Automated date field

The first thing to do is to right click on the date GUI and review the HTML. Then it depends if you can select a static date, or current date (i.e. just click on the “Today” link), or if you need to input a specific date (dynamic).

Maybe try

I created two objects based on the HTML of OUR Calendar GUI: select_DatePickerMonth and select_DatePickerYear. For these two objects, I used a simple xpath for each–again, review your HTML.
select_DatePickerMonth
//select[@class="ui-datepicker-month" and @data-handler="selectMonth"]

select_DatePickerYear
//select[@class="ui-datepicker-year" and @data-handler="selectYear"]

"click on date input field"
WebUI.click(findTestObject('myPage/input_ADate'))

Date todaysDate = new Date()
dayPart = todaysDate[Calendar.DAY_OF_MONTH]
monthPart = todaysDate[Calendar.MONTH]
yearPart = todaysDate[Calendar.YEAR] 

"set the month"
WebUI.waitForElementClickable(findTestObject('myPage/select_DatePickerMonth'), 10)
"get the VALUE of this element"
WebUI.selectOptionByValue(findTestObject('myPage/select_DatePickerMonth'), monthPart.toString(), false)

"set the year"
WebUI.waitForElementClickable(findTestObject('myPage/select_DatePickerYear'), 10)
"get the LABEL of this element"
WebUI.selectOptionByLabel(findTestObject('myPage/select_DatePickerYear'), yearPart.toString(), false)

"set the day"
WebElement selCalendarTable = driver.findElement(By.xpath('//table[@class="ui-datepicker-calendar"]/tbody'))

List<WebElement> Rows = selCalendarTable.findElements(By.tagName('tr'))

Loop:
for (int i = 0; i < Rows.size(); i++) {

	'To locate columns(cells) of that specific row'
	List<WebElement> Cols = Rows.get(i).findElements(By.tagName('td'))

	for (int j = 0; j < Cols.size(); j++) {

		if (Cols.get(j).getText().equals(dayPart.toString())) {
			WebUI.comment("found day ${dayPart}" )
			Cols[j].click();
			break Loop;
		}
	}
}