From 2c8f09e35dd4c1d5a38e94bba24b115fd75987c7 Mon Sep 17 00:00:00 2001
From: Maksym Musiienko <maxymvm@gmail.com>
Date: Wed, 8 Nov 2023 21:55:39 +0200
Subject: [PATCH] did all expected changes

---
 src/main/java/core/basesyntax/ArrayList.java | 58 +++++++++-----------
 1 file changed, 25 insertions(+), 33 deletions(-)

diff --git a/src/main/java/core/basesyntax/ArrayList.java b/src/main/java/core/basesyntax/ArrayList.java
index f062f2f5e..dc56836f8 100644
--- a/src/main/java/core/basesyntax/ArrayList.java
+++ b/src/main/java/core/basesyntax/ArrayList.java
@@ -5,11 +5,11 @@
 public class ArrayList<T> implements List<T> {
     private static final int DEFAULT_CAPACITY = 10;
     private static final double RESIZE_COEFFICIENT = 1.5;
-    private Object[] elements;
+    private T[] elements;
     private int size;
 
     public ArrayList() {
-        this.elements = new Object[DEFAULT_CAPACITY];
+        this.elements = (T[]) new Object[DEFAULT_CAPACITY];
     }
 
     @Override
@@ -20,11 +20,7 @@ public void add(T value) {
 
     @Override
     public void add(T value, int index) {
-        if (index < 0 || index > size) {
-            throw new ArrayListIndexOutOfBoundsException("Index outed of bounds, Index: " + index
-                    + ", Size: "
-                    + size);
-        }
+        checkAddBounds(index);
         ensureCapacity();
         System.arraycopy(elements, index, elements, index + 1, size - index);
         elements[index] = value;
@@ -40,31 +36,19 @@ public void addAll(List<T> list) {
 
     @Override
     public T get(int index) {
-        if (index < 0 || index >= size) {
-            throw new ArrayListIndexOutOfBoundsException("Index outed of bounds, Index: " + index
-                    + ", Size: "
-                    + size);
-        }
+        checkBounds(index);
         return (T) elements[index];
     }
 
     @Override
     public void set(T value, int index) {
-        if (index < 0 || index >= size) {
-            throw new ArrayListIndexOutOfBoundsException("Index outed of bounds, Index: " + index
-                    + ", Size: "
-                    + size);
-        }
+        checkBounds(index);
         elements[index] = value;
     }
 
     @Override
     public T remove(int index) {
-        if (index < 0 || index >= size) {
-            throw new ArrayListIndexOutOfBoundsException("Index outed of bounds, Index: " + index
-                    + ", Size: "
-                    + size);
-        }
+        checkBounds(index);
         T removedValue = (T) elements[index];
         System.arraycopy(elements, index + 1, elements, index, size - index - 1);
         elements[--size] = null;
@@ -73,17 +57,9 @@ public T remove(int index) {
 
     @Override
     public T remove(T element) {
-        if (element == null) {
-            for (int i = 0; i < size; i++) {
-                if (elements[i] == null) {
-                    return remove(i);
-                }
-            }
-            throw new NoSuchElementException("Element not found");
-        }
-
         for (int i = 0; i < size; i++) {
-            if (element.equals(elements[i])) {
+            if ((element == null && elements[i] == null)
+                    || (element != null && element.equals(elements[i]))) {
                 return remove(i);
             }
         }
@@ -102,7 +78,7 @@ public boolean isEmpty() {
 
     private void resize() {
         int newCapacity = (int) (elements.length * RESIZE_COEFFICIENT);
-        Object[] newElements = new Object[newCapacity];
+        T[] newElements = (T[]) new Object[newCapacity];
         System.arraycopy(elements, 0, newElements, 0, size);
         elements = newElements;
     }
@@ -112,4 +88,20 @@ private void ensureCapacity() {
             resize();
         }
     }
+
+    private void checkBounds(int index) {
+        if (index < 0 || index >= size) {
+            throw new ArrayListIndexOutOfBoundsException("Index outed of bounds, Index: " + index
+                    + ", Size: "
+                    + size);
+        }
+    }
+
+    private void checkAddBounds(int index) {
+        if (index < 0 || index > size) {
+            throw new ArrayListIndexOutOfBoundsException("Index outed of bounds, Index: " + index
+                    + ", Size: "
+                    + size);
+        }
+    }
 }