全面的基础微网站开发,wordpress 页面 置顶,牡丹江,wordpress根目录在前些天发现了一个巨牛的人工智能学习网站#xff0c;通俗易懂#xff0c;风趣幽默#xff0c;忍不住分享一下给大家。点击跳转到教程。 1.继承关系#xff1a;public class ArrayListE extends AbstractListEimplements ListE, RandomAccess, Clon… 前些天发现了一个巨牛的人工智能学习网站通俗易懂风趣幽默忍不住分享一下给大家。点击跳转到教程。 1.继承关系public class ArrayListE extends AbstractListEimplements ListE, RandomAccess, Cloneable, java.io.Serializable2. 属性// 默认容量private static final int DEFAULT_CAPACITY 10;// 空数组第一次存入元素时更新大小为 DEFAULT_CAPACITYprivate static final Object[] EMPTY_ELEMENTDATA {};// 空数组默认设定大小为 DEFAULT_CAPACITYprivate static final Object[] DEFAULTCAPACITY_EMPTY_ELEMENTDATA {};// 添加第一个元素时扩展到默认容量transient关闭序列化transient Object[] elementData;// 数组中元素个数private int size;3.方法// 构造函数initialCapacity 集合容量该值为0时设定集合为 EMPTY_ELEMENTDATA否则取其正值。public ArrayList(int initialCapacity) {if (initialCapacity 0) {this.elementData new Object[initialCapacity];} else if (initialCapacity 0) {this.elementData EMPTY_ELEMENTDATA;} else {throw new IllegalArgumentException(Illegal Capacity: initialCapacity);}}// 无参构造默认设定大小为 DEFAULT_CAPACITYpublic ArrayList() {this.elementData DEFAULTCAPACITY_EMPTY_ELEMENTDATA;}// 构造函数拷贝已知集合若参数为空集合则使用 EMPTY_ELEMENTDATA。public ArrayList(Collection? extends E c) {elementData c.toArray();if ((size elementData.length) ! 0) {// c.toArray might (incorrectly) not return Object[] (see 6260652)if (elementData.getClass() ! Object[].class)elementData Arrays.copyOf(elementData, size, Object[].class);} else {// replace with empty array.this.elementData EMPTY_ELEMENTDATA;}}// 将容量调整为数组的当前大小可以最小化存储空间。public void trimToSize() {modCount;if (size elementData.length) {elementData (size 0)? EMPTY_ELEMENTDATA: Arrays.copyOf(elementData, size);}}// 增加此实例的容量minCapacity 所需的最小容量public void ensureCapacity(int minCapacity) {int minExpand (elementData ! DEFAULTCAPACITY_EMPTY_ELEMENTDATA)// any size if not default element table? 0// larger than default for default empty table. Its already// supposed to be at default size.: DEFAULT_CAPACITY;if (minCapacity minExpand) {ensureExplicitCapacity(minCapacity);}}private void ensureCapacityInternal(int minCapacity) {if (elementData DEFAULTCAPACITY_EMPTY_ELEMENTDATA) {minCapacity Math.max(DEFAULT_CAPACITY, minCapacity);}ensureExplicitCapacity(minCapacity);}private void ensureExplicitCapacity(int minCapacity) {modCount;// overflow-conscious codeif (minCapacity - elementData.length 0)grow(minCapacity);}// 数组最大容量分配过大容量可能会导致 OOM 异常因为超过了虚拟机限制private static final int MAX_ARRAY_SIZE Integer.MAX_VALUE - 8;// 增加容量到可以容纳 minCapacity 个元素。private void grow(int minCapacity) {// overflow-conscious codeint oldCapacity elementData.length;int newCapacity oldCapacity (oldCapacity 1);if (newCapacity - minCapacity 0)newCapacity minCapacity;if (newCapacity - MAX_ARRAY_SIZE 0)newCapacity hugeCapacity(minCapacity);// minCapacity is usually close to size, so this is a win:elementData Arrays.copyOf(elementData, newCapacity);}private static int hugeCapacity(int minCapacity) {if (minCapacity 0) // overflowthrow new OutOfMemoryError();return (minCapacity MAX_ARRAY_SIZE) ?Integer.MAX_VALUE :MAX_ARRAY_SIZE;}// 返回集合元素个数public int size() {return size;}// 检查是否为空public boolean isEmpty() {return size 0;}// 检查是否存在元素 o public boolean contains(Object o) {return indexOf(o) 0;}// 返回指定元素第一次出现的索引无则返回 -1 。public int indexOf(Object o) {if (o null) {for (int i 0; i size; i)if (elementData[i]null)return i;} else {for (int i 0; i size; i)if (o.equals(elementData[i]))return i;}return -1;}// 返回指定元素最后一次出现的索引无则返回 -1 。public int lastIndexOf(Object o) {if (o null) {for (int i size-1; i 0; i--)if (elementData[i]null)return i;} else {for (int i size-1; i 0; i--)if (o.equals(elementData[i]))return i;}return -1;}// 浅clone不会复制元素本身。