…

String[] patternExamples = {

"dd MMMMM yyyy",

"dd.MM.yy",

"MM/dd/yy",

"yyyy.MM.dd G 'at' hh:mm:ss z",

"EEE, MMM d, ''yy",

"h:mm a",

"H:mm:ss:SSS",

"K:mm a,z",

"yyyy.MMMMM.dd GGG hh:mm aaa"

};

. . .

JComboBox patternList = new JComboBox(patternExamples);

patternList.setEditable(true);

patternList.addActionListener(this);

Tham khảo thêm tại https://docs.oracle.com/javase/tutorial/uiswing/examples/components/index.html#ComboBoxDemo