1    package arraylists;
2    
3    import java.util.ArrayList;
4    import java.util.List;
5    import java.util.stream.Collectors;
6    
7    public class StreamArrayListProcessing {
8    
9        public static void main(String[] args){
10           List<String> names = new ArrayList<>();
11           names.add("Holiday, Billie");
12           names.add("Claudel, Camille");
13           names.add("Picasso, Pablo");
14           names.add("Gallen-Kallela, Akseli");
15           names.add("Zotto, Osvaldo");
16           names.add("Rodriguez, Deysy");
17           names.add("Cortez, Brenda");
18   
19           //First names
20           List<String> firstNamesList = names.stream()
21                   .map(n -> firstName(n))
22                   .collect(Collectors.toList());
23   
24           System.out.print("First names: ");
25           for (String firstName : firstNamesList){
26               System.out.print(firstName + " ");
27           }
28           System.out.println();
29           String firstNames = names.stream()
30                   .map(n -> firstName(n))
31                   .collect(Collectors.joining(", "));
32           System.out.println("First names: " + firstNames);
33   
34           //Last names
35           List<String> lastNamesList = names.stream()
36                   .map(n -> lastName(n))
37                   .collect(Collectors.toList());
38   
39           System.out.print("Last names: ");
40           for (String lastName : lastNamesList){
41               System.out.print(lastName + " ");
42           }
43           System.out.println();
44           String lastNames = names.stream()
45                   .map(n -> lastName(n))
46                   .collect(Collectors.joining(", "));
47           System.out.println("Last names: " + lastNames);
48   
49           //First names to uppercase
50           String upperCaseFirstNames = names.stream()
51                   .map(n -> firstName(n))
52                   .map(n -> n.toUpperCase())
53                   .collect(Collectors.joining(", "));
54           System.out.println("Uppercase first names: " + upperCaseFirstNames);
55   
56           //Names with hyphens
57           String hyphenatedLastNames = names.stream()
58                   .map(n -> lastName(n))
59                   .filter(n -> n.contains("-"))
60                   .collect(Collectors.joining(", "));
61           System.out.println("Hyphenated last names: " + hyphenatedLastNames);
62   
63           //Total name length
64           int totalLength = names.stream()
65                   .map(n -> n.length())
66                   .reduce(0, (n1, n2) -> n1 + n2);
67           System.out.println("Total length: " + totalLength);
68   
69           //Total first name length
70           int totalFirstLength = firstNamesList.stream()
71                   .map(n -> n.length())
72                   .reduce(0, (n1, n2) -> n1 + n2);
73           System.out.println("Total first name length: " + totalFirstLength);
74   
75           //Product total of names
76           int totalProductLength = names.stream()
77                   .map(n -> n.length())
78                   .reduce(1, (n1, n2) -> n1 * n2);
79           System.out.println("Total product length: " + totalProductLength);
80       }
81   
82       public static int productNameLength(List<String> names){
83           int totalLength = 1;
84           for (String name : names){
85               totalLength = totalLength * name.length();
86           }
87           return totalLength;
88       }
89   
90       private static String firstName(String directoryStyleName) {
91           int commaPosition = directoryStyleName.indexOf(",");
92           return directoryStyleName.substring((commaPosition + 2), (directoryStyleName.length()));
93       }
94   
95       private static String lastName(String directoryStyleName) {
96           int commaPosition = directoryStyleName.indexOf(",");
97           return directoryStyleName.substring(0, commaPosition);
98       }
99   }
100  
101