diff --git a/src/main/java/cm/soungui/guacamole/ext/wallix/sync/db/Entity.java b/src/main/java/cm/soungui/guacamole/ext/wallix/sync/db/Entity.java
index eab0f76..603f577 100644
--- a/src/main/java/cm/soungui/guacamole/ext/wallix/sync/db/Entity.java
+++ b/src/main/java/cm/soungui/guacamole/ext/wallix/sync/db/Entity.java
@@ -8,13 +8,16 @@ public class Entity {
 	
 	private String name;
 	
-	public EntityType type;
+	private EntityType type;
 
 	public int getId() {
 		return id;
 	}
 
 	public void setId(int id) {
+		if (id < 0) {
+			throw new IllegalArgumentException("Id can't be null");
+		}
 		this.id = id;
 	}
 
@@ -33,5 +36,27 @@ public class Entity {
 	public void setType(EntityType type) {
 		this.type = type;
 	}
+	
+	@Override
+	public int hashCode() {
+		return getName() == null ? super.hashCode() : getName().hashCode();
+	}
+	
+	@Override
+	public boolean equals(Object obj) {
+		if(super.equals(obj)) {
+			return true;
+		}
+		if (obj instanceof Entity) {
+			Entity entity = (Entity) obj;
+			if (getType() != entity.getType()) {
+				return false;
+			}
+			
+			boolean namesAreTheSame = entity.getName() != null && getName() != null && getName().equals(entity.getName());
+			return namesAreTheSame;
+		}
+		return false;
+	}
 
 }
diff --git a/src/test/java/cm/soungui/guacamole/ext/wallix/sync/db/test/TestEntity.java b/src/test/java/cm/soungui/guacamole/ext/wallix/sync/db/test/TestEntity.java
new file mode 100644
index 0000000..004a4df
--- /dev/null
+++ b/src/test/java/cm/soungui/guacamole/ext/wallix/sync/db/test/TestEntity.java
@@ -0,0 +1,84 @@
+package cm.soungui.guacamole.ext.wallix.sync.db.test;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import cm.soungui.guacamole.ext.wallix.sync.db.Entity;
+import cm.soungui.guacamole.ext.wallix.sync.db.User;
+import cm.soungui.guacamole.ext.wallix.sync.db.UserGroup;
+import junit.framework.TestCase;
+
+public class TestEntity extends TestCase {
+
+	public final void testEqualsSameObject() {
+		User user1 = new User();
+		
+		assertEquals(user1, user1);
+	}
+
+	public final void testEqualsDifferentObject() {
+		User user1 = new User();
+		User user2 = new User();
+		
+		assertNotSame(user1, user2);
+	}
+
+	public final void testEqualsSameName() {
+		User user1 = new User();
+		user1.setName("name");
+		User user2 = new User();
+		user2.setName("name");
+		
+		assertEquals(user1, user2);
+	}
+
+	public final void testEqualsDifferentName() {
+		User user1 = new User();
+		user1.setName("name");
+		User user2 = new User();
+		user2.setName("anotherName");
+		
+		assertNotSame(user1, user2);
+	}
+
+	public final void testEqualsDifferentType() {
+		User user1 = new User();
+		user1.setName("name");
+		UserGroup group = new UserGroup();
+		group.setName("name");
+		
+		assertNotSame(user1, group);
+	}
+	
+	public final void testAddDifferentNames() {
+		Set<Entity> entities = new HashSet<>();
+		
+		User user1 = new User();
+		user1.setName("name");
+		User user2 = new User();
+		user2.setName("anotherName");
+		
+		entities.add(user1);
+		entities.add(user2);
+		
+		assert(entities.size()==2);
+	}
+	
+	public final void testAddSameName() {
+		Set<Entity> entities = new HashSet<>();
+		
+		User user1 = new User();
+		user1.setName("name");
+		User user2 = new User();
+		user2.setName("name");
+		
+		entities.add(user1);
+		
+		assert(entities.contains(user2));
+		
+		entities.add(user2);
+//		
+		assert(entities.size()==1);
+	}
+
+}