public Object clone() {try {ArrayList? v (ArrayList?) super.clone();v.elementData Arrays.copyOf(elementData, size);v.modCount 0;return v;} catch (CloneNotSupportedException e) {// this shouldnt happen, since we are Cloneablethrow new InternalError(e);}}// 返回包含所有元素的数组该数组是安全的。此方法分配的是一个全新的数组没有对它的引用存在故调用者可对其自由修改。public Object[] toArray() {return Arrays.copyOf(elementData, size);}// 返回包含参数数组中所有元素的数组。SuppressWarnings(unchecked)public T T[] toArray(T[] a) {if (a.length size)// 建一个 a 类型的新数组, 并填充当前集合的元素到其中。return (T[]) Arrays.copyOf(elementData, size, a.getClass());System.arraycopy(elementData, 0, a, 0, size);if (a.length size)a[size] null;return a;}// 返回对应索引位的元素 SuppressWarnings(unchecked)E elementData(int index) {return (E) elementData[index];}// 返回对应索引位的元素提供对外访问调用上一方法。 public E get(int index) {rangeCheck(index);return elementData(index);}// 替换对应索引位的元素public E set(int index, E element) {rangeCheck(index);E oldValue elementData(index);elementData[index] element;return oldValue;}// 于末尾新增指定元素public boolean add(E e) {ensureCapacityInternal(size 1); // Increments modCount!!elementData[size] e;return true;}// 指定索引位插入式新增public void add(int index, E element) {rangeCheckForAdd(index);ensureCapacityInternal(size 1); // Increments modCount!!System.arraycopy(elementData, index, elementData, index 1,size - index);elementData[index] element;size;}// 移除对应索引位元素public E remove(int index) {rangeCheck(index);modCount;E oldValue elementData(index);int numMoved size - index - 1;if (numMoved 0)System.arraycopy(elementData, index1, elementData, index,numMoved);elementData[--size] null; // clear to let GC do its workreturn oldValue;}// 删除第一个匹配指定元素的元素若不存在匹配元素则不变。public boolean remove(Object o) {if (o null) {for (int index 0; index size; index)if (elementData[index] null) {fastRemove(index);return true;}} else {for (int index 0; index size; index)if (o.equals(elementData[index])) {fastRemove(index);return true;}}return false;}// 快速删除跳过边界检查且无返回private void fastRemove(int index) {modCount;int numMoved size - index - 1;if (numMoved 0)System.arraycopy(elementData, index1, elementData, index,numMoved);elementData[--size] null; // clear to let GC do its work}// 清空集合public void clear() {modCount;// clear to let GC do its workfor (int i 0; i size; i)elementData[i] null;size 0;}// 追加指定非空集合所有元素到本集合末尾public boolean addAll(Collection? extends E c) {Object[] a c.toArray();int numNew a.length;ensureCapacityInternal(size numNew); // Increments modCountSystem.arraycopy(a, 0, elementData, size, numNew);size numNew;return numNew ! 0;}// 从指定位置开始插入指定非空集合中的所有元素public boolean addAll(int index, Collection? extends E c) {rangeCheckForAdd(index);Object[] a c.toArray();int numNew a.length;ensureCapacityInternal(size numNew); // Increments modCountint numMoved size - index;if (numMoved 0)System.arraycopy(elementData, index, elementData, index numNew,numMoved);System.arraycopy(a, 0, elementData, index, numNew);size numNew;return numNew ! 0;}// 删除介于指定索引位之间的元素protected void removeRange(int fromIndex, int toIndex) {modCount;int numMoved size - toIndex;System.arraycopy(elementData, toIndex, elementData, fromIndex,numMoved);// clear to let GC do its workint newSize size - (toIndex-fromIndex);for (int i newSize; i size; i) {elementData[i] null;}size newSize;}// 检查指定索引位是否大于集合总容量此方法在访问数组元素前使用。private void rangeCheck(int index) {if (index size)throw new IndexOutOfBoundsException(outOfBoundsMsg(index));}// add 和 addAll使用的 rangeCheck 版本private void rangeCheckForAdd(int index) {if (index size || index 0)throw new IndexOutOfBoundsException(outOfBoundsMsg(index));}// 构造索引越界下标越界的返回信息内容索引值 集合总容量大小。