public static int sizeOfArrayIntList(int len) 
{
        return sizeOfObject(PTR + INT) + sizeOfIntArray(len);
}

 public static int sizeOfArrayList(int len) 
{
        return sizeOfObject(PTR + 2*INT) + sizeOfObjectArray(len);
}

 public static int sizeOfCharArray(int len) 
{
        return sizeOfObject(INT + CHAR*len);
}

 public static int sizeOfHashMap(int len) 
{
        return sizeOfObject(4*PTR + 4*INT) + sizeOfObjectArray(len) 
            + len * sizeOfObject(3*PTR + INT); // entries
}

 public static int sizeOfIntArray(int len) 
{
        return sizeOfObject(INT + INT*len);
}

 public static int sizeOfObject(int n) 
{
        return sizeOf(OBJECT_HEADER + n);
}

 public static int sizeOfObjectArray(int len) 
{
        return sizeOfObject(INT + PTR*len);
}

 public static int sizeOfString(int len) 
{
        return sizeOfObject(3*INT + PTR) + sizeOfCharArray(len);
}