diff --git a/src/main/java/core/basesyntax/ArrayList.java b/src/main/java/core/basesyntax/ArrayList.java index 8d6477943..344eb6c19 100644 --- a/src/main/java/core/basesyntax/ArrayList.java +++ b/src/main/java/core/basesyntax/ArrayList.java @@ -1,48 +1,116 @@ package core.basesyntax; +import java.util.NoSuchElementException; + public class ArrayList implements List { + + private static final int DEFAULT_CAPACITY = 10; + + private Object[] elements; + + private int size; + + public ArrayList() { + elements = new Object[DEFAULT_CAPACITY]; + } + @Override public void add(T value) { - + growIfFull(); + elements[size] = value; + size++; } @Override public void add(T value, int index) { + checkIndexForAdd(index); + growIfFull(); + System.arraycopy(elements, index, elements, index + 1, size - index); + + elements[index] = value; + size++; } @Override public void addAll(List list) { - + for (int i = 0; i < list.size(); i++) { + add(list.get(i)); + } } @Override + @SuppressWarnings("unchecked") public T get(int index) { - return null; + checkIndex(index); + return (T) elements[index]; } @Override public void set(T value, int index) { - + checkIndex(index); + elements[index] = value; } @Override + @SuppressWarnings("unchecked") public T remove(int index) { - return null; + checkIndex(index); + final T removed = (T) elements[index]; + System.arraycopy(elements, index + 1, elements, index, size - index - 1); + + elements[size - 1] = null; + size--; + return removed; } @Override + @SuppressWarnings("unchecked") public T remove(T element) { - return null; + for (int i = 0; i < size; i++) { + T current = (T) elements[i]; + + if (current == element + || current != null && current.equals(element)) { + return remove(i); + } + } + throw new NoSuchElementException("Element not found: " + element); } @Override public int size() { - return 0; + return size; } @Override public boolean isEmpty() { - return false; + return size == 0; + } + + private void growIfFull() { + if (size == elements.length) { + int newCapacity = elements.length + elements.length / 2; + Object[] newElements = new Object[newCapacity]; + + System.arraycopy(elements, 0, newElements, 0, size); + elements = newElements; + } + } + + private void checkIndex(int index) { + if (index < 0 || index >= size) { + throw new ArrayListIndexOutOfBoundsException( + "Index: " + index + ", Size: " + size + ); + } + } + + private void checkIndexForAdd(int index) { + if (index < 0 || index > size) { + throw new ArrayListIndexOutOfBoundsException( + "Index: " + index + ", Size: " + size + ); + } } }