JSTL控制select为默认选择

              <tr>
                    <td>起点：</td>
                    <td>
                        <select <c:if test="${not empty mileageObj.id}"> disabled="disabled"</c:if>>
                            <option value="">请选择</option>
                                <c:forEach var="start" items="${mileageVOObj }">
                                    <option value="<c:out value='${start.startRepertoryUnifyCode}'/>" <c:if test="${start.startRepertoryUnifyCode == mileageObj.startRepertoryUnifyCode}">selected</c:if>>
                                        <c:out value='${start.startRepertoryName}' />
                                    </option>    
                                </c:forEach>
                        </select>
                        <font color="red">*</font>
                        <input id="startRepertoryUnifyCode" name="startRepertoryUnifyCode" type="hidden" value="${mileageObj.startRepertoryUnifyCode }">
                    </td>
                </tr>