From dde621339dab1095108115233651ec2a7e2ea97a Mon Sep 17 00:00:00 2001 From: kyriewhluo Date: Fri, 30 Aug 2024 17:51:14 +0800 Subject: [PATCH] =?UTF-8?q?=E6=96=87=E6=A1=A3=E6=B7=BB=E5=8A=A0=E5=85=B3?= =?UTF-8?q?=E4=BA=8E=E5=AD=97=E7=AC=A6=E4=B8=B2=E3=80=81=E5=AD=97=E8=8A=82?= =?UTF-8?q?=E5=92=8Cvoid=E6=95=B0=E6=8D=AE=E7=B1=BB=E5=9E=8B=E7=9A=84?= =?UTF-8?q?=E8=AF=B4=E6=98=8E?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 在NumPy文档中，常规介绍部分现在包含了关于字符串、字节和void数据类型的信息，以及现有的数值类型。 --- pom.xml | 7 + .../whaifree/dataStructure/PriorityQueue.java | 842 ++++++++++++++++++ .../designPattern/StrategyPattern.java | 129 +++ .../whaifree/leetCode/Array/LeetCode215.java | 15 +- src/main/java/cn/whaifree/test/hashDB.java | 43 + 5 files changed, 1031 insertions(+), 5 deletions(-) create mode 100644 src/main/java/cn/whaifree/dataStructure/PriorityQueue.java diff --git a/pom.xml b/pom.xml index c53e654..1d32cd8 100644 --- a/pom.xml +++ b/pom.xml @@ -18,6 +18,13 @@ + + + org.springframework + spring-context + 5.3.18 + + cglib cglib diff --git a/src/main/java/cn/whaifree/dataStructure/PriorityQueue.java b/src/main/java/cn/whaifree/dataStructure/PriorityQueue.java new file mode 100644 index 0000000..43b113d --- /dev/null +++ b/src/main/java/cn/whaifree/dataStructure/PriorityQueue.java @@ -0,0 +1,842 @@ +package cn.whaifree.dataStructure;/* + * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + + +import java.util.*; + +/** + * An unbounded priority {@linkplain Queue queue} based on a priority heap. + * The elements of the priority queue are ordered according to their + * {@linkplain Comparable natural ordering}, or by a {@link Comparator} + * provided at queue construction time, depending on which constructor is + * used. A priority queue does not permit {@code null} elements. + * A priority queue relying on natural ordering also does not permit + * insertion of non-comparable objects (doing so may result in + * {@code ClassCastException}). + * + *

The head of this queue is the least element + * with respect to the specified ordering. If multiple elements are + * tied for least value, the head is one of those elements -- ties are + * broken arbitrarily. The queue retrieval operations {@code poll}, + * {@code remove}, {@code peek}, and {@code element} access the + * element at the head of the queue. + * + *

A priority queue is unbounded, but has an internal + * capacity governing the size of an array used to store the + * elements on the queue. It is always at least as large as the queue + * size. As elements are added to a priority queue, its capacity + * grows automatically. The details of the growth policy are not + * specified. + * + *

This class and its iterator implement all of the + * optional methods of the {@link Collection} and {@link + * Iterator} interfaces. The Iterator provided in method {@link + * #iterator()} is not guaranteed to traverse the elements of + * the priority queue in any particular order. If you need ordered + * traversal, consider using {@code Arrays.sort(pq.toArray())}. + * + *

Note that this implementation is not synchronized. + * Multiple threads should not access a {@code PriorityQueue} + * instance concurrently if any of the threads modifies the queue. + * Instead, use the thread-safe {@link + * java.util.concurrent.PriorityBlockingQueue} class. + * + *

Implementation note: this implementation provides + * O(log(n)) time for the enqueuing and dequeuing methods + * ({@code offer}, {@code poll}, {@code remove()} and {@code add}); + * linear time for the {@code remove(Object)} and {@code contains(Object)} + * methods; and constant time for the retrieval methods + * ({@code peek}, {@code element}, and {@code size}). + * + *

