diff --git a/unitofwork/pom.xml b/unitofwork/pom.xml
index e790c8168..38b0e1b42 100644
--- a/unitofwork/pom.xml
+++ b/unitofwork/pom.xml
@@ -10,6 +10,16 @@
     <modelVersion>4.0.0</modelVersion>
 
     <artifactId>unit-of-work</artifactId>
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+        </dependency>
+    </dependencies>
 
 
 </project>
\ No newline at end of file
diff --git a/unitofwork/src/main/java/com/iluwatar/unitofwork/IUnitOfWork.java b/unitofwork/src/main/java/com/iluwatar/unitofwork/IUnitOfWork.java
index 9fb2e362b..d63a6d8c7 100644
--- a/unitofwork/src/main/java/com/iluwatar/unitofwork/IUnitOfWork.java
+++ b/unitofwork/src/main/java/com/iluwatar/unitofwork/IUnitOfWork.java
@@ -28,12 +28,16 @@ package com.iluwatar.unitofwork;
  * @param <T> Any generic entity
  */
 public interface IUnitOfWork<T> {
-  public void registerNew(T entity);
+  String INSERT = "INSERT";
+  String DELETE = "DELETE";
+  String MODIFY = "MODIFY";
 
-  public void registerModified(T entity);
+  void registerNew(T entity);
 
-  public void registerDeleted(T entity);
+  void registerModified(T entity);
 
-  public void commit();
+  void registerDeleted(T entity);
+
+  void commit();
 
