public class TestLinkedList {
@Test
public void testQuery() {
LinkedList1<Integer> list=new LinkedList1<Integer>();
list.add(22);
list.add(66);
list.addFirst(77);
list.addLast(99);
Iterator i = list.iterator();//就有了所有的元素了。
while(i.hasNext()) {
System.out.println(i.next());
}
A a = new A(1, "1");// linklist.A@4de4b452
A b = new A(2, "2");// linklist.A@50b5ac82
LinkedList1<A> list1 = new LinkedList1<A>(Arrays.asList(a, b));// [linklist.A@4de4b452, linklist.A@50b5ac82]
LinkedList1 list2 = (LinkedList1) list1.clone();// [linklist.A@4de4b452, linklist.A@50b5ac82]。
// first，last等属性地址不一样了。里面的元素传递的还是地址。
System.out.println(list1);// [linklist.A@4de4b452, linklist.A@50b5ac82]
System.out.println(list2);// [linklist.A@4de4b452, linklist.A@50b5ac82]
a.k = 4;
a.s = "ff";
System.out.println(list1);// [linklist.A@4de4b452, linklist.A@50b5ac82],里面的a改变了。
System.out.println(list2);// [linklist.A@4de4b452, linklist.A@50b5ac82],里面的a改变了。
Object[] ss = list1.toArray();// [linklist.A@4de4b452, linklist.A@50b5ac82]
System.out.println(ss);
a.k = 8;
a.s = "刚刚";
System.out.println(ss);// ss里面的a也改变了。
Object[] ss1 = list1.toArray(new A[] {new A(3,"3"),new A(33,"33"),new A(444,"444"),new A(555,"555")});
//list的元素 + null + a数组后面的元素，
A c = new A(9,"d");
A d = new A(0,"pp");
A f = new A(89,"89");
A g = new A(90,"90");
list1.add(c);
list1.add(d);
list1.add(f);
list1.add(null);
list1.add(g);
LLSpliterator ll = (LLSpliterator) list1.spliterator();
Spliterator kk = ll.trySplit();
((Spliterator) ll).forEachRemaining(new Consumer<A>() {
public void accept(A a) {
System.out.println(a);
}
});
kk.forEachRemaining(new Consumer<A>() {
public void accept(A a) {
System.out.println(a);
}
});
}
}
class A {
public String s;
public int k;
A(int i, String b) {
this.s = b;
this.k = i;
}
}
public class LinkedList1<E> extends AbstractSequentialList1<E> implements List<E>, Deque<E>, Cloneable,
java.io.Serializable{
transient int size = 0;//结点个数
transient Node<E> first;
transient Node<E> last;
public LinkedList1() {
}
public LinkedList1(Collection<? extends E> c) {
this();
addAll(c);
}
private void linkFirst(E e) {//头部加一个元素
final Node<E> f = first;//first有可能是null
final Node<E> newNode = new Node<>(null, e, f);
first = newNode;
if (f == null)
last = newNode;
else
f.prev = newNode;
size++;
modCount++;
}
void linkLast(E e) {
final Node<E> l = last;//last有可能是null
final Node<E> newNode = new Node<>(l, e, null);
last = newNode;
if (l == null)
first = newNode;
else
l.next = newNode;
size++;
modCount++;
}
void linkBefore(E e, Node<E> succ) {
assert succ != null;
final Node<E> pred = succ.prev;//succ不为null，前驱有可能是null
final Node<E> newNode = new Node<>(pred, e, succ);
succ.prev = newNode;
if (pred == null)//succ是头结点
first = newNode;//新节点是头结点
else
pred.next = newNode;
size++;
modCount++;
}
//删除头结点
private E unlinkFirst(Node<E> f) {
assert f == first && f != null;
final E element = f.item;//要return出去的
final Node<E> next = f.next;//要修改前驱结点的
f.item = null;
f.next = null; // help GC
first = next;
if (next == null)
last = null;
else
next.prev = null;
size--;
modCount++;
return element;
}
//删除尾结点
private E unlinkLast(Node<E> l) {
assert l == last && l != null;
final E element = l.item;//要return出去的
final Node<E> prev = l.prev;//要修改后继结点的
l.item = null;
l.prev = null; // help GC
last = prev;
if (prev == null)
first = null;
else
prev.next = null;
size--;
modCount++;
return element;
