Check out example codes for "how to compare current date and time with another date and time in android". It will help you in understanding the concepts better.

Code Example 1

Date date1 = calendar1.getTime();
Date date2 = calendar2.getTime();
if (date1.compareTo(date2) > 0)
{    Log.i("app", "Date1 is after Date2");} 
else if (date1.compareTo(date2) < 0) 
{    Log.i("app", "Date1 is before Date2");} 
else if (date1.compareTo(date2) == 0) 
{    Log.i("app", "Date1 is equal to Date2");}

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