[W5][W13-1]Yong Xin Shen

src/seedu/addressbook/data/person/Person.java

@@ -1,5 +1,6 @@
 package seedu.addressbook.data.person;
 
+import java.time.Instant;
 import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
@@ -17,6 +18,8 @@ public class Person implements ReadOnlyPerson {
     private Email email;
     private Address address;
 
+    private Instant timeAdded;
+
     private final Set<Tag> tags = new HashSet<>();
 
     /**
@@ -28,6 +31,8 @@ public Person(Name name, Phone phone, Email email, Address address, Set<Tag> tag
         this.email = email;
         this.address = address;
         this.tags.addAll(tags);
+
+        this.timeAdded = Instant.now();
     }
 
     /**
@@ -57,6 +62,11 @@ public Address getAddress() {
         return address;
     }
 
+    @Override
+    public Instant getTimeAdded() {
+        return timeAdded;
+    }
+
     @Override
     public Set<Tag> getTags() {
         return new HashSet<>(tags);

src/seedu/addressbook/data/person/ReadOnlyPerson.java

@@ -1,5 +1,6 @@
 package seedu.addressbook.data.person;
 
+import java.time.Instant;
 import java.util.Set;
 
 import seedu.addressbook.data.tag.Tag;
@@ -14,6 +15,7 @@ public interface ReadOnlyPerson {
     Phone getPhone();
     Email getEmail();
     Address getAddress();
+    Instant getTimeAdded();
 
     /**
      * Returns a new TagSet that is a deep copy of the internal TagSet,
@@ -89,6 +91,9 @@ default String getAsTextHidePrivate() {
         if (!getAddress().isPrivate()) {
             builder.append(" Address: ").append(getAddress());
         }
+
+        builder.append(" DateTime added: ").append(getTimeAdded());
+
         builder.append(" Tags: ");
         for (Tag tag : getTags()) {
             builder.append(tag);

test/java/seedu/addressbook/commands/AddCommandTest.java

@@ -112,6 +112,7 @@ public void addCommand_validData_correctlyConstructed() throws Exception {
         assertTrue(p.getAddress().isPrivate());
         boolean isTagListEmpty = !p.getTags().iterator().hasNext();
         assertTrue(isTagListEmpty);
+        assertFalse(p.getTimeAdded().toString().isEmpty());
     }
 
     @Test