Sort Map by Keys.
import java . util . HashMap ; import java . util . Map ; import java . util . TreeMap ; public class SortByKeyExample1 { public static void main ( String [ ] args ) { Map < String , String > unsortMap = new HashMap < String , String > ( ) ; unsortMap . put ( "Z" , "z" ) ; unsortMap . put ( "B" , "b" ) ; unsortMap . put ( "A" , "a" ) ; unsortMap . put ( "C" , "c" ) ; unsortMap . put ( "D" , "d" ) ; unsortMap . put ( "E" , "e" ) ; unsortMap . put ( "Y" , "y" ) ; unsortMap . put ( "N" , "n" ) ; unsortMap . put ( "J" , "j" ) ; unsortMap . put ( "M" , "m" ) ; unsortMap . put ( "F" , "f" ) ; System . out . pr...