This class is a member of the + * + * Java Collections Framework. + * + * @since 1.5 + * @author Josh Bloch, Doug Lea + * @param the type of elements held in this collection + */ +class PriorityQueue extends AbstractQueue + implements java.io.Serializable { + + /** + * Inserts the specified element into this priority queue. + * + * @return {@code true} (as specified by {@link Collection#add}) + * @throws ClassCastException if the specified element cannot be + * compared with elements currently in this priority queue + * according to the priority queue's ordering + * @throws NullPointerException if the specified element is null + */ + public boolean add(E e) { + return offer(e); + } + + /** + * Inserts the specified element into this priority queue. + * + * @return {@code true} (as specified by {@link Queue#offer}) + * @throws ClassCastException if the specified element cannot be + * compared with elements currently in this priority queue + * according to the priority queue's ordering + * @throws NullPointerException if the specified element is null + */ + public boolean offer(E e) { + if (e == null) + throw new NullPointerException(); + modCount++; + int i = size; + if (i >= queue.length) + grow(i + 1); + size = i + 1; + if (i == 0) + queue[0] = e; + else + siftUp(i, e); + return true; + } + + @SuppressWarnings("unchecked") + public E peek() { + return (size == 0) ? null : (E) queue[0]; + } + + private int indexOf(Object o) { + if (o != null) { + for (int i = 0; i < size; i++) + if (o.equals(queue[i])) + return i; + } + return -1; + } + + /** + * Removes a single instance of the specified element from this queue, + * if it is present. More formally, removes an element {@code e} such + * that {@code o.equals(e)}, if this queue contains one or more such + * elements. Returns {@code true} if and only if this queue contained + * the specified element (or equivalently, if this queue changed as a + * result of the call). + * + * @param o element to be removed from this queue, if present + * @return {@code true} if this queue changed as a result of the call + */ + public boolean remove(Object o) { + int i = indexOf(o); + if (i == -1) + return false; + else { + removeAt(i); + return true; + } + } + + /** + * Version of remove using reference equality, not equals. + * Needed by iterator.remove. + * + * @param o element to be removed from this queue, if present + * @return {@code true} if removed + */ + boolean removeEq(Object o) { + for (int i = 0; i < size; i++) { + if (o == queue[i]) { + removeAt(i); + return true; + } + } + return false; + } + + /** + * Returns {@code true} if this queue contains the specified element. + * More formally, returns {@code true} if and only if this queue contains + * at least one element {@code e} such that {@code o.equals(e)}. + * + * @param o object to be checked for containment in this queue + * @return {@code true} if this queue contains the specified element + */ + public boolean contains(Object o) { + return indexOf(o) != -1; + } + + /** + * Returns an array containing all of the elements in this queue. + * The elements are in no particular order. + * + *

The returned array will be "safe" in that no references to it are + * maintained by this queue. (In other words, this method must allocate + * a new array). The caller is thus free to modify the returned array. + * + *

This method acts as bridge between array-based and collection-based + * APIs. + * + * @return an array containing all of the elements in this queue + */ + public Object[] toArray() { + return Arrays.copyOf(queue, size); + } + + /** + * Returns an array containing all of the elements in this queue; the + * runtime type of the returned array is that of the specified array. + * The returned array elements are in no particular order. + * If the queue fits in the specified array, it is returned therein. + * Otherwise, a new array is allocated with the runtime type of the + * specified array and the size of this queue. + * + *

