1        /* 
2         * A program to perform some  basic operations on a list of String names 
3         */
4        package arraylists;
5    
6         import java.util.ArrayList;
7         import java.util.List;
8         import java.util.stream.Collectors;
9    
10              class SteamArrayListProcessing {
11   
12                  public static void main(String[] args) {
13                      //POINT A: Add some strings which represent names to an ArrayList.
14                      List<String> names = new ArrayList<>();
15                      names.add("Holiday, Billie");
16                      names.add("Claudel, Camille");
17                      names.add("Picasso, Pablo");
18                      names.add("Gallen-Kallela, Akseli");
19                      names.add("Zotto, Osvaldo");
20                      names.add("LaRosa, Danielle");
21                      names.add("Berk, Erik");
22   
23                      //POINT B: Use map and the toList collector to create an ArrayList of just
24                      //         the first names of the names ArrayList. Use a for loop to print
25                      //         out the names, separated by spaces.
26                      List<String> firstNamesList = names.stream()
27                              .map(n -> firstName(n))
28                              .collect(Collectors.toList());
29                      System.out.print("First names: ");
30                      for (String firstName : firstNamesList) {
31                              System.out.print(firstName + " ");
32                          }
33                      System.out.println();
34   
35                      //POINT C: Use map and the joining collector to create a String of just
36                      //        the first names of the names ArrayList with each name separated
37                      //        by a comma. Print it.
38   
39                      String firstNames = names.stream()
40                              .map(n -> firstName(n))
41                              .collect(Collectors.joining(", "));
42   
43                      System.out.println("First names: " + firstNames);
44   
45   
46                      //POINT D: By analogy from points B and C, print a comma-separated
47                      //list of the last names in the names ArrayList
48   
49                      String lastNames = names.stream()
50                              .map(n -> lastName(n))
51                              .collect(Collectors.joining(", "));
52   
53                      System.out.println("Last names: " + lastNames);
54   
55                      //POINT E: Print a comma-separated list of all uppercase first names
56                      //from the list of names in the names ArrayList
57                      String upperCaseFirstNames = names.stream()
58                              .map(n -> firstName(n))
59                              .map(n -> n.toUpperCase())
60                              .collect(Collectors.joining(", "));
61                      System.out.println("Uppercase first names: " + upperCaseFirstNames);
62   
63                      //POINT F: Print a comma-separated list of all hyphenated last names
64                      // from the list of names in the names ArrayList
65                      String hyphenatedLastNames = names.stream()
66                              .map(n -> lastName(n))
67                              .filter(n -> n.contains("-"))
68                              .collect(Collectors.joining(", "));
69                      System.out.println("Hyphenated last names: " + hyphenatedLastNames);
70   
71   
72                      //POINT G: Print the integer values of the total length of all names in the names ArrayList
73                      int totalLength = names.stream()
74                              .map(n -> n.length())
75                              .reduce(0, (n1, n2) -> n1 + n2);
76                      System.out.println("Total Length: " + totalLength);
77   
78   
79                      //POINT H: Print the integer value of the total length of all
80                      //first names in the names ArrayList
81                      int fNameTotalLength = names.stream()
82                              .map(n -> firstName(n))
83                              .map(n -> n.length())
84                              .reduce(0, (n1, n2) -> n1 + n2);
85                      System.out.println("Total First Name Length: " + fNameTotalLength);
86   
87                      //POINT I: Print the integer value of the product of the length of
88                      //all first names in the name ArrayList
89                      int productLength = names.stream()
90                              .map(n -> firstName(n))
91                              .map(n -> n.length())
92                              .reduce(1, (n1, n2) -> n1 * n2);
93                      System.out.println("Product of first names length: " + productLength);
94   
95   
96                  }
97   
98                  private static String firstName(String directoryStyleName) {
99                     int positionOfComma = directoryStyleName.indexOf(",");
100                    String firstName = directoryStyleName.substring(positionOfComma + 2);     ///Without the +2 the comma shows in the output
101                    return firstName;
102                }
103  
104  
105  
106                private static String lastName(String directoryStyleName) {
107                    int positionOfComma = directoryStyleName.indexOf(",");
108                    String lastName = directoryStyleName.substring(0, positionOfComma);
109                    return lastName;
110                }
111  
112  
113  
114  
115            }
116  
117