/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.time.*;
import java.time.format.*;
 
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String d = "2018-12-31T08:46:01.307Z[UTC]";
		ZonedDateTime funnyDate = ZonedDateTime.parse(d);
 
		String formatted = funnyDate.format(DateTimeFormatter.ofPattern("YYYY/MM/dd"));// 2019/12/31
		System.out.println(formatted);
 
		formatted = funnyDate.format(DateTimeFormatter.ofPattern("yyyy/MM/dd"));// 2018/12/31
		System.out.println(formatted);
	}
}

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