If the queue fits in the specified array with room to spare + * (i.e., the array has more elements than the queue), the element in + * the array immediately following the end of the collection is set to + * {@code null}. + * + *

Like the {@link #toArray()} method, this method acts as bridge between + * array-based and collection-based APIs. Further, this method allows + * precise control over the runtime type of the output array, and may, + * under certain circumstances, be used to save allocation costs. + * + *

Suppose {@code x} is a queue known to contain only strings. + * The following code can be used to dump the queue into a newly + * allocated array of {@code String}: + * + * 

 {@code String[] y = x.toArray(new String[0]);}
+ * + * Note that {@code toArray(new Object[0])} is identical in function to + * {@code toArray()}. + * + * @param a the array into which the elements of the queue are to + * be stored, if it is big enough; otherwise, a new array of the + * same runtime type is allocated for this purpose. + * @return an array containing all of the elements in this queue + * @throws ArrayStoreException if the runtime type of the specified array + * is not a supertype of the runtime type of every element in + * this queue + * @throws NullPointerException if the specified array is null + */ + @SuppressWarnings("unchecked") + public T[] toArray(T[] a) { + final int size = this.size; + if (a.length < size) + // Make a new array of a's runtime type, but my contents: + return (T[]) Arrays.copyOf(queue, size, a.getClass()); + System.arraycopy(queue, 0, a, 0, size); + if (a.length > size) + a[size] = null; + return a; + } + + @SuppressWarnings("unchecked") + public E poll() { + if (size == 0) + return null; + int s = --size; + modCount++; + E result = (E) queue[0]; + E x = (E) queue[s]; + queue[s] = null; + if (s != 0) + siftDown(0, x); + return result; + } + + /** + * Removes the ith element from queue. + * + * Normally this method leaves the elements at up to i-1, + * inclusive, untouched. Under these circumstances, it returns + * null. Occasionally, in order to maintain the heap invariant, + * it must swap a later element of the list with one earlier than + * i. Under these circumstances, this method returns the element + * that was previously at the end of the list and is now at some + * position before i. This fact is used by iterator.remove so as to + * avoid missing traversing elements. + */ + @SuppressWarnings("unchecked") + private E removeAt(int i) { + // assert i >= 0 && i < size; + modCount++; + int s = --size; + if (s == i) // removed last element + queue[i] = null; + else { + E moved = (E) queue[s]; + queue[s] = null; + siftDown(i, moved); + if (queue[i] == moved) { + siftUp(i, moved); + if (queue[i] != moved) + return moved; + } + } + return null; + } + + /** + * Inserts item x at position k, maintaining heap invariant by + * promoting x up the tree until it is greater than or equal to + * its parent, or is the root. + * + * To simplify and speed up coercions and comparisons. the + * Comparable and Comparator versions are separated into different + * methods that are otherwise identical. (Similarly for siftDown.) + * + * 在位置 k 处插入项 x，通过在树中向上提升 x 来保持堆不变，直到它大于或等于其父级或成为根。 + * 简化和加速强制和比较。 + * Comparable 和 Comparator 版本分为不同的方法，这些方法在其他方面是相同的。（siftDown 也是如此。 + * + * @param k the position to fill + * @param x the item to insert + */ + private void siftUp(int k, E x) { + if (comparator != null) + siftUpUsingComparator(k, x); + else + siftUpComparable(k, x); + } + + @SuppressWarnings("unchecked") + private void siftUpComparable(int k, E x) { + Comparable key = (Comparable) x; + while (k > 0) { + int parent = (k - 1) >>> 1; + Object e = queue[parent]; + if (key.compareTo((E) e) >= 0) + break; + queue[k] = e; + k = parent; + } + queue[k] = key; + } + + /** + * 在 k 处的某个元素 x ，让其上升到正确的位置。 + * @param k + * @param x + */ + @SuppressWarnings("unchecked") + private void siftUpUsingComparator(int k, E x) { + // 不断调整 k，直到找到合适的位置 + while (k > 0) { + int parent = (k - 1) >>> 1; // 父节点 无符号右移动 /2 + Object e = queue[parent]; + if (comparator.compare(x, (E) e) >= 0) // 如果优先级比父节点大，直接退出。表示已经到了合适的位置 + // 如大顶堆中 7 3 4 插入 2 第一次就到了合适的位置 7 3 4 2 + // 7 3 4 5 --- > 7 5 4 3 (5比父节点大，替换上去) + break; + queue[k] = e; + k = parent; + } + queue[k] = x; // 将 k 调整到了合适的位置 + } + + /** + * Inserts item x at position k, maintaining heap invariant by + * demoting x down the tree repeatedly until it is less than or + * equal to its children or is a leaf. + * + * @param k the position to fill + * @param x the item to insert + */ + private void siftDown(int k, E x) { + if (comparator != null) + siftDownUsingComparator(k, x); + else + siftDownComparable(k, x); + } + + @SuppressWarnings("unchecked") + private void siftDownComparable(int k, E x) { + Comparable key = (Comparable)x; + int half = size >>> 1; // loop while a non-leaf + while (k < half) { + int child = (k << 1) + 1; // assume left child is least + Object c = queue[child]; + int right = child + 1; + if (right < size && + ((Comparable) c).compareTo((E) queue[right]) > 0) + c = queue[child = right]; + if (key.compareTo((E) c) <= 0) + break; + queue[k] = c; + k = child; + } + queue[k] = key; + } + + @SuppressWarnings("unchecked") + private void siftDownUsingComparator(int k, E x) { + int half = size >>> 1; + while (k < half) { + int child = (k << 1) + 1; + Object c = queue[child]; + int right = child + 1; + if (right < size && + comparator.compare((E) c, (E) queue[right]) > 0) + c = queue[child = right]; + if (comparator.compare(x, (E) c) <= 0) + break; + queue[k] = c; + k = child; + } + queue[k] = x; + } + + /** + * Establishes the heap invariant (described above) in the entire tree, + * assuming nothing about the order of the elements prior to the call. + */ + @SuppressWarnings("unchecked") + private void heapify() { + for (int i = (size >>> 1) - 1; i >= 0; i--) + siftDown(i, (E) queue[i]); + } + + + private static final long serialVersionUID = -7720805057305804111L; + + private static final int DEFAULT_INITIAL_CAPACITY = 11; + + transient Object[] queue; // non-private to simplify nested class access + + private int size = 0; + + private final Comparator comparator; + + /** + * The number of times this priority queue has been + * structurally modified. See AbstractList for gory details. + */ + transient int modCount = 0; // non-private to simplify nested class access + + /** + * Creates a {@code PriorityQueue} with the default initial + * capacity (11) that orders its elements according to their + * {@linkplain Comparable natural ordering}. + */ + public PriorityQueue() { + this(DEFAULT_INITIAL_CAPACITY, null); + } + + public PriorityQueue(int initialCapacity) { + this(initialCapacity, null); + } + + public PriorityQueue(Comparator comparator) { + this(DEFAULT_INITIAL_CAPACITY, comparator); + } + + public PriorityQueue(int initialCapacity, + Comparator comparator) { + // Note: This restriction of at least one is not actually needed, + // but continues for 1.5 compatibility + if (initialCapacity < 1) + throw new IllegalArgumentException(); + this.queue = new Object[initialCapacity]; + this.comparator = comparator; + } + + + @SuppressWarnings("unchecked") + public PriorityQueue(Collection c) { + if (c instanceof SortedSet) { + SortedSet ss = (SortedSet) c; + this.comparator = (Comparator) ss.comparator(); + initElementsFromCollection(ss); + } + else if (c instanceof PriorityQueue) { + PriorityQueue pq = (PriorityQueue) c; + this.comparator = (Comparator) pq.comparator(); + initFromPriorityQueue(pq); + } + else { + this.comparator = null; + initFromCollection(c); + } + } + + /** + * Creates a {@code PriorityQueue} containing the elements in the + * specified priority queue. This priority queue will be + * ordered according to the same ordering as the given priority + * queue. + * + * @param c the priority queue whose elements are to be placed + * into this priority queue + * @throws ClassCastException if elements of {@code c} cannot be + * compared to one another according to {@code c}'s + * ordering + * @throws NullPointerException if the specified priority queue or any + * of its elements are null + */ + @SuppressWarnings("unchecked") + public PriorityQueue(PriorityQueue c) { + this.comparator = (Comparator) c.comparator(); + initFromPriorityQueue(c); + } + + @SuppressWarnings("unchecked") + public PriorityQueue(SortedSet c) { + this.comparator = (Comparator) c.comparator(); + initElementsFromCollection(c); + } + + private void initFromPriorityQueue(PriorityQueue c) { + if (c.getClass() == PriorityQueue.class) { + this.queue = c.toArray(); + this.size = c.size(); + } else { + initFromCollection(c); + } + } + + private void initElementsFromCollection(Collection c) { + Object[] a = c.toArray(); + if (c.getClass() != ArrayList.class) + a = Arrays.copyOf(a, a.length, Object[].class); + int len = a.length; + if (len == 1 || this.comparator != null) + for (int i = 0; i < len; i++) + if (a[i] == null) + throw new NullPointerException(); + this.queue = a; + this.size = a.length; + } + + private void initFromCollection(Collection c) { + initElementsFromCollection(c); + heapify(); + } + + /** + * The maximum size of array to allocate. + * Some VMs reserve some header words in an array. + * Attempts to allocate larger arrays may result in + * OutOfMemoryError: Requested array size exceeds VM limit + */ + private static final int MAX_ARRAY_SIZE = Integer.MAX_VALUE - 8; + + /** + * Increases the capacity of the array. + * + * @param minCapacity the desired minimum capacity + */ + private void grow(int minCapacity) { + int oldCapacity = queue.length; + // Double size if small; else grow by 50% + int newCapacity = oldCapacity + ((oldCapacity < 64) ? + (oldCapacity + 2) : + (oldCapacity >> 1)); + // overflow-conscious code + if (newCapacity - MAX_ARRAY_SIZE > 0) + newCapacity = hugeCapacity(minCapacity); + queue = Arrays.copyOf(queue, newCapacity); + } + + private static int hugeCapacity(int minCapacity) { + if (minCapacity < 0) // overflow + throw new OutOfMemoryError(); + return (minCapacity > MAX_ARRAY_SIZE) ? + Integer.MAX_VALUE : + MAX_ARRAY_SIZE; + } + + + + /** + * Returns an iterator over the elements in this queue. The iterator + * does not return the elements in any particular order. + * + * @return an iterator over the elements in this queue + */ + public Iterator iterator() { + return new Itr(); + } + + private final class Itr implements Iterator { + /** + * Index (into queue array) of element to be returned by + * subsequent call to next. + */ + private int cursor = 0; + + /** + * Index of element returned by most recent call to next, + * unless that element came from the forgetMeNot list. + * Set to -1 if element is deleted by a call to remove. + */ + private int lastRet = -1; + + /** + * A queue of elements that were moved from the unvisited portion of + * the heap into the visited portion as a result of "unlucky" element + * removals during the iteration. (Unlucky element removals are those + * that require a siftup instead of a siftdown.) We must visit all of + * the elements in this list to complete the iteration. We do this + * after we've completed the "normal" iteration. + * + * We expect that most iterations, even those involving