[W8.6b][W15-B4]Muhammad Nur Kamal

src/seedu/addressbook/data/AddressBook.java

@@ -1,5 +1,6 @@
 package seedu.addressbook.data;
 
+import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
@@ -11,6 +12,7 @@
 import seedu.addressbook.data.person.UniquePersonList.DuplicatePersonException;
 import seedu.addressbook.data.person.UniquePersonList.PersonNotFoundException;
 import seedu.addressbook.data.tag.Tag;
+import seedu.addressbook.data.tag.Tagging;
 import seedu.addressbook.data.tag.UniqueTagList;
 
 /**
@@ -24,13 +26,15 @@ public class AddressBook {
 
     private final UniquePersonList allPersons;
     private final UniqueTagList allTags; // can contain tags not attached to any person
+    private final ArrayList<Tagging> taggings;
 
     /**
      * Creates an empty address book.
      */
     public AddressBook() {
         allPersons = new UniquePersonList();
         allTags = new UniqueTagList();
+        taggings = new ArrayList<>();
     }
 
     /**
@@ -46,6 +50,7 @@ public AddressBook(UniquePersonList persons, UniqueTagList tags) {
         for (Person p : allPersons) {
             syncTagsWithMasterList(p);
         }
+        taggings = new ArrayList<>();
     }
 
     /**

src/seedu/addressbook/data/tag/Tagging.java

@@ -0,0 +1,30 @@
+package seedu.addressbook.data.tag;
+
+import seedu.addressbook.data.person.Person;
+
+/**
+ * Represents an addition or removal of tag in the address book.
+ */
+public class Tagging {
+    private Person person;
+    private Tag tag;
+    private boolean isAddition;
+
+    public Tagging(Person person, Tag tag, boolean isAddition) {
+        this.person = person;
+        this.tag = tag;
+        this.isAddition = isAddition;
+    }
+
+    public Person getPerson() {
+        return person;
+    }
+
+    public Tag getTag() {
+        return tag;
+    }
+
+    public boolean isAddition() {
+        return isAddition;
+    }
+}