}
//删除X结点
E unlink(Node<E> x) {
assert x != null;
final E element = x.item;
final Node<E> next = x.next;//next可能是null
final Node<E> prev = x.prev;//prev可能是null
if (prev == null) {
first = next;
} else {
prev.next = next;
x.prev = null;
}
if (next == null) {
last = prev;
} else {
next.prev = prev;
x.next = null;
}
x.item = null;
size--;
modCount++;
return element;
}
public E getFirst() {
final Node<E> f = first;
if (f == null)
throw new NoSuchElementException();
return f.item;
}
public E getLast() {
final Node<E> l = last;
if (l == null)
throw new NoSuchElementException();
return l.item;
}
public E removeFirst() {
final Node<E> f = first;
if (f == null)
throw new NoSuchElementException();
return unlinkFirst(f);
}
public E removeLast() {
final Node<E> l = last;
if (l == null)
throw new NoSuchElementException();
return unlinkLast(l);
}
public void addFirst(E e) {
linkFirst(e);
}
public void addLast(E e) {
linkLast(e);
}
public boolean contains(Object o) {
return indexOf(o) != -1;
}
public int size() {
return size;
}
public boolean add(E e) {
linkLast(e);
return true;
}
public boolean remove(Object o) {
if (o == null) {
for (Node<E> x = first; x != null; x = x.next) {
if (x.item == null) {
unlink(x);
return true;
}
}
} else {
for (Node<E> x = first; x != null; x = x.next) {
if (o.equals(x.item)) {
unlink(x);
return true;
}
}
}
return false;
}
//尾部添加，添加时候集合不能修改
public boolean addAll(Collection<? extends E> c) {
return addAll(size, c);
}
public boolean addAll(int index, Collection<? extends E> c) {
checkPositionIndex(index);
Object[] a = c.toArray();//集合转换为数组
int numNew = a.length;
if (numNew == 0)
return false;
Node<E> pred, succ;//pred和succ之间添加
if (index == size) {//尾部添加
succ = null;
pred = last;
} else {
succ = node(index);//中间结点succ后添加
pred = succ.prev;
}
//先把元素全部加到pred的后面
for (Object o : a) {
E e = (E) o;
Node<E> newNode = new Node<>(pred, e, null);
if (pred == null)
first = newNode;
else
pred.next = newNode;
pred = newNode;
}
//最后加上succ结点
if (succ == null) {
last = pred;
} else {
pred.next = succ;
succ.prev = pred;
}
size += numNew;
modCount++;
return true;
}
public void clear() {
for (Node<E> x = first; x != null; ) {
Node<E> next = x.next;
x.item = null;
x.next = null;
x.prev = null;//每个结点的3个属性全部清空
x = next;
}
first = last = null;
size = 0;
modCount++;
}
public E get(int index) {
checkElementIndex(index);
return node(index).item;
}
public E set(int index, E element) {
checkElementIndex(index);
Node<E> x = node(index);
E oldVal = x.item;
x.item = element;
return oldVal;
}
public void add(int index, E element) {
checkPositionIndex(index);
if (index == size)
linkLast(element);
else
linkBefore(element, node(index));
}
public E remove(int index) {
checkElementIndex(index);
return unlink(node(index));
}
private boolean isElementIndex(int index) {
return index >= 0 && index < size;
}
private boolean isPositionIndex(int index) {
return index >= 0 && index <= size;
}
private String outOfBoundsMsg(int index) {
return "Index: "+index+", Size: "+size;
}
private void checkElementIndex(int index) {
if (!isElementIndex(index))
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
private void checkPositionIndex(int index) {
if (!isPositionIndex(index))
throw new IndexOutOfBoundsException(outOfBoundsMsg(index));
}
//双向链表：只能从前找或者从后找。二分。下标为index，第index+1位置的元素。
Node<E> node(int index) {
assert isElementIndex(index);
