ArrayList的SubList关注点

subList是arrayList的内部类

private class SubList extends AbstractList<E> implements RandomAccess {
    private final AbstractList<E> parent;
    private final int parentOffset;
    private final int offset;
    int size;

    SubList(AbstractList<E> parent,
            int offset, int fromIndex, int toIndex) {
        this.parent = parent;
        this.parentOffset = fromIndex;
        this.offset = offset + fromIndex;
        this.size = toIndex - fromIndex;
        this.modCount = ArrayList.this.modCount;
    }

1.非结构性修改父/子，都会影响彼此

2.子结构性修改，会反映到父类

3.对父结构结构性修改，会报错

 

SubList