removals, + * will not need to store elements in this field. + */ + private ArrayDeque forgetMeNot = null; + + /** + * Element returned by the most recent call to next iff that + * element was drawn from the forgetMeNot list. + */ + private E lastRetElt = null; + + /** + * The modCount value that the iterator believes that the backing + * Queue should have. If this expectation is violated, the iterator + * has detected concurrent modification. + */ + private int expectedModCount = modCount; + + public boolean hasNext() { + return cursor < size || + (forgetMeNot != null && !forgetMeNot.isEmpty()); + } + + @SuppressWarnings("unchecked") + public E next() { + if (expectedModCount != modCount) + throw new ConcurrentModificationException(); + if (cursor < size) + return (E) queue[lastRet = cursor++]; + if (forgetMeNot != null) { + lastRet = -1; + lastRetElt = forgetMeNot.poll(); + if (lastRetElt != null) + return lastRetElt; + } + throw new NoSuchElementException(); + } + + public void remove() { + if (expectedModCount != modCount) + throw new ConcurrentModificationException(); + if (lastRet != -1) { + E moved = PriorityQueue.this.removeAt(lastRet); + lastRet = -1; + if (moved == null) + cursor--; + else { + if (forgetMeNot == null) + forgetMeNot = new ArrayDeque<>(); + forgetMeNot.add(moved); + } + } else if (lastRetElt != null) { + PriorityQueue.this.removeEq(lastRetElt); + lastRetElt = null; + } else { + throw new IllegalStateException(); + } + expectedModCount = modCount; + } + } + + public int size() { + return size; + } + + /** + * Removes all of the elements from this priority queue. + * The queue will be empty after this call returns. + */ + public void clear() { + modCount++; + for (int i = 0; i < size; i++) + queue[i] = null; + size = 0; + } + + /** + * Returns the comparator used to order the elements in this + * queue, or {@code null} if this queue is sorted according to + * the {@linkplain Comparable natural ordering} of its elements. + * + * @return the comparator used to order this queue, or + * {@code null} if this queue is sorted according to the + * natural ordering of its elements + */ + public Comparator comparator() { + return comparator; + } + + /** + * Saves this queue to a stream (that is, serializes it). + * + * @serialData The length of the array backing the instance is + * emitted (int), followed by all of its elements + * (each an {@code Object}) in the proper order. + * @param s the stream + */ + private void writeObject(java.io.ObjectOutputStream s) + throws java.io.IOException { + // Write out element count, and any hidden stuff + s.defaultWriteObject(); + + // Write out array length, for compatibility with 1.5 version + s.writeInt(Math.max(2, size + 1)); + + // Write out all elements in the "proper order". + for (int i = 0; i < size; i++) + s.writeObject(queue[i]); + } + + /** + * Reconstitutes the {@code PriorityQueue} instance from a stream + * (that is, deserializes it). + * + * @param s the stream + */ + private void readObject(java.io.ObjectInputStream s) + throws java.io.IOException, ClassNotFoundException { + // Read in size, and any hidden stuff + s.defaultReadObject(); + + // Read in (and discard) array length + s.readInt(); + +// SharedSecrets.getJavaOISAccess().checkArray(s, Object[].class, size); + queue = new Object[size]; + + // Read in all elements. + for (int i = 0; i < size; i++) + queue[i] = s.readObject(); + + // Elements are guaranteed to be in "proper order", but the + // spec has never explained what that might be. + heapify(); + } + +// /** +// * Creates a late-binding +// * and fail-fast {@link Spliterator} over the elements in this +// * queue. +// * +// *

