Source of CountingStringsOfLength3.java


  1: //CountingStringsOfLength3.java

  3: import java.util.Arrays;
  4: import java.util.List;

  6: public class CountingStringsOfLength3
  7: {
  8:     public static void main(String args[])
  9:     {
 10:         //We will count the strings of length 3 in the following
 11:         //list of strings:
 12:         List<String> strings
 13:             = Arrays.asList("abc", "", "bc", "efg", "abcd", "", "jkl", "mno");
 14:         System.out.println("\nList of strings: " + strings);

 16:         System.out.println("\n=============");
 17:         System.out.println("Using Java 7: ");
 18:         int count = 0;
 19:         for (String string : strings)
 20:         {
 21:             if (string.length() == 3)
 22:             {
 23:                 count++;
 24:             }
 25:         }
 26:         System.out.println("Number of strings of length 3: " + count);

 28:         System.out.println("\n=============");
 29:         System.out.println("Using Java 8: ");
 30:         System.out.println
 31:         (
 32:             "Number of strings of length 3: " + strings
 33:             .stream()
 34:             .filter(string -> string.length() == 3)
 35:             .count()
 36:         );
 37:     }
 38: }
 39: /*  Output:

 41:     List of strings: [abc, , bc, efg, abcd, , jkl, mno]

 43:     =============
 44:     Using Java 7:
 45:     Number of strings of length 3: 4

 47:     =============
 48:     Using Java 8:
 49:     Number of strings of length 3: 4
 50: */