Java Utililty Methods Hour Format

SimpleDateFormat df = new SimpleDateFormat("yy-MM-dd");
SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
return (df.format(d) + " " + sdf.format(d));

return formatDateTime(DEFAULT_DATE_FROMAT, date);

return format(date, "yyyy-MM-dd HH:mm:ss");

if (paramDate == null)
    return null;
SimpleDateFormat localSimpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
localSimpleDateFormat.setLenient(false);
return localSimpleDateFormat.format(paramDate);

date = date.replaceAll("Atualizadas em", "").replace(" ", "");
SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyyHH:mm");
try {
    return format.parse(date);
} catch (ParseException e) {
    e.printStackTrace();
    return null;

Date date;
String formattedDate = dateString;
String pattern = (dateString.indexOf('T') == -1) ? "yyyy-MM-dd HH:mm:ss.S" : "yyyy-MM-dd'T'HH:mm:ss";
try {
    date = new SimpleDateFormat(pattern).parse(dateString);
    formattedDate = new SimpleDateFormat("MMMM dd, yyyy, h:mm:ss a").format(date);
} catch (ParseException e) {
    e.printStackTrace();
...

try {
    dateTime = dateTime.substring(0, 22) + dateTime.substring(23, 25);
    String pattern = "yyyy-MM-dd HH:mm:ssZ";
    SimpleDateFormat sdf = new SimpleDateFormat(pattern);
    Date date = sdf.parse(dateTime);
    String newPattern = "dd MMM yyyy h:mm aaa zzz";
    SimpleDateFormat myFormat = new SimpleDateFormat(newPattern);
    return myFormat.format(date);
...

String sDateTime = strDateTime;
try {
    Calendar Cal = parseDateTime(strDateTime);
    SimpleDateFormat sdf = null;
    sdf = new SimpleDateFormat(strFormat);
    sDateTime = sdf.format(Cal.getTime());
} catch (Exception e) {
return sDateTime;

SimpleDateFormat parseFormat = new SimpleDateFormat("dd/mm/yy HH:mm:ss zz");
SimpleDateFormat displayFormat = new SimpleDateFormat("dd/mm/yy hh:mm:ss a zz");
String[] tz = dateStr.split(" ");
TimeZone firstTime = TimeZone.getTimeZone(tz[tz.length - 1]);
parseFormat.setTimeZone(firstTime);
displayFormat.setTimeZone(firstTime);
Date date = null;
try {
...

SimpleDateFormat displayFormat = new SimpleDateFormat("HH:mm");
SimpleDateFormat parseFormat = new SimpleDateFormat("hh:mm a");
Date date = null;
try {
    date = parseFormat.parse("10:30 PM");
} catch (ParseException e) {
    e.printStackTrace();
System.out.println(parseFormat.format(date) + " = " + displayFormat.format(date));