哪位高手帮分析一下如下代码，研究了半天没搞明白，感谢

[hiqrf]

public void add(int location, E object) {
int size = lastIndex - firstIndex;
if (0 < location && location < size) {
if (firstIndex == 0 && lastIndex == array.length) {
growForInsert(location, 1);
} else if ((location < size / 2 && firstIndex > 0)
|| lastIndex == array.length) {
System.arraycopy(array, firstIndex, array, --firstIndex,
location);
} else {
int index = location + firstIndex;
System.arraycopy(array, index, array, index + 1, size
- location);
lastIndex++;
}
array[location + firstIndex] = object;
} else if (location == 0) {
if (firstIndex == 0) {
growAtFront(1);
}
array[--firstIndex] = object;
} else if (location == size) {
if (lastIndex == array.length) {
growAtEnd(1);
}
array[lastIndex++] = object;
} else {
throw new IndexOutOfBoundsException(Messages.getString("luni.0A",
location, lastIndex - firstIndex));
}

modCount++;
}

[litiebiao2012]

能不能使用java代码格式输出呢?