/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
import java.time.*;
import java.time.temporal.*;
 
/* 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
	{
 
        List<String> inputs = new ArrayList<> ();
        inputs.add ( "2016-01-23" );
        inputs.add ( "2016-01-25" );
        inputs.add ( "2016-02-22" ); // End of longest period between dates.
        inputs.add ( "2016-02-25" );
        inputs.add ( "2016-02-28" );
 
        LocalDate longestStart = null;
        LocalDate longestStop = null;
        LocalDate previousDate = null;
        long longestInDays = 0;
 
        for ( String input : inputs ) {
            LocalDate currentDate = LocalDate.parse ( input );
            if ( null == previousDate ) {  // First loop.
                previousDate = currentDate;
                continue;  // Skip the rest of this first loop.
            }
            long currentDays = ChronoUnit.DAYS.between ( previousDate , currentDate );
            if ( currentDays > longestInDays ) {
                // If the current loop exceeds previous longest, remember this one as longest.
                longestInDays = currentDays;
                longestStart = previousDate;
                longestStop = currentDate;
            }
            // Prepare for next loop.
            previousDate = currentDate;
        }
 
        System.out.println ( "Longest period has days: " + longestInDays + " = " + longestStart + "/" + longestStop );
 
	}
}

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