clear()删除错有缓冲区里的数据
public void clear() { modCount++; final Object[] es = elementData; for (int to = size, i = size = 0; i < to; i++)//实际存储数据置0，从0到实际存储的位置循环置null es[i] = null; }addAll(Collection<? extends E> c)添加集合到当前集合
public boolean addAll(Collection<? extends E> c) { Object[] a = c.toArray();//转化为数组 modCount++; int numNew = a.length;//添加数据长度 if (numNew == 0) return false;//长度为0直接返回false Object[] elementData; final int s; if (numNew > (elementData = this.elementData).length - (s = size))//旧数据长度+新数据长度大于缓冲区大小，就扩容 elementData = grow(s + numNew);//扩大为可以容纳旧数据+新数据大小 System.arraycopy(a, 0, elementData, s, numNew);//新数据从0位开始复制到缓冲区的s位处，复制长度为新数据长度 size = s + numNew; return true; }addAll(int index, Collection<? extends E> c)添加集合到当前集合的固定位置
public boolean addAll(int index, Collection<? extends E> c) { rangeCheckForAdd(index);//确认下标 Object[] a = c.toArray();//转数组 modCount++; int numNew = a.length; if (numNew == 0) return false;//长度为0直接返回 Object[] elementData; final int s; if (numNew > (elementData = this.elementData).length - (s = size))//旧数据长度+新数据长度大于缓冲区大小，就扩容 elementData = grow(s + numNew); int numMoved = s - index;//存储长度减去index得出就是要移动数据的长度 if (numMoved > 0) System.arraycopy(elementData, index,elementData, index + numNew,numMoved);//把缓冲区从index移动到index + numNew，移动长度为numMoved System.arraycopy(a, 0, elementData, index, numNew);//把集合从0位移动到缓冲区index位，共移动集合的长度个数据 size = s + numNew;//实际存储数更改为size+集合长度 return true;//返回true }removeRange(int fromIndex, int toIndex)删除介于(包含)fromIndex和toIndex（不包含）的所有元素
protected void removeRange(int fromIndex, int toIndex) { if (fromIndex > toIndex) { throw new IndexOutOfBoundsException( outOfBoundsMsg(fromIndex, toIndex)); } modCount++; shiftTailOverGap(elementData, fromIndex, toIndex); }shiftTailOverGap(Object[] es, int lo, int hi)删除lo(包含)到hi（不包含）期间的元素
private void shiftTailOverGap(Object[] es, int lo, int hi) { System.arraycopy(es, hi, es, lo, size - hi);//从hi位以后的数据复制到lo位，共复制size-hi个数据 for (int to = size, i = (size -= hi - lo); i < to; i++) es[i] = null;//置0 }rangeCheckForAdd(int index)判断是否在区间内
private void rangeCheckForAdd(int index) { if (index > size || index < 0) throw new IndexOutOfBoundsException(outOfBoundsMsg(index)); }下标越界消息
private String outOfBoundsMsg(int index) { return "Index: "+index+", Size: "+size; } private static String outOfBoundsMsg(int fromIndex, int toIndex) { return "From Index: " + fromIndex + " > To Index: " + toIndex; }removeAll(Collection<?> c) 删除缓冲区中，集合包含的数据
public boolean removeAll(Collection<?> c) { return batchRemove(c, false, 0, size); }retainAll(Collection<?> c)保留缓冲区中，集合包含的数据
public boolean retainAll(Collection<?> c) { return batchRemove(c, true, 0, size); }batchRemove(Collection<?> c, boolean complement,final int from, final int end)false是删除传入集合包含元素，true是保留传入集合包含元素
boolean batchRemove(Collection<?> c, boolean complement, final int from, final int end) { Objects.requireNonNull(c); final Object[] es = elementData; int r; // Optimize for initial run of survivors for (r = from;; r++) { if (r == end)//操作长度为0直接返回false return false; if (c.contains(es[r]) != complement)//为true的时候，查找到第一个不保留位r。为false时候查找到第一个要删除的位 break; } int w = r++; try { for (Object e; r < end; r++) if (c.contains(e = es[r]) == complement)//为true时把在集合的元素往前移，为false时，不在集合的元素往前移动 es[w++] = e; } catch (Throwable ex) { // Preserve behavioral compatibility with AbstractCollection, // even if c.contains() throws. System.arraycopy(es, r, es, w, end - r); w += end - r; throw ex; } finally { modCount += end - w; shiftTailOverGap(es, w, end);//删除尾部元素 } return true; }writeObject(java.io.ObjectOutputStream s)输出对象
private void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException { // Write out element count, and any hidden stuff int expectedModCount = modCount; s.defaultWriteObject(); // Write out size as capacity for behavioral compatibility with clone() s.writeInt(size); // Write out all elements in the proper order. for (int i=0; i<size; i++) { s.writeObject(elementData[i]);//循环输出对象 } if (modCount != expectedModCount) { throw new ConcurrentModificationException();//线程安全 } }readObject(java.io.ObjectInputStream s)读取对象
private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException { // Read in size, and any hidden stuff s.defaultReadObject(); // Read in capacity s.readInt(); // ignored if (size > 0) {//数据量大于0 // like clone(), allocate array based upon size not capacity SharedSecrets.getJavaObjectInputStreamAccess().checkArray(s, Object[].class, size); Object[] elements = new Object[size]; // Read in all elements in the proper order. for (int i = 0; i < size; i++) { elements[i] = s.readObject(); } elementData = elements; } else if (size == 0) {//数据量等于0 elementData = EMPTY_ELEMENTDATA; } else { throw new java.io.InvalidObjectException("Invalid size: " + size); } }listIterator()返回迭代器
public ListIterator<E> listIterator() { return new ListItr(0); }listIterator(int index)返回迭代器
public ListIterator<E> listIterator(int index) { rangeCheckForAdd(index);// return new ListItr(index); }