In below example for Date format conversion. Here are characters use for date format design.

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 Example

package com.date;

import java.text.SimpleDateFormat;
import java.util.Date;

public class DateFormatChange {

public static String LEGACY_FORMAT = "EEE MMM dd hh:mm:ss zzz yyyy";
public static String ISO_FORMAT = "yyyy-MM-dd'T'HH:mm:ss.SSS zzz";
public static String SHORT_DATE = "yyyy-MM-dd";
private static final String MAIN_DATE_FORMAT = "yyyy-MM-dd'T'hh:mm:ss.SSS'Z'";
private static final String DATE_FORMAT1 = "yyyyMMdd";
private static final String DATE_FORMAT2 = "yyyy/MM/dd";

private static final SimpleDateFormat legacyFormatter = new SimpleDateFormat(LEGACY_FORMAT);
private static final SimpleDateFormat isoFormatter = new SimpleDateFormat(ISO_FORMAT);
private static final SimpleDateFormat shortFormatter = new SimpleDateFormat(SHORT_DATE);

public static void main(String[] args) {
Date date = new Date();
System.out.println("Default Date Format:" + date);
System.out.println("Legacy Date Format:" + legacyFormatter.format(date));
System.out.println("ISO Date Format:" + isoFormatter.format(date));
System.out.println("Short Date Format:" + shortFormatter.format(date));
// Other Date Format
SimpleDateFormat formatter = new SimpleDateFormat(DATE_FORMAT1);
System.out.println("Short Date Format1:" + formatter.format(date));
formatter = new SimpleDateFormat(DATE_FORMAT2);
System.out.println("Short Date Format2:" + formatter.format(date));
formatter = new SimpleDateFormat(MAIN_DATE_FORMAT);
System.out.println("Main Date Format:" + formatter.format(date));
	}
}

Output

Default Date Format:Sat Jul 28 13:35:28 PDT 2018
Legacy Date Format:Sat Jul 28 01:35:28 PDT 2018
ISO Date Format:2018-07-28T13:35:28.245 PDT
Short Date Format:2018-07-28
Short Date Format1:20180728
Short Date Format2:2018/07/28
Main Date Format:2018-07-28T01:35:28.245Z

Date pattern Examples

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