public class MyarrayList {

//initial size

private static final int DEFAULT = 10;

private int count;

private Object[] arrayList;

public MyarrayList(){

count = 0;

arrayList = new Object[DEFAULT];

}

public void add(Object temp){

if(!addble()){

ensureCapacity(count * 2+ 1);

}

arrayList[count] = temp;

count++;

}

public void add(Object temp, int index){

if(index > count || index < 0){

throw new ArrayIndexOutOfBoundsException( );

}

if(arrayList.length == count){ //if it is full

ensureCapacity(count+ 1);

}

for(int i = count; i > index; i--){

arrayList[i] = arrayList[i - 1];

}

arrayList[index] = temp;

count++;

}

public Object get(int index){

if(index > count || index < 0){

throw new ArrayIndexOutOfBoundsException( );

}

return arrayList[index];

}

public Object set(Object temp, int index){

if(index > count || index < 0){

throw new ArrayIndexOutOfBoundsException( );

}

Object old = arrayList[index];

arrayList[index] = temp;

return old;

}

public Object remove(int index){

if(index > count || index < 0){

throw new ArrayIndexOutOfBoundsException( );

}

Object old = arrayList[index];

for(int i = index; i < count - 1; i++){

arrayList[i] = arrayList[i + 1];

}

count--;

return old;

}

public int size(){

return count;

}

public boolean isEmpty(){

return count == 0;

}

//check if there is enough space to add

public boolean addble(){

return (count < DEFAULT);

}

public void ensureCapacity(int newCapacity){

if(newCapacity < count){

return ;

}

Object[] old = arrayList;

arrayList = new Object[newCapacity];

for(int i = 0; i < old.length; i++){

arrayList[i] = old[i];

}

}

public String toString(){

String result = "";

for(int i = 0; i < count;i++){

result += arrayList[i] + " ";

}

return result;

}

}