package Array;

import Array._ArrayList;

public class ArrayList<T> implements _ArrayList<T> {

private Object[] data;

//数组长度

private int n;

//元素个数

private int count;

public ArrayList(int capacity) {

if (capacity > 0) {

this.data = new Object[capacity];

this.n = capacity;

} else if (capacity == 0){

this.data = new Object[0];

this.n = 0;

} else {

throw new IllegalArgumentException("illegal");

}

}

public ArrayList(T[] array){

if (array == null) {

throw new NullPointerException();

}

this.data = new Object[array.length];

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

this.data[i] = array[i];

}

this.n = array.length;

}

@Override

public boolean isEmpty() {

return false;

}

@Override

public int length() {

return 0;

}

//下标获取元素

@Override

public T get(int index) {

if (index >= 0 && index < this.n) {

return (T)this.data[index];

}

return null;

}

//下标设置元素

@Override

public T set(int index, T content) {

if (index > 0 && index < this.n && content != null) {

T old = (T)this.data[index];

this.data[index] = content;

return old;

}

return null;

}

//下标加元素

@Override

public boolean add(int index, T content) {

if (data == null) {

return false;

}

if (index < 0) {

index = 0;

}

if (index > this.n) {

index = this.n;

}

//如果数组满

if (this.n == this.data.length) {

//temp copy

Object[] temp = this.data;

//new Container

this.data = new Object[temp.length*2];

//trans data

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

this.data[i] = temp[i];

}

}

//数据后移，index-last

for (int j = this.data.length-1; j >= index ; --j) {

this.data[j+1] = this.data[j];

}

//插入

this.data[index] = content;

this.n++;

return true;

}

//依据index删除元素

@Override

public T remove(int index) {

if (this.n !=0 && index >= 0 && index < this.n){

T oldElement = (T) this.data[index];

for (int i = index + 1; i < this.n ; i++) {

this.data[i] = this.data[i+1];

}

//设置尾巴

this.data[this.n - 1] = null;

this.n --;

return oldElement;

}

return null;

}

@Override

public boolean remove(T content) {

return false;

}

@Override

public boolean removeAll(T content) {

boolean result = false;

if (this.n !=0 && content != null){

int i = 0;

while (i < this.n){

if (content.equals(this.data[i])){

this.remove(i);

result = true;

}

i++;

}

}

return result;

}

@Override

public boolean add(T content) {

return false;

}

@Override

public void clear() {

}

@Override

public boolean contains(T content) {

return false;

}

@Override

public int indexOf(T content) {

if (content != null) {

for (int i = 0; i < this.n; i++) {

if (this.data[i].equals(content))

return i;

}

}

return -1;

}

}