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--- java:jfc_intf_sorted_set_map [2015/03/23 06:55] – [java.util.SortedSet] gthanos
+++ java:jfc_intf_sorted_set_map [2020/03/15 18:48] (current) – external edit 127.0.0.1
@@ Line 10: / Line 10: @@
   * **[[http://docs.oracle.com/javase/7/docs/api/java/util/SortedSet.html#subSet(E,%20E)|subSet(E fromElement, E toElement)]] - ** Επιστρέφει το υποσύνολο του Set από fromElement (μαζί με το fromElement) έως toElement (χωρίς το toElement).
-<code java NameSortedSet.java>
+<code java StudentSortedSet.java>
 import java.util.*;
-public class NameSortedSet {
+public class StudentSortedSet {
-   static final Comparator<Name> NameOrdering =
-                                        new Comparator<Name>() {
-            public int compare(Name n1, Name n2) {
-                int cmp = n1.firstName().compareTo(n2.firstName() );
-                return (cmp != 0 ? cmp : n1.lastName().compareTo(n2.lastName() ));
-            }
-    };
-    public static void main(String[] args) {
+  public static void main(String[] args) {
-        SortedSet<Name> names = new TreeSet<Name>(NameOrdering);
+    SortedSet<Student> students = new TreeSet<Student>();
-        names.add(new Name("Bob", "Travolta"));
+    students.add(new Student("John", "Smith"));
-        names.add(new Name("John", "Smith"));
+    students.add(new Student("Stanley", "Peters"));
-        names.add(new Name("Karl", "Ng"));
+    students.add(new Student("Edgar", "Bloch"));
-        names.add(new Name("Jeff", "Smith"));
+    students.add(new Student("Suzan", "Miles"));
-        names.add(new Name("Tom", "Rich"));
+    students.add(new Student("Mary", "Poppins"));
-        for(Name n: names)
+    students.add(new Student("Tom", "Rich"));
-          System.out.println(n);
+    for(Student n: students)
+      System.out.println(n);
-    }
+    System.out.println("\n***Print headset***");
+    SortedSet<Student> subStudents = students.headSet(new Student("Mary", "Poppins"));
+    for(Student s: subStudents)
+      System.out.println(s);
+    System.out.println("\n***Print tailset***");
+    subStudents = students.tailSet(new Student("Mary", "Poppins"));
+    for(Student s: subStudents)
+      System.out.println(s);
+  }
 }
 </code>
+<WRAP center round 60% tip>Στο παραπάνω παράδειγμα δείτε πως αλλάζει η κατάταξη αν αφαιρέσετε τον //Comparator// από τον κατασκευαστή του αντικειμένου //names//.
+</WRAP>
 ===== java.util.SortedMap =====
@@ Line 46: / Line 55: @@
   * **[[http://docs.oracle.com/javase/7/docs/api/java/util/SortedMap.html#subMap(K,%20K)|subMap(K fromKey, K toKey)]] - ** Επιστρέφει το υποσύνολο του Set από fromKey (μαζί με το fromKey) έως toKey (χωρίς το toKey).
+<code java NameProperty.java>
+import java.util.*;
+public class NameProperty {
+  private String email;
+  private String address;
+  public NameProperty(String mail, String address) {
+    this.email = mail;
+    this.address = address;
+  }
+  public String getEmail() { return email; }
+  public String getAddress() { return address; }
+  public void setEmail(String mail) { email = mail; }
+  public void setAddress(String address) { this.address = address; }
+  public String toString() { return "email: "+email+", address: "+address; }
+}
+</code>
+<code java NameSortedMap.java>
+import java.util.*;
+public class NameSortedMap {
+   static final Comparator<Name> NameOrdering =
+                                        new Comparator<Name>() {
+            public int compare(Name n1, Name n2) {
+                int cmp = n1.firstName().compareTo(n2.firstName() );
+                return (cmp != 0 ? cmp : n1.lastName().compareTo(n2.lastName() ));
+            }
+    };
+    public static void main(String[] args) {
+        SortedMap<Name,NameProperty> users = new TreeMap<Name,NameProperty>(NameOrdering);
+        users.put(new Name("Bob", "Travolta"), new NameProperty("bob@travolta.com", "Gklavani 37, 1st floor") );
+        users.put(new Name("John", "Smith"), new NameProperty("john@smith.com", "Gklavani 37, 2nd floor") );
+        users.put(new Name("Karl", "Ng"), new NameProperty("karl@ng.com", "Gklavani 37, 3rd floor") );
+        users.put(new Name("Jeff", "Smith"), new NameProperty("jeff@smith.com", "Gklavani 37, 4th floor") );
+        users.put(new Name("Tom", "Rich"), new NameProperty("tom@rich.com", "Gklavani 37, 5tht floor") );
+        for(Map.Entry<Name,NameProperty> u: users.entrySet())
+          System.out.println(u);
+        System.out.println("\n***Print headmap***");
+        SortedMap<Name,NameProperty> subusers = users.headMap(new Name("Karl", "Ng"));
+        for(Map.Entry<Name,NameProperty> u: subusers.entrySet())
+          System.out.println(u);
+        System.out.println("\n***Print tailmap***");
+        subusers = users.tailMap(new Name("Karl", "Ng"));
+        for(Map.Entry<Name,NameProperty> u: subusers.entrySet())
+          System.out.println(u);
+    }
+}
+</code>
+|Προηγούμενο: [[:java:jfc_intf_sort | Sorting  ]] | [[:toc | Περιεχόμενα ]] | Επόμενο: [[:java:jfc_algorithms| Αλγόριθμοι ]] |