Abstract out Set<Tag> into new Tags class

src/main/java/seedu/address/logic/Messages.java

@@ -43,8 +43,8 @@ public static String format(Person person) {
                 .append(person.getEmail())
                 .append("; Address: ")
                 .append(person.getAddress())
-                .append("; Tags: ");
-        person.getTags().forEach(builder::append);
+                .append("; Tags: ")
+                .append(person.getTags());
         return builder.toString();
     }
 

src/main/java/seedu/address/logic/commands/EditCommand.java

@@ -8,25 +8,22 @@
 import static seedu.address.logic.parser.CliSyntax.PREFIX_TAG;
 import static seedu.address.model.Model.PREDICATE_SHOW_ALL_PERSONS;
 
-import java.util.Collections;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
-import java.util.Set;
 
 import seedu.address.commons.core.index.Index;
 import seedu.address.commons.util.CollectionUtil;
 import seedu.address.commons.util.ToStringBuilder;
 import seedu.address.logic.Messages;
 import seedu.address.logic.commands.exceptions.CommandException;
 import seedu.address.model.Model;
-import seedu.address.model.person.Address;
-import seedu.address.model.person.Email;
-import seedu.address.model.person.Name;
 import seedu.address.model.person.Person;
-import seedu.address.model.person.Phone;
-import seedu.address.model.tag.Tag;
+import seedu.address.model.person.fields.mandatory.Address;
+import seedu.address.model.person.fields.mandatory.Email;
+import seedu.address.model.person.fields.mandatory.Name;
+import seedu.address.model.person.fields.mandatory.Phone;
+import seedu.address.model.person.fields.optional.Tags;
 
 /**
  * Edits the details of an existing person in the address book.
@@ -99,7 +96,7 @@ private static Person createEditedPerson(Person personToEdit, EditPersonDescript
         Phone updatedPhone = editPersonDescriptor.getPhone().orElse(personToEdit.getPhone());
         Email updatedEmail = editPersonDescriptor.getEmail().orElse(personToEdit.getEmail());
         Address updatedAddress = editPersonDescriptor.getAddress().orElse(personToEdit.getAddress());
-        Set<Tag> updatedTags = editPersonDescriptor.getTags().orElse(personToEdit.getTags());
+        Tags updatedTags = editPersonDescriptor.getTags().orElse(personToEdit.getTags());
 
         return new Person(updatedName, updatedPhone, updatedEmail, updatedAddress, updatedTags);
     }
@@ -137,7 +134,7 @@ public static class EditPersonDescriptor {
         private Phone phone;
         private Email email;
         private Address address;
-        private Set<Tag> tags;
+        private Tags tags;
 
         public EditPersonDescriptor() {}
 
@@ -196,17 +193,17 @@ public Optional<Address> getAddress() {
          * Sets {@code tags} to this object's {@code tags}.
          * A defensive copy of {@code tags} is used internally.
          */
-        public void setTags(Set<Tag> tags) {
-            this.tags = (tags != null) ? new HashSet<>(tags) : null;
+        public void setTags(Tags tags) {
+            this.tags = tags;
         }
 
         /**
          * Returns an unmodifiable tag set, which throws {@code UnsupportedOperationException}
          * if modification is attempted.
          * Returns {@code Optional#empty()} if {@code tags} is null.
          */
-        public Optional<Set<Tag>> getTags() {
-            return (tags != null) ? Optional.of(Collections.unmodifiableSet(tags)) : Optional.empty();
+        public Optional<Tags> getTags() {
+            return Optional.ofNullable(tags);
         }
 
         @Override

src/main/java/seedu/address/logic/parser/AddCommandParser.java

@@ -7,17 +7,16 @@
 import static seedu.address.logic.parser.CliSyntax.PREFIX_PHONE;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_TAG;
 
-import java.util.Set;
 import java.util.stream.Stream;
 
 import seedu.address.logic.commands.AddCommand;
 import seedu.address.logic.parser.exceptions.ParseException;
-import seedu.address.model.person.Address;
-import seedu.address.model.person.Email;
-import seedu.address.model.person.Name;
 import seedu.address.model.person.Person;
-import seedu.address.model.person.Phone;
-import seedu.address.model.tag.Tag;
+import seedu.address.model.person.fields.mandatory.Address;
+import seedu.address.model.person.fields.mandatory.Email;
+import seedu.address.model.person.fields.mandatory.Name;
+import seedu.address.model.person.fields.mandatory.Phone;
+import seedu.address.model.person.fields.optional.Tags;
 
 /**
  * Parses input arguments and creates a new AddCommand object
@@ -43,9 +42,9 @@ public AddCommand parse(String args) throws ParseException {
         Phone phone = ParserUtil.parsePhone(argMultimap.getValue(PREFIX_PHONE).get());
         Email email = ParserUtil.parseEmail(argMultimap.getValue(PREFIX_EMAIL).get());
         Address address = ParserUtil.parseAddress(argMultimap.getValue(PREFIX_ADDRESS).get());
-        Set<Tag> tagList = ParserUtil.parseTags(argMultimap.getAllValues(PREFIX_TAG));
+        Tags tags = ParserUtil.parseTags(argMultimap.getAllValues(PREFIX_TAG));
 