if (index < (size >> 1)) {
Node<E> x = first;
for (int i = 0; i < index; i++)
x = x.next;
return x;
} else {
Node<E> x = last;
for (int i = size - 1; i > index; i--)
x = x.prev;
return x;
}
}
// Search Operations
public int indexOf(Object o) {//从前向后找，第一个遇到的。
int index = 0;
if (o == null) {
for (Node<E> x = first; x != null; x = x.next) {
if (x.item == null)
return index;
index++;
}
} else {
for (Node<E> x = first; x != null; x = x.next) {
if (o.equals(x.item))
return index;
index++;
}
}
return -1;
}
//从后面开始查找
public int lastIndexOf(Object o) {
int index = size;
if (o == null) {
for (Node<E> x = last; x != null; x = x.prev) {
index--;
if (x.item == null)
return index;
}
} else {
for (Node<E> x = last; x != null; x = x.prev) {
index--;
if (o.equals(x.item))
return index;
}
}
return -1;
}
//返回头结点元素，但不清空
public E peek() {
final Node<E> f = first;
return (f == null) ? null : f.item;
}
public E element() {
return getFirst();
}
//返回并清除头结点
public E poll() {
final Node<E> f = first;
return (f == null) ? null : unlinkFirst(f);
}
public E remove() {
return removeFirst();
}
//尾部添加
public boolean offer(E e) {
return add(e);
}
public boolean offerFirst(E e) {
addFirst(e);
return true;
}
public boolean offerLast(E e) {
addLast(e);
return true;
}
public E peekFirst() {
final Node<E> f = first;
return (f == null) ? null : f.item;
}
public E peekLast() {
final Node<E> l = last;
return (l == null) ? null : l.item;
}
public E pollFirst() {
final Node<E> f = first;
return (f == null) ? null : unlinkFirst(f);
}
public E pollLast() {
final Node<E> l = last;
return (l == null) ? null : unlinkLast(l);
}
public void push(E e) {
addFirst(e);
}
public E pop() {
return removeFirst();
}
public boolean removeFirstOccurrence(Object o) {//从前往后找
return remove(o);
}
public boolean removeLastOccurrence(Object o) {//从后往前找
if (o == null) {
for (Node<E> x = last; x != null; x = x.prev) {
if (x.item == null) {
unlink(x);
return true;
}
}
} else {
for (Node<E> x = last; x != null; x = x.prev) {
if (o.equals(x.item)) {
unlink(x);
return true;
}
}
}
return false;
}
public ListIterator<E> listIterator(int index) {
checkPositionIndex(index);
return new ListItr(index);//从index开始遍历,new之后就有了所有的元素了。
}
private class ListItr implements ListIterator<E> {
private Node<E> next;//还没有访问的元素，
private int nextIndex;//还没有访问的索引，
private Node<E> lastReturned;//遍历时候的元素
private int expectedModCount = modCount;
ListItr(int index) {
assert isPositionIndex(index);
next = (index == size) ? null : node(index);//下一个访问的元素
nextIndex = index;//下一个访问的索引
}
public boolean hasNext() {
return nextIndex < size;
}
public E next() {//遍历一次
checkForComodification();
if (!hasNext())
throw new NoSuchElementException();
lastReturned = next;
next = next.next;//修改next
nextIndex++;//修改下一个索引
return lastReturned.item;//返回元素
}
public boolean hasPrevious() {
return nextIndex > 0;//就可以减一
}
public E previous() {//前面一个
checkForComodification();
if (!hasPrevious())
throw new NoSuchElementException();
//next == null表示刚刚访问的元素是last元素，
lastReturned = next = (next == null) ? last : next.prev;
nextIndex--;
return lastReturned.item;
}
public int nextIndex() {
return nextIndex;
}
public int previousIndex() {
return nextIndex - 1;
}
public void remove() {
checkForComodification();
if (lastReturned == null)
throw new IllegalStateException();
Node<E> lastNext = lastReturned.next;
unlink(lastReturned);