private String outOfBoundsMsg(int index) {return Index: index, Size: size;}// 删除指定集合中的所有元素public boolean removeAll(Collection? c) {Objects.requireNonNull(c);return batchRemove(c, false);}// 仅保留指定集合中的元素删除其余元素。public boolean retainAll(Collection? c) {Objects.requireNonNull(c);return batchRemove(c, true);}private boolean batchRemove(Collection? c, boolean complement) {final Object[] elementData this.elementData;int r 0, w 0;boolean modified false;try {for (; r size; r)if (c.contains(elementData[r]) complement)elementData[w] elementData[r];} finally {// Preserve behavioral compatibility with AbstractCollection,// even if c.contains() throws.if (r ! size) {System.arraycopy(elementData, r,elementData, w,size - r);w size - r;}if (w ! size) {// clear to let GC do its workfor (int i w; i size; i)elementData[i] null;modCount size - w;size w;modified true;}}return modified;}// 保存到流即序列化。private void writeObject(java.io.ObjectOutputStream s)throws java.io.IOException{// Write out element count, and any hidden stuffint expectedModCount modCount;s.defaultWriteObject();// Write out size as capacity for behavioural compatibility with clone()s.writeInt(size);// Write out all elements in the proper order.for (int i0; isize; i) {s.writeObject(elementData[i]);}if (modCount ! expectedModCount) {throw new ConcurrentModificationException();}}// 从流重组为集合即反序列化。private void readObject(java.io.ObjectInputStream s)throws java.io.IOException, ClassNotFoundException {elementData EMPTY_ELEMENTDATA;// Read in size, and any hidden stuffs.defaultReadObject();// Read in capacitys.readInt(); // ignoredif (size 0) {// be like clone(), allocate array based upon size not capacityensureCapacityInternal(size);Object[] a elementData;// Read in all elements in the proper order.for (int i0; isize; i) {a[i] s.readObject();}}}// 返回从指定索引位开始的迭代器public ListIteratorE listIterator(int index) {if (index 0 || index size)throw new IndexOutOfBoundsException(Index: index);return new ListItr(index);}// 以适当的顺序返回包含此集合所有元素的集合迭代器。public ListIteratorE listIterator() {return new ListItr(0);}// 以适当的顺序返回包含此集合所有元素的迭代器。public IteratorE iterator() {return new Itr();}// AbstractList.Itr 的优化版本private class Itr implements IteratorE {int cursor; // index of next element to returnint lastRet -1; // index of last element returned; -1 if no suchint expectedModCount modCount;public boolean hasNext() {return cursor ! size;}SuppressWarnings(unchecked)public E next() {checkForComodification();int i cursor;if (i size)throw new NoSuchElementException();Object[] elementData ArrayList.this.elementData;if (i elementData.length)throw new ConcurrentModificationException();cursor i 1;return (E) elementData[lastRet i];}public void remove() {if (lastRet 0)throw new IllegalStateException();checkForComodification();try {ArrayList.this.remove(lastRet);cursor lastRet;lastRet -1;expectedModCount modCount;} catch (IndexOutOfBoundsException ex) {throw new ConcurrentModificationException();}}OverrideSuppressWarnings(unchecked)public void forEachRemaining(Consumer? super E consumer) {Objects.requireNonNull(consumer);final int size ArrayList.this.size;int i cursor;if (i size) {return;}final Object[] elementData ArrayList.this.elementData;if (i elementData.length) {throw new ConcurrentModificationException();}while (i ! size modCount expectedModCount) {consumer.accept((E) elementData[i]);}// update once at end of iteration to reduce heap write trafficcursor i;lastRet i - 1;checkForComodification();}final void checkForComodification() {if (modCount ! expectedModCount)throw new ConcurrentModificationException();}}// AbstractList.ListItr 的优化版本private class ListItr extends Itr implements ListIteratorE {ListItr(int index) {super();cursor index;}public boolean hasPrevious() {return cursor ! 