 }
\ No newline at end of file
diff --git a/unitofwork/src/main/java/com/iluwatar/unitofwork/Student.java b/unitofwork/src/main/java/com/iluwatar/unitofwork/Student.java
index fa80089f2..9b77717ec 100644
--- a/unitofwork/src/main/java/com/iluwatar/unitofwork/Student.java
+++ b/unitofwork/src/main/java/com/iluwatar/unitofwork/Student.java
@@ -42,5 +42,5 @@ public class Student {
     this.name = name;
     this.address = address;
   }
-  
+
 }
diff --git a/unitofwork/src/main/java/com/iluwatar/unitofwork/StudentDatabase.java b/unitofwork/src/main/java/com/iluwatar/unitofwork/StudentDatabase.java
new file mode 100644
index 000000000..678fe4026
--- /dev/null
+++ b/unitofwork/src/main/java/com/iluwatar/unitofwork/StudentDatabase.java
@@ -0,0 +1,43 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Piyush Chaudhari
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.iluwatar.unitofwork;
+
+/**
+ * Act as Database for student records.
+ */
+public class StudentDatabase {
+
+  public void insert(Student student) {
+    //Some insert logic to DB
+  }
+
+  public void modify(Student student) {
+    //Some modify logic to DB
+  }
+
+  public void delete(Student student) {
+    //Some delete logic to DB
+  }
+}
diff --git a/unitofwork/src/main/java/com/iluwatar/unitofwork/StudentRepository.java b/unitofwork/src/main/java/com/iluwatar/unitofwork/StudentRepository.java
new file mode 100644
index 000000000..a2cff4ada
--- /dev/null
+++ b/unitofwork/src/main/java/com/iluwatar/unitofwork/StudentRepository.java
@@ -0,0 +1,110 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Piyush Chaudhari
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.iluwatar.unitofwork;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * {@link StudentRepository} Student database repository.
+ * supports unit of work for student data.
+ */
+public class StudentRepository implements IUnitOfWork<Student> {
+  private Map<String, List<Student>> context;
+  private StudentDatabase studentDatabase;
+
+  /**
+   * @param context         set of operations to be perform during commit.
+   * @param studentDatabase Database for student records.
+   */
+  public StudentRepository(Map<String, List<Student>> context, StudentDatabase studentDatabase) {
+    this.context = context;
+    this.studentDatabase = studentDatabase;
+  }
+
+  @Override
+  public void registerNew(Student student) {
+    register(student, IUnitOfWork.INSERT);
+  }
+
+  @Override
+  public void registerModified(Student student) {
+    register(student, IUnitOfWork.MODIFY);
+
+  }
+
+  @Override
+  public void registerDeleted(Student student) {
+    register(student, IUnitOfWork.DELETE);
+  }
+
+  private void register(Student student, String operation) {
+    List<Student> studentsToOperate = context.get(operation);
+    if (studentsToOperate == null) {
+      studentsToOperate = new ArrayList<>();
+    }
+    studentsToOperate.add(student);
+    context.put(operation, studentsToOperate);
+  }
+
+  @Override
+  public void commit() {
+    if (context == null || context.size() == 0) {
+      return;
+    }
+    if (context.containsKey(IUnitOfWork.INSERT)) {
+      commitInsert();
+    }
+
+    if (context.containsKey(IUnitOfWork.MODIFY)) {
+      commitModify();
+    }
+    if (context.containsKey(IUnitOfWork.DELETE)) {
+      commitDelete();
+    }
+  }
+
+  private void commitDelete() {
+    List<Student> deletedStudents = context.get(IUnitOfWork.DELETE);
+    for (Student student : deletedStudents) {
+      studentDatabase.delete(student);
+    }
+  }
+
+  private void commitModify() {
+    List<Student> modifiedStudents = context.get(IUnitOfWork.MODIFY);
+    for (Student student : modifiedStudents) {
+      studentDatabase.modify(student);
+    }
+  }
+
+  private void commitInsert() {
+    List<Student> studentsToBeInserted = context.get(IUnitOfWork.INSERT);
+    for (Student student : studentsToBeInserted) {
+      studentDatabase.insert(student);
+    }
+  }
+}
diff --git a/unitofwork/src/test/java/com/iluwatar/unitofwork/StudentRepositoryTest.java b/unitofwork/src/test/java/com/iluwatar/unitofwork/StudentRepositoryTest.java
new file mode 100644
index 000000000..9a71dcbbc
--- /dev/null
+++ b/unitofwork/src/test/java/com/iluwatar/unitofwork/StudentRepositoryTest.java
@@ -0,0 +1,147 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Piyush Chaudhari
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.iluwatar.unitofwork;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.runners.MockitoJUnitRunner;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.*;
+
+/**
+ * tests {@link StudentRepository}
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class StudentRepositoryTest {
+  private final Student student1 = new Student(1, "Ram", "street 9, cupertino");
+  private final Student student2 = new Student(1, "Sham", "Z bridge, pune");
+
+  private Map<String, List<Student>> context;
+  @Mock
+  private StudentDatabase studentDatabase;
+  private StudentRepository studentRepository;
+
+  @Before
+  public void setUp() throws Exception {
+    context = new HashMap<>();
+    studentRepository = new StudentRepository(context, studentDatabase);
+  }
+
+  @Test
+  public void shouldSaveNewStudentWithoutWritingToDb() throws Exception {
+    studentRepository.registerNew(student1);
+    studentRepository.registerNew(student2);
+
+    assertEquals(2, context.get(IUnitOfWork.INSERT).size());
+    verifyNoMoreInteractions(studentDatabase);
+  }
+
+  @Test
+  public void shouldSaveDeletedStudentWithoutWritingToDb() throws Exception {
+    studentRepository.registerDeleted(student1);
+    studentRepository.registerDeleted(student2);
+
+    assertEquals(2, context.get(IUnitOfWork.DELETE).size());
+    verifyNoMoreInteractions(studentDatabase);
+  }
+
+  @Test
+  public void shouldSaveModifiedStudentWithoutWritingToDb() throws Exception {
+    studentRepository.registerModified(student1);
+    studentRepository.registerModified(student2);
+
+    assertEquals(2, context.get(IUnitOfWork.MODIFY).size());
+    verifyNoMoreInteractions(studentDatabase);
+  }
+
+  @Test
+  public void shouldSaveAllLocalChangesToDb() throws Exception {
+    context.put(IUnitOfWork.INSERT, Collections.singletonList(student1));
+    context.put(IUnitOfWork.MODIFY, Collections.singletonList(student1));
+    context.put(IUnitOfWork.DELETE, Collections.singletonList(student1));
+
+    studentRepository.commit();
+
+    verify(studentDatabase, times(1)).insert(student1);
+    verify(studentDatabase, times(1)).modify(student1);
+    verify(studentDatabase, times(1)).delete(student1);
+  }
+
+  @Test
+  public void shouldNotWriteToDbIfContextIsNull() throws Exception {
+    StudentRepository studentRepository = new StudentRepository(null, studentDatabase);
+
+    studentRepository.commit();
+
+    verifyNoMoreInteractions(studentDatabase);
+  }
+
+  @Test
+  public void shouldNotWriteToDbIfNothingToCommit() throws Exception {
+    StudentRepository studentRepository = new StudentRepository(new HashMap<>(), studentDatabase);
+
+    studentRepository.commit();
+
+    verifyZeroInteractions(studentDatabase);
+  }
+
+  @Test
+  public void shouldNotInsertToDbIfNoRegisteredStudentsToBeCommitted() throws Exception {
+    context.put(IUnitOfWork.MODIFY, Collections.singletonList(student1));
+    context.put(IUnitOfWork.DELETE, Collections.singletonList(student1));
+
+    studentRepository.commit();
+
+    verify(studentDatabase, never()).insert(student1);
+  }
+
+  @Test
+  public void shouldNotModifyToDbIfNotRegisteredStudentsToBeCommitted() throws Exception {
+    context.put(IUnitOfWork.INSERT, Collections.singletonList(student1));
+    context.put(IUnitOfWork.DELETE, Collections.singletonList(student1));
+
+    studentRepository.commit();
+
+    verify(studentDatabase, never()).modify(student1);
+  }
+
+  @Test
+  public void shouldNotDeleteFromDbIfNotRegisteredStudentsToBeCommitted() throws Exception {
+    context.put(IUnitOfWork.INSERT, Collections.singletonList(student1));
+    context.put(IUnitOfWork.MODIFY, Collections.singletonList(student1));
+
+    studentRepository.commit();
+
+    verify(studentDatabase, never()).delete(student1);
+  }
+}
\ No newline at end of file