diff --git a/pom.xml b/pom.xml
index 979cb1f..31d4a33 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,6 +5,28 @@
     <artifactId>interview</artifactId>
     <packaging>jar</packaging>
     <version>1.0-SNAPSHOT</version>
-    <name>interview</name>
-    <url>http://maven.apache.org</url>
-</project>
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.4</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>compile</scope>
+        </dependency>
+        <dependency>
+            <groupId>log4j</groupId>
+            <artifactId>log4j</artifactId>
+            <version>1.2.17</version>
+        </dependency>
+    </dependencies>
+    <properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
+    </properties>
+
+</project>
\ No newline at end of file
diff --git a/src/main/java/com/zhokhov/interview/data/ArrayList.java b/src/main/java/com/zhokhov/interview/data/ArrayList.java
index d27c621..c3610e7 100644
--- a/src/main/java/com/zhokhov/interview/data/ArrayList.java
+++ b/src/main/java/com/zhokhov/interview/data/ArrayList.java
@@ -9,14 +9,18 @@
  */
 package com.zhokhov.interview.data;
 
+import java.util.logging.Logger;
+
 /**
  * @author <a href='mailto:alexey@zhokhov.com'>Alexey Zhokhov</a>
  */
+
 public class ArrayList {
 
     private static final int SIZE_FACTOR = 5;
 
-    private Object data[];
+    private static final Logger logger = Logger.getLogger(ArrayList.class.getName());
+    private Object[] data;
 
     private int index;
 
@@ -29,7 +33,6 @@ public ArrayList() {
 
     public void add(Object item) {
         System.out.println("index:" + this.index + "size:" + this.size + "data size:" + this.data.length);
-
         if (this.index == this.size - 1) {
             //we need to increase the size of data[]
             increaseSizeAndReallocate();
@@ -43,46 +46,43 @@ private void increaseSizeAndReallocate() {
         this.size = this.size + SIZE_FACTOR;
 
         // TODO: Arrays.copyOf()
-        Object newData[] = new Object[this.size];
+        Object[] newData = new Object[this.size];
 
         // TODO: System.arraycopy(data, 0, newData, 0, data.length);
-        for (int i = 0; i < data.length; i++) {
-            newData[i] = data[i];
-        }
+        System.arraycopy(data, 0, newData, 0, data.length);
 
         this.data = newData;
 
-        System.out.println("***index:" + this.index + "size:" + this.size + "data size:" + this.data.length);
+        logger.info("***index:" + this.index + "size:" + this.size + "data size:" + this.data.length);
     }
 
-    public Object get(int index) throws Exception {
+    public Object get(int index) {
         if (index > this.index - 1) {
-            throw new Exception("ArrayIndexOutOfBound");
+            throw new IllegalStateException("ArrayIndexOutOfBound");
         }
         if (index < 0) {
-            throw new Exception("Negative Value");
+            throw new IllegalStateException("Negative Value");
         }
 
         return this.data[index];
     }
 
-    public void remove(int removeIndex) throws Exception {
+    public void remove(int removeIndex) {
         if (removeIndex > this.index - 1) {
-            throw new Exception("ArrayIndexOutOfBound");
+            throw new IllegalStateException("ArrayIndexOutOfBound");
         }
         if (removeIndex < 0) {
-            throw new Exception("Negative Value");
+            throw new IllegalStateException("Negative Value");
         }
-        System.out.println("Object getting removed:" + this.data[removeIndex]);
+        logger.fine("Object getting removed: " + this.data[removeIndex]);
 
-        for (int i = removeIndex; i < this.data.length - 1; i++) {
-            data[i] = data[i + 1];
-        }
+        if (this.data.length - 1 - removeIndex >= 0)
+            System.arraycopy(data, removeIndex + 1, data, removeIndex, this.data.length - 1 - removeIndex);
 
         this.index--;
     }
 
-    public static void main(String[] args) throws Exception {
+    public static void main(String[] args) {
         ArrayList mal = new ArrayList();
         mal.add("1");
         mal.add("2");
@@ -98,7 +98,7 @@ public static void main(String[] args) throws Exception {
         // remove by index
         mal.remove(5);
 
-        System.out.println(mal.get(7));
+        logger.info((String) mal.get(7));
     }
 
 }
\ No newline at end of file
diff --git a/src/test/java/sorting/BubbleSortTest.java b/src/test/java/sorting/BubbleSortTest.java
new file mode 100644
index 0000000..13e2f3f
--- /dev/null
+++ b/src/test/java/sorting/BubbleSortTest.java
@@ -0,0 +1,38 @@
+package sorting;
+
+import com.zhokhov.interview.sorting.BubbleSort;
+import com.zhokhov.interview.util.Console;
+import junit.framework.TestCase;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+
+@RunWith(JUnit4.class)
+public class BubbleSortTest extends TestCase {
+
+
+    private static int[] array;
+
+
+    @Test
+    public void bubbleSortIntegerArray(){
+        array = new int[]{12, 2, 8, 5, 1, 6, 4, 15};
+        BubbleSort bubbleSort = new BubbleSort();
+        bubbleSort.sort(array);
+        Console.__red("Index 1 is value in this array => " + array[1]);
+        assertEquals(2, array[1]);
+    }
+
+    @Test
+    public void checkLengthAfterUsingBubbleSort(){
+        array = new int[]{12, 2, 8, 5, 1, 6, 4, 15};
+        int lengthBeforeSort = array.length;
+        BubbleSort bubbleSort = new BubbleSort();
+        bubbleSort.sort(array);
+        int lengthAfterSort = array.length;
+        assertEquals(lengthBeforeSort, lengthAfterSort);
+    }
+
+
+}
\ No newline at end of file