Concatenate 3 JSP field into date format

Concatenate 3 JSP field into date format

I have a date fields in jsp and I want to concatenate them in Java Class
so that it will be save in database as a date format (yyyy-MM-dd
HH:mm:ss). here's my code:
jsp:
<label style="font-size: 17px;">MM</label><br>
<select name="pcmm" id="pcmm" class="sel" style="margin-left: 0;
width: 51px;">
<option selected="selected" value=""
><%=DateUtil.getDateSelectOptions("M") %></option>
</select>
<label class="lab">DD</label>
<select name="pcdd" id="pcdd" class="sel" style="width: 51px;">
<option selected="selected" value=""
><%=DateUtil.getDateSelectOptions("D") %></option>
</select>
<label class="lab">YYYY</label>
<select name="pcyy" id="pcyy" class="sel" style="width: 66px;">
<option selected="selected" value=""
><%=DateUtil.getDateSelectOptions("Y") %></option>
</select>
java class:
private String ror_period_covered;
TblRevenueOfficialReciept ror = new TblRevenueOfficialReciept();
Date date = new Date();
ror.setRorDueDate(ror_due_date);