if (next == lastReturned)
next = lastNext;
else
nextIndex--;
lastReturned = null;
expectedModCount++;
}
public void set(E e) {
if (lastReturned == null)
throw new IllegalStateException();
checkForComodification();
lastReturned.item = e;
}
public void add(E e) {
checkForComodification();
lastReturned = null;
if (next == null)
linkLast(e);
else
linkBefore(e, next);
nextIndex++;
expectedModCount++;
}
public void forEachRemaining(Consumer<? super E> action) {
Objects.requireNonNull(action);
//父List被修改了，就快速失败。
while (modCount == expectedModCount && nextIndex < size) {
action.accept(next.item);
lastReturned = next;
next = next.next;
nextIndex++;
}
checkForComodification();
}
final void checkForComodification() {
if (modCount != expectedModCount)//父List被修改了，就快速失败。
throw new ConcurrentModificationException();
}
}
private static class Node<E> {
E item;
Node<E> next;
Node<E> prev;
Node(Node<E> prev, E element, Node<E> next) {
this.item = element;
this.next = next;
this.prev = prev;
}
}
public Iterator<E> descendingIterator() {
return new DescendingIterator();
}
//从后往前遍历器
private class DescendingIterator implements Iterator<E> {
private final ListItr itr = new ListItr(size());
public boolean hasNext() {
return itr.hasPrevious();
}
public E next() {
return itr.previous();
}
public void remove() {
itr.remove();
}
}
private LinkedList1<E> superClone() {
try {
return (LinkedList1<E>) super.clone();//浅拷贝，地址复制拷贝。
} catch (CloneNotSupportedException e) {
throw new InternalError(e);
}
}
//深度拷贝重新建立一个。浅拷贝就是属性地址全是一样的，深拷贝是属性地址不一样。如果元素是对象，对象的地址还是一样。
public Object clone() {
LinkedList1<E> clone = superClone();//[linklist.A@4de4b452, linklist.A@50b5ac82]
System.out.println(this.first);//@24fcf36f
System.out.println(this.last);//@10feca44
System.out.println(clone.first);//@24fcf36f
System.out.println(clone.last);//@10feca44 。 浅拷贝属性地址是一样的。
clone.first = clone.last = null;
clone.size = 0;
clone.modCount = 0;
for (Node<E> x = first; x != null; x = x.next)
clone.add(x.item);//item也是地址
System.out.println(clone.first);//@3fb1549b
System.out.println(clone.last);//@ea6147e 。 深拷贝属性地址不是一样的。里面的元素还是地址传递，所以是一样的。
return clone;//[linklist.A@4de4b452, linklist.A@50b5ac82]
}
public Object[] toArray() {
Object[] result = new Object[size];
int i = 0;
for (Node<E> x = first; x != null; x = x.next)
result[i++] = x.item;//item传递的是地址，
return result;
}
public <T> T[] toArray(T[] a) {
if (a.length < size)//a的长度小，把a变成list的长度，并全部置为null。然后把list的元素赋值进去，返回的就是list的数组
a = (T[])java.lang.reflect.Array.newInstance(a.getClass().getComponentType(), size);
int i = 0;
Object[] result = a;
for (Node<E> x = first; x != null; x = x.next)
result[i++] = x.item;
if (a.length > size)//list的元素 + null + a数组后面的元素，
a[size] = null;
return a;
}
private static final long serialVersionUID = 876323262645176354L;
public void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
// Write out any hidden serialization magic
s.defaultWriteObject();
// Write out size
s.writeInt(size);
// Write out all elements in the proper order.
for (Node<E> x = first; x != null; x = x.next)
s.writeObject(x.item);
}
@SuppressWarnings("unchecked")
public void readObject(java.io.ObjectInputStream s)
throws java.io.IOException, ClassNotFoundException {
// Read in any hidden serialization magic
s.defaultReadObject();
// Read in size
int size = s.readInt();
// Read in all elements in the proper order.
