JSP界面的的传输值,该怎么处理

 <% 

  

  readerbean rb = (readerbean) request.getAttribute("rs");

  求这里的判断怎么写  这里没加判断页面会在  下面的value = '<%=rb.getReaderName()%>' 报错

%>

                  <tr>

                    <td align="center"><table width="96%" border="0" cellpadding="0" cellspacing="0">

                        <tr>

                          <td height="27">姓&nbsp;&nbsp;&nbsp;&nbsp;名：

                            <input name="readername" type="text" id="readername"  value = '<%=rb.getReaderName()%>' ></td>

                          <td>性&nbsp;&nbsp;&nbsp;&nbsp;别：

                            <input name="sex" type="text" id="sex" value=""></td>

                          <td>读者类型：

                            <input name="readerType" type="text" id="readerType" value=""></td>

                        </tr>

                        <tr>

                          <td height="27">证件类型：

                            <input name="paperType" type="text" id="paperType" value=""></td>

                          <td>证件号码：

                            <input name="paperNo" type="text" id="paperNo" value=""></td>

                          <td>可借数量：

                            <input name="number" type="text" id="number" value="" size="17">册

                            &nbsp;</td>

                        </tr>

 <% 

      readerbean rb = (readerbean) request.getAttribute("rs");

      if (null != rb) {

%>

                  <tr>

                    <td align="center"><table width="96%" border="0" cellpadding="0" cellspacing="0">

                        <tr>

                          <td height="27">姓&nbsp;&nbsp;&nbsp;&nbsp;名：

                            <input name="readername" type="text" id="readername"  value = '<%=rb.getReaderName()%>' ></td>

                          <td>性&nbsp;&nbsp;&nbsp;&nbsp;别：

                            <input name="sex" type="text" id="sex" value=""></td>