0;}public int nextIndex() {return cursor;}public int previousIndex() {return cursor - 1;}SuppressWarnings(unchecked)public E previous() {checkForComodification();int i cursor - 1;if (i 0)throw new NoSuchElementException();Object[] elementData ArrayList.this.elementData;if (i elementData.length)throw new ConcurrentModificationException();cursor i;return (E) elementData[lastRet i];}public void set(E e) {if (lastRet 0)throw new IllegalStateException();checkForComodification();try {ArrayList.this.set(lastRet, e);} catch (IndexOutOfBoundsException ex) {throw new ConcurrentModificationException();}}public void add(E e) {checkForComodification();try {int i cursor;ArrayList.this.add(i, e);cursor i 1;lastRet -1;expectedModCount modCount;} catch (IndexOutOfBoundsException ex) {throw new ConcurrentModificationException();}}}// 返回子集合前闭后开。fromIndex toIndex 时返回空集合。public ListE subList(int fromIndex, int toIndex) {subListRangeCheck(fromIndex, toIndex, size);return new SubList(this, 0, fromIndex, toIndex);}static void subListRangeCheck(int fromIndex, int toIndex, int size) {if (fromIndex 0)throw new IndexOutOfBoundsException(fromIndex fromIndex);if (toIndex size)throw new IndexOutOfBoundsException(toIndex toIndex);if (fromIndex toIndex)throw new IllegalArgumentException(fromIndex( fromIndex ) toIndex( toIndex ));}private class SubList extends AbstractListE implements RandomAccess {private final AbstractListE parent;private final int parentOffset;private final int offset;int size;SubList(AbstractListE 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;}public E set(int index, E e) {rangeCheck(index);checkForComodification();E oldValue ArrayList.this.elementData(offset index);ArrayList.this.elementData[offset index] e;return oldValue;}public E get(int index) {rangeCheck(index);checkForComodification();return ArrayList.this.elementData(offset index);}public int size() {checkForComodification();return this.size;}public void add(int index, E e) {rangeCheckForAdd(index);checkForComodification();parent.add(parentOffset index, e);this.modCount parent.modCount;this.size;}public E remove(int index) {rangeCheck(index);checkForComodification();E result parent.remove(parentOffset index);this.modCount parent.modCount;this.size--;return result;}protected void removeRange(int fromIndex, int toIndex) {checkForComodification();parent.removeRange(parentOffset fromIndex,parentOffset toIndex);this.modCount parent.modCount;this.size - toIndex - fromIndex;}public boolean addAll(Collection? extends E c) {return addAll(this.size, c);}public boolean addAll(int index, Collection? extends E c) {rangeCheckForAdd(index);int cSize c.size();if (cSize0)return false;checkForComodification();parent.addAll(parentOffset index, c);this.modCount parent.modCount;this.size cSize;return true;}public IteratorE iterator() {return listIterator();}public ListIteratorE listIterator(final int index) {checkForComodification();rangeCheckForAdd(index);final int offset this.offset;return new ListIteratorE() {int cursor index;int lastRet -1;int expectedModCount ArrayList.this.modCount;public boolean hasNext() {return cursor ! SubList.this.size;}SuppressWarnings(unchecked)public E next() {checkForComodification();int i cursor;if (i SubList.this.size)throw new NoSuchElementException();Object[] elementData ArrayList.this.elementData;if (offset i elementData.length)throw new ConcurrentModificationException();cursor i 1;return (E) elementData[offset (lastRet i)];}public boolean hasPrevious() {return cursor ! 