Do I use Trie correctly for implementation of a phonebook?












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I implemented a PhoneBook utilizing a Trie data structure.



Could I ask you to evaluate it?



Did I apply Trie correctly for such case or is it better to store data somehow else?



I'm looking not only for working solution but also for an optimal one in terms of run-time and storage.



From my calculations, it takes NlogT to add() and get() where N is a number of chars and T is a number of children.



Am I right?



Here is the logic



public final class PhoneBook {

private final Node name;

private final Node surname;

private final Comparator<Record> comparator;

public PhoneBook() {
this.name = new Node();
this.surname = new Node();
comparator = (r1, r2) -> {
int result = r1.getName().compareTo(r2.getName());
if (result == 0) {
result = r1.getSurname().compareTo(r2.getSurname());
if (result == 0) {
result = r1.getNumber().compareTo(r2.getNumber());
}
}
return result;
};
}

public void add(final Record record) {
add(record.getName().toLowerCase(), record, name);
add(record.getSurname().toLowerCase(), record, surname);
}

public SortedSet<Record> get(final String prefix) {
final String lc = prefix.toLowerCase();
final List<Record> recordsRetrievedByName = get(lc, name);
final List<Record> recordsRetrievedBySurname = get(lc, surname);
final SortedSet<Record> result = new TreeSet<>(comparator);
result.addAll(recordsRetrievedByName);
result.addAll(recordsRetrievedBySurname);
return result;
}

private List<Record> get(final String prefix, final Node ancestor) {
Node node = ancestor;
for (final char c: prefix.toCharArray()) {
final Node child = node.children.get(c);
if (child == null) {
return Collections.emptyList();
}
node = child;
}
return node.records;
}

private void add(final String str, final Record record, final Node ancestor) {
Node node = ancestor;
for (final char c: str.toCharArray()) {
final Node child;
if (node.children.containsKey(c)) {
child = node.children.get(c);
} else {
child = new Node();
node.children.put(c, child);
}
child.records.add(record);
node = child;
}
}

private static final class Node {

private final Map<Character, Node> children = new TreeMap<>();

private final List<Record> records = new ArrayList<>();

}

}


And the Record immutable object



public final class Record {



private final String name;

private final String surname;

private final String number;

//constructor, getters, toString
}









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    0












    $begingroup$


    I implemented a PhoneBook utilizing a Trie data structure.



    Could I ask you to evaluate it?



    Did I apply Trie correctly for such case or is it better to store data somehow else?



    I'm looking not only for working solution but also for an optimal one in terms of run-time and storage.



    From my calculations, it takes NlogT to add() and get() where N is a number of chars and T is a number of children.



    Am I right?



    Here is the logic



    public final class PhoneBook {

    private final Node name;

    private final Node surname;

    private final Comparator<Record> comparator;

    public PhoneBook() {
    this.name = new Node();
    this.surname = new Node();
    comparator = (r1, r2) -> {
    int result = r1.getName().compareTo(r2.getName());
    if (result == 0) {
    result = r1.getSurname().compareTo(r2.getSurname());
    if (result == 0) {
    result = r1.getNumber().compareTo(r2.getNumber());
    }
    }
    return result;
    };
    }

    public void add(final Record record) {
    add(record.getName().toLowerCase(), record, name);
    add(record.getSurname().toLowerCase(), record, surname);
    }

    public SortedSet<Record> get(final String prefix) {
    final String lc = prefix.toLowerCase();
    final List<Record> recordsRetrievedByName = get(lc, name);
    final List<Record> recordsRetrievedBySurname = get(lc, surname);
    final SortedSet<Record> result = new TreeSet<>(comparator);
    result.addAll(recordsRetrievedByName);
    result.addAll(recordsRetrievedBySurname);
    return result;
    }

    private List<Record> get(final String prefix, final Node ancestor) {
    Node node = ancestor;
    for (final char c: prefix.toCharArray()) {
    final Node child = node.children.get(c);
    if (child == null) {
    return Collections.emptyList();
    }
    node = child;
    }
    return node.records;
    }

    private void add(final String str, final Record record, final Node ancestor) {
    Node node = ancestor;
    for (final char c: str.toCharArray()) {
    final Node child;
    if (node.children.containsKey(c)) {
    child = node.children.get(c);
    } else {
    child = new Node();
    node.children.put(c, child);
    }
    child.records.add(record);
    node = child;
    }
    }

    private static final class Node {

    private final Map<Character, Node> children = new TreeMap<>();

    private final List<Record> records = new ArrayList<>();

    }

    }


    And the Record immutable object



    public final class Record {



    private final String name;

    private final String surname;

    private final String number;

    //constructor, getters, toString
    }









    share|improve this question







    New contributor




    Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.







    $endgroup$















      0












      0








      0





      $begingroup$


      I implemented a PhoneBook utilizing a Trie data structure.



      Could I ask you to evaluate it?



      Did I apply Trie correctly for such case or is it better to store data somehow else?



