Sometimes we need to check whether a date is within past 24 hours or not. Generally we implement this kind of functionality when we create an AuthToken or a code that we want to to be valid for some time duration.

Example: In the below example I'm checking the provided date is within 24 hours or not.

/**
 * Check date is within 24 hours or not
 * @param generatedDate
 * @return
 */
public static boolean checkGeneratedCodeTime(Date generatedDate)
{
    Calendar calendar = Calendar.getInstance();
    long diff = calendar.getTimeInMillis() - generatedDate.getTime();
    long diffHours = diff / (60 * 60 * 1000);
    System.out.println("diffHours: "+ diffHours);
    if (diffHours >= 24) 
    {
        System.out.println("false: ");
        return false;
    }
    else
    {
        System.out.println("true: ");
        return true;
    }
}

Hope this will help you :)