The {@code Spliterator} reports {@link Spliterator#SIZED}, +// * {@link Spliterator#SUBSIZED}, and {@link Spliterator#NONNULL}. +// * Overriding implementations should document the reporting of additional +// * characteristic values. +// * +// * @return a {@code Spliterator} over the elements in this queue +// * @since 1.8 +// */ +// public final Spliterator spliterator() { +// return new PriorityQueueSpliterator(this, 0, -1, 0); +// } + +// static final class PriorityQueueSpliterator implements Spliterator { +// /* +// * This is very similar to ArrayList Spliterator, except for +// * extra null checks. +// */ +// private final PriorityQueue pq; +// private int index; // current index, modified on advance/split +// private int fence; // -1 until first use +// private int expectedModCount; // initialized when fence set +// +// /** Creates new spliterator covering the given range */ +// PriorityQueueSpliterator(PriorityQueue pq, int origin, int fence, +// int expectedModCount) { +// this.pq = pq; +// this.index = origin; +// this.fence = fence; +// this.expectedModCount = expectedModCount; +// } +// +// private int getFence() { // initialize fence to size on first use +// int hi; +// if ((hi = fence) < 0) { +// expectedModCount = pq.modCount; +// hi = fence = pq.size; +// } +// return hi; +// } +// +// public PriorityQueueSpliterator trySplit() { +// int hi = getFence(), lo = index, mid = (lo + hi) >>> 1; +// return (lo >= mid) ? null : +// new PriorityQueueSpliterator(pq, lo, index = mid, +// expectedModCount); +// } +// +// @SuppressWarnings("unchecked") +// public void forEachRemaining(Consumer action) { +// int i, hi, mc; // hoist accesses and checks from loop +// PriorityQueue q; Object[] a; +// if (action == null) +// throw new NullPointerException(); +// if ((q = pq) != null && (a = q.queue) != null) { +// if ((hi = fence) < 0) { +// mc = q.modCount; +// hi = q.size; +// } +// else +// mc = expectedModCount; +// if ((i = index) >= 0 && (index = hi) <= a.length) { +// for (E e;; ++i) { +// if (i < hi) { +// if ((e = (E) a[i]) == null) // must be CME +// break; +// action.accept(e); +// } +// else if (q.modCount != mc) +// break; +// else +// return; +// } +// } +// } +// throw new ConcurrentModificationException(); +// } +// +// public boolean tryAdvance(Consumer action) { +// if (action == null) +// throw new NullPointerException(); +// int hi = getFence(), lo = index; +// if (lo >= 0 && lo < hi) { +// index = lo + 1; +// @SuppressWarnings("unchecked") E e = (E)pq.queue[lo]; +// if (e == null) +// throw new ConcurrentModificationException(); +// action.accept(e); +// if (pq.modCount != expectedModCount) +// throw new ConcurrentModificationException(); +// return true; +// } +// return false; +// } +// +// public long estimateSize() { +// return (long) (getFence() - index); +// } +// +// public int characteristics() { +// return Spliterator.SIZED | Spliterator.SUBSIZED | Spliterator.NONNULL; +// } +// } +} diff --git a/src/main/java/cn/whaifree/designPattern/StrategyPattern.java b/src/main/java/cn/whaifree/designPattern/StrategyPattern.java index 42b4c27..9ba07c4 100644 --- a/src/main/java/cn/whaifree/designPattern/StrategyPattern.java +++ b/src/main/java/cn/whaifree/designPattern/StrategyPattern.java @@ -1,5 +1,10 @@ package cn.whaifree.designPattern; +import org.springframework.beans.factory.annotation.Autowired; +import org.springframework.stereotype.Component; + +import java.util.concurrent.ConcurrentHashMap; + public class StrategyPattern { enum PayType{ @@ -64,3 +69,127 @@ public class StrategyPattern { new PayService().pay(2); } } + + +/** + * 在 springboot 中使用策略模式 + * + * 1. 使用 Map将接口转为 Map + * 2. 