      I'm looking not only for working solution but also for an optimal one in terms of run-time and storage.



      From my calculations, it takes NlogT to add() and get() where N is a number of chars and T is a number of children.



      Am I right?



      Here is the logic



      public final class PhoneBook {

      private final Node name;

      private final Node surname;

      private final Comparator<Record> comparator;

      public PhoneBook() {
      this.name = new Node();
      this.surname = new Node();
      comparator = (r1, r2) -> {
      int result = r1.getName().compareTo(r2.getName());
      if (result == 0) {
      result = r1.getSurname().compareTo(r2.getSurname());
      if (result == 0) {
      result = r1.getNumber().compareTo(r2.getNumber());
      }
      }
      return result;
      };
      }

      public void add(final Record record) {
      add(record.getName().toLowerCase(), record, name);
      add(record.getSurname().toLowerCase(), record, surname);
      }

      public SortedSet<Record> get(final String prefix) {
      final String lc = prefix.toLowerCase();
      final List<Record> recordsRetrievedByName = get(lc, name);
      final List<Record> recordsRetrievedBySurname = get(lc, surname);
      final SortedSet<Record> result = new TreeSet<>(comparator);
      result.addAll(recordsRetrievedByName);
      result.addAll(recordsRetrievedBySurname);
      return result;
      }

      private List<Record> get(final String prefix, final Node ancestor) {
      Node node = ancestor;
      for (final char c: prefix.toCharArray()) {
      final Node child = node.children.get(c);
      if (child == null) {
      return Collections.emptyList();
      }
      node = child;
      }
      return node.records;
      }

      private void add(final String str, final Record record, final Node ancestor) {
      Node node = ancestor;
      for (final char c: str.toCharArray()) {
      final Node child;
      if (node.children.containsKey(c)) {
      child = node.children.get(c);
      } else {
      child = new Node();
      node.children.put(c, child);
      }
      child.records.add(record);
      node = child;
      }
      }

      private static final class Node {

      private final Map<Character, Node> children = new TreeMap<>();

      private final List<Record> records = new ArrayList<>();

      }

      }


      And the Record immutable object



      public final class Record {



      private final String name;

      private final String surname;

      private final String number;

      //constructor, getters, toString
      }









      share|improve this question







      New contributor




      Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.







      $endgroup$




      I implemented a PhoneBook utilizing a Trie data structure.



      Could I ask you to evaluate it?



      Did I apply Trie correctly for such case or is it better to store data somehow else?



      I'm looking not only for working solution but also for an optimal one in terms of run-time and storage.



      From my calculations, it takes NlogT to add() and get() where N is a number of chars and T is a number of children.



      Am I right?



      Here is the logic



      public final class PhoneBook {

      private final Node name;

      private final Node surname;

      private final Comparator<Record> comparator;

      public PhoneBook() {
      this.name = new Node();
      this.surname = new Node();
      comparator = (r1, r2) -> {
      int result = r1.getName().compareTo(r2.getName());
      if (result == 0) {
      result = r1.getSurname().compareTo(r2.getSurname());
      if (result == 0) {
      result = r1.getNumber().compareTo(r2.getNumber());
      }
      }
      return result;
      };
      }

      public void add(final Record record) {
      add(record.getName().toLowerCase(), record, name);
      add(record.getSurname().toLowerCase(), record, surname);
      }

      public SortedSet<Record> get(final String prefix) {
      final String lc = prefix.toLowerCase();
      final List<Record> recordsRetrievedByName = get(lc, name);
      final List<Record> recordsRetrievedBySurname = get(lc, surname);
      final SortedSet<Record> result = new TreeSet<>(comparator);
      result.addAll(recordsRetrievedByName);
      result.addAll(recordsRetrievedBySurname);
      return result;
      }

      private List<Record> get(final String prefix, final Node ancestor) {
      Node node = ancestor;
      for (final char c: prefix.toCharArray()) {
      final Node child = node.children.get(c);
      if (child == null) {
      return Collections.emptyList();
      }
      node = child;
      }
      return node.records;
      }

      private void add(final String str, final Record record, final Node ancestor) {
      Node node = ancestor;
      for (final char c: str.toCharArray()) {
      final Node child;
      if (node.children.containsKey(c)) {
      child = node.children.get(c);
      } else {
      child = new Node();
      node.children.put(c, child);
      }
      child.records.add(record);
      node = child;
      }
      }

      private static final class Node {

      private final Map<Character, Node> children = new TreeMap<>();

      private final List<Record> records = new ArrayList<>();

      }

      }


      And the Record immutable object



      public final class Record {



      private final String name;

      private final String surname;

      private final String number;

      //constructor, getters, toString
      }






      java algorithm tree complexity trie






      share|improve this question







      New contributor




      Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question







      New contributor




      Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|improve this question




      share|improve this question






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      Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      asked 11 mins ago









      PavelPavel

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      New contributor




      Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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      New contributor





      Pavel is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






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      Check out our Code of Conduct.






















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