for (int i = 0; i < size; i++)
linkLast((E)s.readObject());
}
@Override
public Spliterator<E> spliterator() {
return new LLSpliterator<E>(this, -1, 0);
}
/** A customized variant of Spliterators.IteratorSpliterator */
static final class LLSpliterator<E> implements Spliterator<E> {
static final int BATCH_UNIT = 1 << 10; // 批处理数组大小增量, 1024
static final int MAX_BATCH = 1 << 25; // 最大批处理数组大小, 33554432
final LinkedList1<E> list;
Node<E> current; // 当前遍历节点
int est; //尾节点，初始值为-1，
int expectedModCount; // initialized when est set
int batch; // 拆分的批量大小
LLSpliterator(LinkedList1<E> list, int est, int expectedModCount) {
this.list = list;
this.est = est;//尾节点，初始值为-1，
this.expectedModCount = expectedModCount;
}
final int getEst() {
int s; // force initialization
final LinkedList1<E> lst;
if ((s = est) < 0) {//est为-1
if ((lst = list) == null)
s = est = 0;
else {
expectedModCount = lst.modCount;
current = lst.first;
s = est = lst.size;
}
}
return s;
}
public long estimateSize() { return (long) getEst(); }
public Spliterator<E> trySplit() {
Node<E> p;
int s = getEst();//7
if (s > 1 && (p = current) != null) {
int n = batch + BATCH_UNIT;//1024+batch
if (n > s)
n = s;
if (n > MAX_BATCH)//33554432，最大大小，
n = MAX_BATCH;//n是s,1024+batch,33554432中最小的。
Object[] a = new Object[n];
int j = 0;
do {
a[j++] = p.item;
} while ((p = p.next) != null && j < n);//到达list结尾 或者 把s填满，
current = p;//null
batch = j;//7
est = s - j;//0
return Spliterators.spliterator(a, 0, j, Spliterator.ORDERED);//返回ArraySpliterator
}
return null;
}
public void forEachRemaining(Consumer<? super E> action) {
Node<E> p; int n;
if (action == null) throw new NullPointerException();
if ((n = getEst()) > 0 && (p = current) != null) {
current = null;
est = 0;
do {
E e = p.item;
p = p.next;
action.accept(e);
} while (p != null && --n > 0);
}
if (list.modCount != expectedModCount)
throw new ConcurrentModificationException();
}
public boolean tryAdvance(Consumer<? super E> action) {
Node<E> p;
if (action == null) throw new NullPointerException();
if (getEst() > 0 && (p = current) != null) {
--est;
E e = p.item;
current = p.next;
action.accept(e);
if (list.modCount != expectedModCount)
throw new ConcurrentModificationException();
return true;
}
return false;
}
public int characteristics() {
return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
}
}
}
public abstract class AbstractSequentialList1<E> extends AbstractList<E> {
protected AbstractSequentialList1() {
}
public E get(int index) {
try {
return listIterator(index).next();
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException("Index: "+index);
}
}
public E set(int index, E element) {
try {
ListIterator<E> e = listIterator(index);
E oldVal = e.next();
e.set(element);
return oldVal;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException("Index: "+index);
}
}
public void add(int index, E element) {
try {
listIterator(index).add(element);
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException("Index: "+index);
}
}
public E remove(int index) {
try {
ListIterator<E> e = listIterator(index);
E outCast = e.next();
e.remove();
return outCast;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException("Index: "+index);
}
}
// Bulk Operations
public boolean addAll(int index, Collection<? extends E> c) {
try {
boolean modified = false;
ListIterator<E> e1 = listIterator(index);
Iterator<? extends E> e2 = c.iterator();
while (e2.hasNext()) {
e1.add(e2.next());
modified = true;
}
return modified;
} catch (NoSuchElementException exc) {
throw new IndexOutOfBoundsException("Index: "+index);
}
}
// Iterators
public Iterator<E> iterator() {
return listIterator();
}
public abstract ListIterator<E> listIterator(int index);
}
浙公网安备 33010602011771号