Add ArrayList

src/main/java/de/szut/MyArrayList.java

@@ -0,0 +1,55 @@
+package de.szut;
+
+import java.util.Arrays;
+
+public class MyArrayList {
+
+    private static final int INITIAL_CAPACITY = 10;
+
+    private int[] array;
+    private int size;
+
+    public MyArrayList() {
+        this.array = new int[INITIAL_CAPACITY];
+        this.size = 0;
+    }
+
+    public int size() {
+        return size;
+    }
+
+    public boolean add(int value) {
+        ensureCapacity();
+        array[size++] = value;
+        return true;
+    }
+
+    public void remove(int index) {
+        if (index < 0 || index >= size) {
+            throw new RuntimeException("Dieser Index existiert nicht!");
+        }
+
+        for (int i = index; i < size - 1; i++) {
+            array[i] = array[i + 1];
+        }
+
+        array[--size] = 0;
+    }
+
+
+    public boolean contains(int value) {
+        for (int i = 0; i < size; i++) {
+            if (array[i] == value) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private void ensureCapacity() {
+        if (size == array.length) {
+            int newCapacity = array.length + INITIAL_CAPACITY;
+            array = Arrays.copyOf(array, newCapacity);
+        }
+    }
+}