-        Person person = new Person(name, phone, email, address, tagList);
+        Person person = new Person(name, phone, email, address, tags);
 
         return new AddCommand(person);
     }

src/main/java/seedu/address/logic/parser/EditCommandParser.java

@@ -8,16 +8,10 @@
 import static seedu.address.logic.parser.CliSyntax.PREFIX_PHONE;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_TAG;
 
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Optional;
-import java.util.Set;
-
 import seedu.address.commons.core.index.Index;
 import seedu.address.logic.commands.EditCommand;
 import seedu.address.logic.commands.EditCommand.EditPersonDescriptor;
 import seedu.address.logic.parser.exceptions.ParseException;
-import seedu.address.model.tag.Tag;
 
 /**
  * Parses input arguments and creates a new EditCommand object
@@ -58,7 +52,9 @@ public EditCommand parse(String args) throws ParseException {
         if (argMultimap.getValue(PREFIX_ADDRESS).isPresent()) {
             editPersonDescriptor.setAddress(ParserUtil.parseAddress(argMultimap.getValue(PREFIX_ADDRESS).get()));
         }
-        parseTagsForEdit(argMultimap.getAllValues(PREFIX_TAG)).ifPresent(editPersonDescriptor::setTags);
+        if (argMultimap.getValue(PREFIX_TAG).isPresent()) {
+            editPersonDescriptor.setTags(ParserUtil.parseTags(argMultimap.getAllValues(PREFIX_TAG)));
+        }
 
         if (!editPersonDescriptor.isAnyFieldEdited()) {
             throw new ParseException(EditCommand.MESSAGE_NOT_EDITED);
@@ -67,19 +63,4 @@ public EditCommand parse(String args) throws ParseException {
         return new EditCommand(index, editPersonDescriptor);
     }
 
-    /**
-     * Parses {@code Collection<String> tags} into a {@code Set<Tag>} if {@code tags} is non-empty.
-     * If {@code tags} contain only one element which is an empty string, it will be parsed into a
-     * {@code Set<Tag>} containing zero tags.
-     */
-    private Optional<Set<Tag>> parseTagsForEdit(Collection<String> tags) throws ParseException {
-        assert tags != null;
-
-        if (tags.isEmpty()) {
-            return Optional.empty();
-        }
-        Collection<String> tagSet = tags.size() == 1 && tags.contains("") ? Collections.emptySet() : tags;
-        return Optional.of(ParserUtil.parseTags(tagSet));
-    }
-
 }

src/main/java/seedu/address/logic/parser/ParserUtil.java

@@ -3,16 +3,15 @@
 import static java.util.Objects.requireNonNull;
 
 import java.util.Collection;
-import java.util.HashSet;
-import java.util.Set;
 
 import seedu.address.commons.core.index.Index;
 import seedu.address.commons.util.StringUtil;
 import seedu.address.logic.parser.exceptions.ParseException;
-import seedu.address.model.person.Address;
-import seedu.address.model.person.Email;
-import seedu.address.model.person.Name;
-import seedu.address.model.person.Phone;
+import seedu.address.model.person.fields.mandatory.Address;
+import seedu.address.model.person.fields.mandatory.Email;
+import seedu.address.model.person.fields.mandatory.Name;
+import seedu.address.model.person.fields.mandatory.Phone;
+import seedu.address.model.person.fields.optional.Tags;
 import seedu.address.model.tag.Tag;
 
 /**
@@ -113,12 +112,8 @@ public static Tag parseTag(String tag) throws ParseException {
     /**
      * Parses {@code Collection<String> tags} into a {@code Set<Tag>}.
      */
-    public static Set<Tag> parseTags(Collection<String> tags) throws ParseException {
+    public static Tags parseTags(Collection<String> tags) throws ParseException {
         requireNonNull(tags);
-        final Set<Tag> tagSet = new HashSet<>();
-        for (String tagName : tags) {
-            tagSet.add(parseTag(tagName));
-        }
-        return tagSet;
+        return new Tags(tags.toArray(new String[0]));
     }
 }

src/main/java/seedu/address/model/person/Person.java

@@ -2,17 +2,17 @@
 
 import static seedu.address.commons.util.CollectionUtil.requireAllNonNull;
 
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.List;
 import java.util.Objects;
-import java.util.Set;
 
 import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonProperty;
 
 import seedu.address.commons.util.ToStringBuilder;
-import seedu.address.model.tag.Tag;
+import seedu.address.model.person.fields.mandatory.Address;
+import seedu.address.model.person.fields.mandatory.Email;
+import seedu.address.model.person.fields.mandatory.Name;
+import seedu.address.model.person.fields.mandatory.Phone;
+import seedu.address.model.person.fields.optional.Tags;
 
 /**
  * Represents a Person in the address book.
@@ -27,33 +27,29 @@ public class Person {
 
     // Data fields
     private final Address address;
-    private final Set<Tag> tags = new HashSet<>();
+    private final Tags tags;
 
