java代码收藏:获取HttpServletRequest中某一前缀的参数

public static Map getParametersStartingWith(ServletRequest request, String prefix)  
    {  
        Enumeration paramNames = request.getParameterNames();  
        Map params = new TreeMap();  
        if(prefix == null)prefix = "";  
        while(paramNames != null && paramNames.hasMoreElements())   
        {  
            String paramName = (String)paramNames.nextElement();  
            if("".equals(prefix) || paramName.startsWith(prefix))  
            {  
                String unprefixed = paramName.substring(prefix.length());  
                String values[] = request.getParameterValues(paramName);  
                if(values != null && values.length != 0)  
                    if(values.length >





 1)  
                        params.put(unprefixed, values);  
                    else  
                        params.put(unprefixed, values[0]);  
            }  
        }  
        return params;  
    }