0;}SuppressWarnings(unchecked)public E previous() {checkForComodification();int i cursor - 1;if (i 0)throw new NoSuchElementException();Object[] elementData ArrayList.this.elementData;if (offset i elementData.length)throw new ConcurrentModificationException();cursor i;return (E) elementData[offset (lastRet i)];}SuppressWarnings(unchecked)public void forEachRemaining(Consumer? super E consumer) {Objects.requireNonNull(consumer);final int size SubList.this.size;int i cursor;if (i size) {return;}final Object[] elementData ArrayList.this.elementData;if (offset i elementData.length) {throw new ConcurrentModificationException();}while (i ! size modCount expectedModCount) {consumer.accept((E) elementData[offset (i)]);}// update once at end of iteration to reduce heap write trafficlastRet cursor i;checkForComodification();}public int nextIndex() {return cursor;}public int previousIndex() {return cursor - 1;}public void remove() {if (lastRet 0)throw new IllegalStateException();checkForComodification();try {SubList.this.remove(lastRet);cursor lastRet;lastRet -1;expectedModCount ArrayList.this.modCount;} catch (IndexOutOfBoundsException ex) {throw new ConcurrentModificationException();}}public void set(E e) {if (lastRet 0)throw new IllegalStateException();checkForComodification();try {ArrayList.this.set(offset lastRet, e);} catch (IndexOutOfBoundsException ex) {throw new ConcurrentModificationException();}}public void add(E e) {checkForComodification();try {int i cursor;SubList.this.add(i, e);cursor i 1;lastRet -1;expectedModCount ArrayList.this.modCount;} catch (IndexOutOfBoundsException ex) {throw new ConcurrentModificationException();}}final void checkForComodification() {if (expectedModCount ! ArrayList.this.modCount)throw new ConcurrentModificationException();}};}public ListE subList(int fromIndex, int toIndex) {subListRangeCheck(fromIndex, toIndex, size);return new SubList(this, offset, fromIndex, toIndex);}private void rangeCheck(int index) {if (index 0 || index this.size)throw new IndexOutOfBoundsException(outOfBoundsMsg(index));}private void rangeCheckForAdd(int index) {if (index 0 || index this.size)throw new IndexOutOfBoundsException(outOfBoundsMsg(index));}private String outOfBoundsMsg(int index) {return Index: index, Size: this.size;}private void checkForComodification() {if (ArrayList.this.modCount ! this.modCount)throw new ConcurrentModificationException();}public SpliteratorE spliterator() {checkForComodification();return new ArrayListSpliteratorE(ArrayList.this, offset,offset this.size, this.modCount);}}Overridepublic void forEach(Consumer? super E action) {Objects.requireNonNull(action);final int expectedModCount modCount;SuppressWarnings(unchecked)final E[] elementData (E[]) this.elementData;final int size this.size;for (int i0; modCount expectedModCount i size; i) {action.accept(elementData[i]);}if (modCount ! expectedModCount) {throw new ConcurrentModificationException();}}// 创建一个拆分器since 1.8。Overridepublic SpliteratorE spliterator() {return new ArrayListSpliterator(this, 0, -1, 0);}// 延迟初始化的拆分器。