util;

import java.util.HashMap;
import java.util.Properties;
import java.util.Set;

import freemarker.ext.beans.BeansWrapper;
import freemarker.template.TemplateHashModel;
/**
 *   处理freeMarker  访问静态类静态方法
 * @author Administrator
 *
 */
public class FreemarkerStaticModels extends HashMap<Object, Object>{

    /**
     *
     */
    private static final long serialVersionUID = 1L;
    private static FreemarkerStaticModels FREEMARKER_STATIC_MODELS;
    private Properties staticModels;

    private FreemarkerStaticModels(){

    }

    public static FreemarkerStaticModels getInstance(){
        if(FREEMARKER_STATIC_MODELS==null){
            FREEMARKER_STATIC_MODELS=new FreemarkerStaticModels();
        }
        return FREEMARKER_STATIC_MODELS;
    }

    public Properties getStaticModels() {
        return staticModels;
    }

    public void setStaticModels(Properties staticModels) {
        if(this.staticModels==null&&staticModels!=null){
            this.staticModels = staticModels;
            Set<String> keys=this.staticModels.stringPropertyNames();
            for (String key : keys) {
                FREEMARKER_STATIC_MODELS.put(key, useStaticPackage(this.staticModels.getProperty(key)));
            }
        }
    }

    public static TemplateHashModel useStaticPackage(String packageName){
        try
        {
          BeansWrapper wrapper = BeansWrapper.getDefaultInstance();
          TemplateHashModel staticModels = wrapper.getStaticModels();
          TemplateHashModel fileStatics = (TemplateHashModel) staticModels.get(packageName);
          return fileStatics;
        }
        catch (Exception e)
        {
           e.printStackTrace();
        }
        return null;
    }

}

定义staticClass.properties

UrlUtil=com.zxsd.test.util.UrlUtil

在springmvc.xml 配置文件中

<!-- freemarker 静态类的配置位置 -->
    <bean id="freemarkerStatic"
        class="org.springframework.beans.factory.config.PropertiesFactoryBean">
        <property name="location" value="classpath:staticClass.properties" />
    </bean>
    <!-- freemarker 静态类的解析配置-->
    <bean id="freemarkerStaticModels"
        class="com.zxsd.test.util.FreemarkerStaticModels" factory-method="getInstance">
        <property name="staticModels" ref="freemarkerStatic"/>
    </bean>
<!-- freemarker视图解析器 -->
    <bean id="freemarkerViewResolver" class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
        <property name="prefix" value="/page/" />
        <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" />
          <!-- freemarker 静态类配置,在原有<span style="line-height: 25.2px; font-family: verdana, Arial, Helvetica, sans-serif;">freemarker视图解析器</span>配置中加入下一行即可 -->
         <span style="white-space:pre">   </span><property name="attributesMap" ref="freemarkerStaticModels"/>
    </bean>

最后说下三种的选择：
第一种后端最简便，什么支持都不用，但是前端比较麻烦。
第一种和第二种是用哪些类就加入哪些类。
第三种是直接返回所有配置的类到页面。