根据 Opr 在 Context 中操作 + * + * 优点：新增操作只要加 类、操作（开闭，扩展开、修改闭），而不用修改原始代码 ifelse 这样 + * 每个操作独立，不影响其他操作 + * + */ +@Component +class Opr{ + @Autowired + private OperationContext context; + + + enum OprEnum{ + FAVOR(1), + COMMENT(2), + ; + int oprNum = 0; + + OprEnum(int oprNum) { + this.oprNum = oprNum; + } + } + + interface BlogOperation{ + void operation(String data); + } + + @Component + static class FavorOperation implements BlogOperation{ + @Override + public void operation(String data) { + // 操作数据库 + System.out.println("点赞" + data); + } + } + + @Component + static class CommentOperation implements BlogOperation{ + @Override + public void operation(String data) { + // 操作数据库 + System.out.println("评论" + data); + } + } + + @Component + static class OperationContext{ + private ConcurrentHashMap map = null; + + /** + * + * @param blogOperationConcurrentHashMap + */ + @Autowired + public OperationContext(ConcurrentHashMap blogOperationConcurrentHashMap) { + map = new ConcurrentHashMap<>(); + map.put(OprEnum.FAVOR, blogOperationConcurrentHashMap.get("favorOperation")); + map.put(OprEnum.COMMENT, blogOperationConcurrentHashMap.get("commentOperation")); + } + + public void opr(BlogOperation blogOperation, String data) { + BlogOperation opr = map.get(blogOperation); + opr.operation(data); + } + + } + + +} + +enum OperationEnum{ + + FAVOUR(1, "点赞", new Operation() { + @Override + public Object action(OperationEnum operationEnum) { + + return null; + } + }), + COMMENT(2,"评论", new Operation() { + @Override + public Object action(OperationEnum operationEnum) { + return null; + } + }); + + + int code; + String oprName; + Operation oprExecution; + + + OperationEnum(int code, String oprName, Operation operation) { + this.code = code; + this.oprName = oprName; + this.oprExecution = operation; + } + + +} + +interface Operation{ + Object action(OperationEnum operationEnum); +} + + + +class HiShareStrategyPattern{ + + + + public static void main(String[] args) { + + } +} + + + diff --git a/src/main/java/cn/whaifree/leetCode/Array/LeetCode215.java b/src/main/java/cn/whaifree/leetCode/Array/LeetCode215.java index 8af6b16..dfda3d9 100644 --- a/src/main/java/cn/whaifree/leetCode/Array/LeetCode215.java +++ b/src/main/java/cn/whaifree/leetCode/Array/LeetCode215.java @@ -12,11 +12,16 @@ public class LeetCode215 { @Test public void main() { - int[] nums = {3,2,1,5,6,4}; - int k = 2; - Solution solution = new Solution(); - int i = solution.findKthLargest(nums, k); - System.out.println(i); + int i = 0; + while (true) { + i++; + } +// +// int[] nums = {3,2,1,5,6,4}; +// int k = 2; +// Solution solution = new Solution(); +// int i = solution.findKthLargest(nums, k); +// System.out.println(i); } class Solution { diff --git a/src/main/java/cn/whaifree/test/hashDB.java b/src/main/java/cn/whaifree/test/hashDB.java index 249ca6f..edef646 100644 --- a/src/main/java/cn/whaifree/test/hashDB.java +++ b/src/main/java/cn/whaifree/test/hashDB.java @@ -1,5 +1,9 @@ package cn.whaifree.test; +import java.util.ArrayList; +import java.util.ConcurrentModificationException; +import java.util.ListIterator; + /** * @version 1.0 * @Author whai文海 @@ -41,3 +45,42 @@ public class hashDB { } + +class test{ + + public static void main(String[] args) { + ArrayList sharedList= new ArrayList<>(); + + new Thread(() -> { + try { + for (int i = 0; i < 10; i++) { + sharedList.add("Item " + i); + // 模拟一些工作时间 + Thread.sleep(50); + } + } catch (InterruptedException e) { + Thread.currentThread().interrupt(); + System.out.println("Thread was interrupted."); + } + }).start(); + + + new Thread(() -> { + try { + ListIterator iterator = sharedList.listIterator(); + while (iterator.hasNext()) { + System.out.println(iterator.next()); + // 模拟一些工作时间 + Thread.sleep(100); + } + } catch (ConcurrentModificationException e) { + System.out.println("Caught ConcurrentModificationException during iteration."); + } catch (InterruptedException e) { + Thread.currentThread().interrupt(); + System.out.println("Thread was interrupted."); + } + }).start(); + + + } +}