关于 jsp tags 的问题

[coolsunwind]

在 doStartTag()的方法中。
RequestUtils.lookup(pageContext, getName(), getScope())；的返回值是null。
请问原因是什么，如何解决！

[liwei_0223]

贴源代码，你这问的云山雾罩的，谁知道怎么回答！

[coolsunwind]

AuthorityTrueThenTag
TreeMap authState = new TreeMap();
try{
authState = (TreeMap)RequestUtils.lookup(pageContext, getName(), getScope());
Object state state = authState.get(getAction());

if(state == null){
return (SKIP_BODY);
}
} catch(Exception e){
ResponseUtils.write(pageContext, e.getMessage());
}
return (EVAL_PAGE);


jsp

<jamp2authority:authorityTrueThen action="MNUMHC" name="authority" scope="request">
<SPAN CLASS="MENU_LINK"><A href="manhourMenuDisplay.do" onclick="return CheckSubmit();">管理</A></SPAN>
</jamp2authority:authorityTrueThen>
<jamp2authority:authorityFalseThen action="MNUMHC" name="authority" scope="request">
管理
</jamp2authority:authorityFalseThen>

[coolsunwind]

jsp 的代码是

<%@ taglib uri="/WEB-INF/tlds/jamp2-authority.tld" prefix="jamp2authority" %>


<jamp2authority:authorityTrueThen action="MNUMHC" name="authority" scope="request">
<SPAN CLASS="MENU_LINK"><A href="manhourMenuDisplay.do" onclick="return CheckSubmit();">管理</A></SPAN>
</jamp2authority:authorityTrueThen>
<------------------------------------------->
tld文件的代码是：

<tag>
<name>authorityTrueThen</name>
<tagclass>jamp2.web.taglib.authority.AuthorityTrueThenTag</tagclass>
<bodycontent>JSP</bodycontent>
<attribute>
<name>action</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>scope</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
<attribute>
<name>name</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
</attribute>
</tag>

<-------------------------------------------------------->

AuthorityTrueThenTag类的代码是

public int doStartTag() throws JspException{
TreeMap authState = new TreeMap();
try{

authState = (TreeMap)RequestUtils.lookup(pageContext, getName(), getScope()); //这个为空！！
Object state = authState.get(getAction());


if(state == null){
return (SKIP_BODY);
}
} catch(Exception e){
ResponseUtils.write(pageContext, e.getMessage());
}
return (EVAL_PAGE);
}