How to access request in JspTags?

I want to call request.getContextPath() inside a JSP tag which extends SimpleTagSupport,开发者_C百科 is there any way to do it?

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First get the PageContext by the inherited SimpleTagSupport#getJspContext() and then get the HttpServletRequest by PageContext#getRequest().

PageContext pageContext = (PageContext) getJspContext();  
HttpServletRequest request = (HttpServletRequest) pageContext.getRequest();