     /**
      * Every field must be present and not null.
      */
-    public Person(Name name, Phone phone, Email email, Address address, Set<Tag> tags) {
+    public Person(Name name, Phone phone, Email email, Address address, Tags tags) {
         requireAllNonNull(name, phone, email, address, tags);
         this.name = name;
         this.phone = phone;
         this.email = email;
         this.address = address;
-        this.tags.addAll(tags);
+        this.tags = tags;
     }
 
     @JsonCreator
     private Person(@JsonProperty("name") String name, @JsonProperty("phone") String phone,
                    @JsonProperty("email") String email, @JsonProperty("address") String address,
-                   @JsonProperty("tags") List<String> tagNames) {
+                   @JsonProperty("tags") String[] tagNames) {
         this.name = new Name(name);
         this.phone = new Phone(phone);
         this.email = new Email(email);
         this.address = new Address(address);
-        if (tagNames != null) {
-            for (String tagName : tagNames) {
-                this.tags.add(new Tag(tagName));
-            }
-        }
+        this.tags = new Tags(tagNames);
     }
 
     public Name getName() {
@@ -72,12 +68,8 @@ public Address getAddress() {
         return address;
     }
 
-    /**
-     * Returns an immutable tag set, which throws {@code UnsupportedOperationException}
-     * if modification is attempted.
-     */
-    public Set<Tag> getTags() {
-        return Collections.unmodifiableSet(tags);
+    public Tags getTags() {
+        return tags;
     }
 
     /**

src/main/java/seedu/address/model/person/fields/Field.java

@@ -1,2 +1,8 @@
-package seedu.address.model.person.fields;public interface Field {
+package seedu.address.model.person.fields;
+
+/**
+ * Represents an interface for Person fields.
+ */
+public interface Field {
+
 }

src/main/java/seedu/address/model/person/fields/mandatory/Address.java

@@ -1,4 +1,4 @@
-package seedu.address.model.person;
+package seedu.address.model.person.fields.mandatory;
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.commons.util.AppUtil.checkArgument;
@@ -9,7 +9,7 @@
  * Represents a Person's address in the address book.
  * Guarantees: immutable; is valid as declared in {@link #isValidAddress(String)}
  */
-public class Address {
+public class Address implements MandatoryField {
 
     public static final String MESSAGE_CONSTRAINTS = "Addresses can take any values, and it should not be blank";
 

src/main/java/seedu/address/model/person/fields/mandatory/Email.java

@@ -1,4 +1,4 @@
-package seedu.address.model.person;
+package seedu.address.model.person.fields.mandatory;
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.commons.util.AppUtil.checkArgument;
@@ -9,7 +9,7 @@
  * Represents a Person's email in the address book.
  * Guarantees: immutable; is valid as declared in {@link #isValidEmail(String)}
  */
-public class Email {
+public class Email implements MandatoryField {
 
     private static final String SPECIAL_CHARACTERS = "+_.-";
     public static final String MESSAGE_CONSTRAINTS = "Emails should be of the format local-part@domain "

src/main/java/seedu/address/model/person/fields/mandatory/MandatoryField.java

@@ -1,2 +1,10 @@
-package seedu.address.model.person.fields.mandatory;public interface MandatoryField {
+package seedu.address.model.person.fields.mandatory;
+
+import seedu.address.model.person.fields.Field;
+
+/**
+ * Represents an interface for mandatory Person fields.
+ */
+public interface MandatoryField extends Field {
+
 }

src/main/java/seedu/address/model/person/fields/mandatory/Name.java

@@ -1,4 +1,4 @@
-package seedu.address.model.person;
+package seedu.address.model.person.fields.mandatory;
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.commons.util.AppUtil.checkArgument;
@@ -9,7 +9,7 @@
  * Represents a Person's name in the address book.
  * Guarantees: immutable; is valid as declared in {@link #isValidName(String)}
  */
-public class Name {
+public class Name implements MandatoryField {
 
     public static final String MESSAGE_CONSTRAINTS =
             "Names should only contain alphanumeric characters and spaces, and it should not be blank";

src/main/java/seedu/address/model/person/fields/mandatory/Phone.java

@@ -1,4 +1,4 @@
-package seedu.address.model.person;
+package seedu.address.model.person.fields.mandatory;
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.commons.util.AppUtil.checkArgument;
@@ -9,7 +9,7 @@
  * Represents a Person's phone number in the address book.
  * Guarantees: immutable; is valid as declared in {@link #isValidPhone(String)}
  */
-public class Phone {
+public class Phone implements MandatoryField {
 
     public static final String MESSAGE_CONSTRAINTS =
             "Phone numbers should only contain numbers, and it should be at least 3 digits long";

src/main/java/seedu/address/model/person/fields/optional/OptionalField.java

@@ -1,2 +1,7 @@
-package seedu.address.model.person.fields.optional;public interface OptionalField {
+package seedu.address.model.person.fields.optional;
+
+/**
+ * Represents an interface for optional Person fields
+ */
+public interface OptionalField {
 }