diff --git a/src/main/java/core/basesyntax/ArrayList.java b/src/main/java/core/basesyntax/ArrayList.java index 8d6477943..0906b9b34 100644 --- a/src/main/java/core/basesyntax/ArrayList.java +++ b/src/main/java/core/basesyntax/ArrayList.java @@ -1,48 +1,107 @@ package core.basesyntax; +import java.util.NoSuchElementException; + public class ArrayList implements List { + private static final int DEFAULT_SIZE = 10; + private static final double GROW_MULTIPLIER = 1.5; + private int size; + private Object[] elementData; + + public ArrayList() { + elementData = new Object[DEFAULT_SIZE]; + + } + + public void checkCapacity() { + if (size == elementData.length) { + int newSize = (int)(elementData.length * GROW_MULTIPLIER); + Object[] newArray = new Object[newSize]; + System.arraycopy(elementData, 0, newArray, 0, size); + elementData = newArray; + } + } + @Override public void add(T value) { + checkCapacity(); + elementData[size++] = value; } @Override public void add(T value, int index) { + checkIndexForSet(index); + checkCapacity(); + System.arraycopy(elementData, index, elementData, index + 1, size - index); + elementData[index] = value; + size++; } + public void checkIndexForSet(int index) { + if (index < 0 || index > size) { + throw new ArrayListIndexOutOfBoundsException("Index: " + index + ", Size: " + size); + } + } + @Override public void addAll(List list) { + for (int i = 0; i < list.size(); i++) { + add(list.get(i)); + + } } @Override public T get(int index) { - return null; + checkIndex(index); + return (T) elementData[index]; + + } + + public void checkIndex(int index) { + if (index < 0 || index >= size) { + throw new ArrayListIndexOutOfBoundsException("Index: " + index + ", Size: " + size); + } } @Override public void set(T value, int index) { + checkIndex(index); + elementData[index] = value; } @Override public T remove(int index) { - return null; + checkIndex(index); + T removedValue = (T) elementData[index]; + System.arraycopy(elementData, index + 1, elementData, index, size - index - 1); + elementData[--size] = null; + return removedValue; } @Override public T remove(T element) { - return null; + for (int i = 0; i < size; i++) { + if ((element == null && elementData[i] == null) + || (element != null && element.equals(elementData[i]))) { + return remove(i); + } + + } + throw new NoSuchElementException("This element doesn't exist in Array :" + element); } @Override public int size() { - return 0; + return size; } @Override public boolean isEmpty() { - return false; + return size() == 0; } }