spring mvc项目中利用freemarker生成自定义标签

spring mvc +freemarker的项目中，我们想要在html页面上利用自定义标签，来方便完成我们的一些功能，除了在页面上定义标签外，我们还可以利用程序来定义。
首先要写一个类UpperDirective.Java来实现TemplateDirectiveModel接口，
代码如下：
[java] view plain copy
public class UpperDirective implements TemplateDirectiveModel  {  
  
    @Override  
    public void execute(Environment env, Map map, TemplateModel[] templateModels,  
            TemplateDirectiveBody body) throws TemplateException, IOException {  
        if(!map.isEmpty()){  
            throw new TemplateModelException("this directive doesn't allow parameters");  
        }  
        if(templateModels.length!=0){  
            throw new TemplateModelException("this directive doesn't allow variables");  
        }  
        if(body!=null){  
            body.render(new UpperCaseFilterWriter(env.getOut()));  
        }else{  
            throw new RuntimeException("missing body");  
        }  
    }  
  
      
  
}  
class UpperCaseFilterWriter extends Writer{  
  
    private final Writer out;  
      
    public UpperCaseFilterWriter(Writer out) {  
        this.out=out;  
    }  
    @Override  
    public void write(char[] cbuf, int off, int len) throws IOException {  
        char[] transformedCbuf = new char[len];  
        for(int i=0;i<len;i++){  
            transformedCbuf[i]=Character.toUpperCase(cbuf[i+off]);  
        }  
        out.write(transformedCbuf);  
    }  
  
    @Override  
    public void flush() throws IOException {  
        out.flush();  
    }  
  
    @Override  
    public void close() throws IOException {  
        out.close();  
          
    }  
      
}  
然后在配置文件中进行配置：
[html] view plain copy
<bean id="freemarkerConfig"   
        class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">  
        <property name="templateLoaderPath">  
              <value>/ftl/</value>  
        </property>  
        <property name="freemarkerSettings">  
            <props>  
                <prop key="locale">zh_CN</prop>  
                <prop key="defaultEncoding">UTF-8</prop>  
                <prop key="date_format">yyyy-MM-dd</prop>  
                <prop key="time_format">HH:mm:ss</prop>  
                <prop key="datetime_format">yyyy-MM-dd HH:mm:ss</prop>  
                <prop key="number_format">0.################</prop>  
            </props>  
        </property>  
        <property name="freemarkerVariables">  
            <map>  
                <entry key="upper" value-ref="upperDirective"></entry>  
            </map>  
        </property>    
    </bean>  
      
     <bean id="upperDirective" class="com.nbsh.cms.util.UpperDirective"></bean>   

在页面上输出的标签：<@upper>hh</@upper>  就能输出大写的：HH了。

 http://blog.csdn.net/uk8692/article/details/38176263