lonely-tiger/ArrayList.h

#ifndef ARRAYLIST_H
#define ARRAYLIST_H

#include <cstring>

template<class T>
class ArrayList
{
public:
    ArrayList()
    {
        pos = 0;
        capacity = 4;
        data = new T[capacity];
    }
    
    ArrayList(const ArrayList& orig)
    {
        pos = orig.pos;
        capacity = orig.capacity;
        data = new T[capacity];
        memcpy(data, orig.data, capacity * sizeof(T));
    }
    
    ArrayList& operator=(const ArrayList& orig)
    {
        delete[] data;
        
        pos = orig.pos;
        capacity = orig.capacity;
        data = new T[capacity];
        memcpy(data, orig.data, capacity * sizeof(T));
        
        return *this;
    }
    
    virtual ~ArrayList()
    {
        delete[] data;
    }
    
    int getSize()
    {
        return pos;
    }
    
    void clear()
    {
        memset(data, 0, sizeof(T) * pos);
        pos = 0;
    }
    
    void add(T t)
    {
        if(pos >= capacity)
        {
            int newCapacity = capacity * 2;
            T* t = new T[newCapacity];
            memcpy(t, data, capacity * sizeof(T));
            delete[] data;
            data = t;
            capacity = newCapacity;
        }
        data[pos] = t;
        pos++;
    }
    
    void remove(int index)
    {
        if(index < 0 || index >= pos)
        {
            return;
        }
        for(int i = index; i < pos - 1; i++)
        {
            data[i] = data[i + 1];
        }
        memset(data + pos - 1, 0, sizeof(T));
        pos--;
    }
    
    void forEach(void (*f) (T))
    {
        for(int i = 0; i < pos; i++)
        {
            f(data[i]);
        }
    }
private:
    int capacity;
    int pos;
    T* data;
};

#endif