static final class ArrayListSpliteratorE implements SpliteratorE {// 如果集合结构是不变的没有CRUD操作则用 Arrays.spliterator 实现拆分. private final ArrayListE list;private int index; // current index, modified on advance/splitprivate int fence; // -1 until used; then one past last indexprivate int expectedModCount; // initialized when fence set/ Create new spliterator covering the given range /ArrayListSpliterator(ArrayListE list, int origin, int fence,int expectedModCount) {this.list list; // OK if null unless traversedthis.index origin;this.fence fence;this.expectedModCount expectedModCount;}private int getFence() { // initialize fence to size on first useint hi; // (a specialized variant appears in method forEach)ArrayListE lst;if ((hi fence) 0) {if ((lst list) null)hi fence 0;else {expectedModCount lst.modCount;hi fence lst.size;}}return hi;}public ArrayListSpliteratorE trySplit() {int hi getFence(), lo index, mid (lo hi) 1;return (lo mid) ? null : // divide range in half unless too smallnew ArrayListSpliteratorE(list, lo, index mid,expectedModCount);}public boolean tryAdvance(Consumer? super E action) {if (action null)throw new NullPointerException();int hi getFence(), i index;if (i hi) {index i 1;SuppressWarnings(unchecked) E e (E)list.elementData[i];action.accept(e);if (list.modCount ! expectedModCount)throw new ConcurrentModificationException();return true;}return false;}public void forEachRemaining(Consumer? super E action) {int i, hi, mc; // hoist accesses and checks from loopArrayListE lst; Object[] a;if (action null)throw new NullPointerException();if ((lst list) ! null (a lst.elementData) ! null) {if ((hi fence) 0) {mc lst.modCount;hi lst.size;}elsemc expectedModCount;if ((i index) 0 (index hi) a.length) {for (; i hi; i) {SuppressWarnings(unchecked) E e (E) a[i];action.accept(e);}if (lst.modCount mc)return;}}throw new ConcurrentModificationException();}public long estimateSize() {return (long) (getFence() - index);}public int characteristics() {return Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;}}// Predicate 函数式编程参见个人博客 https://blog.csdn.net/jiangyu1013/article/details/103500724Overridepublic boolean removeIf(Predicate? super E filter) {Objects.requireNonNull(filter);// figure out which elements are to be removed// any exception thrown from the filter predicate at this stage// will leave the collection unmodifiedint removeCount 0;final BitSet removeSet new BitSet(size);final int expectedModCount modCount;final int size this.size;for (int i0; modCount expectedModCount i size; i) {SuppressWarnings(unchecked)final E element (E) elementData[i];if (filter.test(element)) {removeSet.set(i);removeCount;}}if (modCount ! expectedModCount) {throw new ConcurrentModificationException();}// shift surviving elements left over the spaces left by removed elementsfinal boolean anyToRemove removeCount 0;if (anyToRemove) {final int newSize size - removeCount;for (int i0, j0; (i size) (j newSize); i, j) {i removeSet.nextClearBit(i);elementData[j] elementData[i];}for (int knewSize; k size; k) {elementData[k] null; // Let gc do its work}this.size newSize;if (modCount ! expectedModCount) {throw new ConcurrentModificationException();}modCount;}return anyToRemove;}// Predicate 函数式编程参见个人博客 https://blog.csdn.net/jiangyu1013/article/details/103500724OverrideSuppressWarnings(unchecked)public void replaceAll(UnaryOperatorE operator) {Objects.requireNonNull(operator);final int expectedModCount modCount;final int size this.size;for (int i0; modCount expectedModCount i size; i) {elementData[i] operator.apply((E) elementData[i]);}if (modCount ! expectedModCount) {throw new ConcurrentModificationException();}modCount;}OverrideSuppressWarnings(unchecked)public void sort(Comparator? super E c) {final int expectedModCount modCount;Arrays.sort((E[]) elementData, 0, size, c);if (modCount ! expectedModCount) {throw new ConcurrentModificationException();}modCount;}
