You need to add several indicator optional input parameters, one for each time unit - date, hour, minute, etc.
optInputParameterInfos = new OptInputParameterInfo[] {
new OptInputParameterInfo("date", OptInputParameterInfo.Type.OTHER, new IntegerRangeDescription(1, 1, 31, 1)),
new OptInputParameterInfo("hour", OptInputParameterInfo.Type.OTHER, new IntegerRangeDescription(12, 0, 23, 1)),
new OptInputParameterInfo("minute", OptInputParameterInfo.Type.OTHER, new IntegerRangeDescription(1, 0, 59, 1))
};