SmartEngine:SmartEngine是轻型业务编排引擎

/* Copyright (c) 2008, Nathan Sweet * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided with the distribution. * - Neither the name of Esoteric Software nor the names of its contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT * SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package com.alibaba.smart.framework.engine.common.util; import java.util.ArrayList; import java.util.Iterator; import java.util.NoSuchElementException; import java.util.Random; /** An unordered map. This implementation is a cuckoo hash map using 3 hashes (if table size is less than 2^16) or 4 hashes * (if table size is greater than or equal to 2^16), random walking, and a small stash for problematic keys Null keys are not * allowed. Null values are allowed. No allocation is done except when growing the table size. <br> * <br> * This map performs very fast get, containsKey, and remove (typically O(1), worst case O(log(n))). Put may be a bit slower, * depending on hash collisions. Load factors greater than 0.91 greatly increase the chances the map will have to rehash to the * next higher POT size. * @author Nathan Sweet */ public class ObjectMap<K, V> { // primes for hash functions 2, 3, and 4 private static final int PRIME2 = 0xbe1f14b1; private static final int PRIME3 = 0xb4b82e39; private static final int PRIME4 = 0xced1c241; static Random random = new Random(); public int size; K[] keyTable; V[] valueTable; int capacity, stashSize; private float loadFactor; private int hashShift, mask, threshold; private int stashCapacity; private int pushIterations; private boolean isBigTable; /** Creates a new map with an initial capacity of 32 and a load factor of 0.8. This map will hold 25 items before growing the * backing table. */ public ObjectMap () { this(32, 0.8f); } /** Creates a new map with a load factor of 0.8. This map will hold initialCapacity * 0.8 items before growing the backing * table. */ public ObjectMap (int initialCapacity) { this(initialCapacity, 0.8f); } /** Creates a new map with the specified initial capacity and load factor. This map will hold initialCapacity * loadFactor items * before growing the backing table. */ public ObjectMap (int initialCapacity, float loadFactor) { if (initialCapacity < 0) throw new IllegalArgumentException("initialCapacity must be >= 0: " + initialCapacity); if (initialCapacity > 1 << 30) throw new IllegalArgumentException("initialCapacity is too large: " + initialCapacity); capacity = nextPowerOfTwo(initialCapacity); if (loadFactor <= 0) throw new IllegalArgumentException("loadFactor must be > 0: " + loadFactor); this.loadFactor = loadFactor; // big table is when capacity >= 2^16 isBigTable = (capacity >>> 16) != 0 ? true : false; threshold = (int)(capacity * loadFactor); mask = capacity - 1; hashShift = 31 - Integer.numberOfTrailingZeros(capacity); stashCapacity = Math.max(3, (int)Math.ceil(Math.log(capacity)) * 2); pushIterations = Math.max(Math.min(capacity, 8), (int)Math.sqrt(capacity) / 8); keyTable = (K[])new Object[capacity + stashCapacity]; valueTable = (V[])new Object[keyTable.length]; } /** Creates a new map identical to the specified map. */ public ObjectMap (ObjectMap<? extends K, ? extends V> map) { this(map.capacity, map.loadFactor); stashSize = map.stashSize; System.arraycopy(map.keyTable, 0, keyTable, 0, map.keyTable.length); System.arraycopy(map.valueTable, 0, valueTable, 0, map.valueTable.length); size = map.size; } /** Returns the old value associated with the specified key, or null. */ public V put (K key, V value) { if (key == null) throw new IllegalArgumentException("key cannot be null."); return put_internal(key, value); } private V put_internal (K key, V value) { // avoid getfield opcode K[] keyTable = this.keyTable; int mask = this.mask; boolean isBigTable = this.isBigTable; // Check for existing keys. int hashCode = key.hashCode(); int index1 = hashCode & mask; K key1 = keyTable[index1]; if (key.equals(key1)) { V oldValue = valueTable[index1]; valueTable[index1] = value; return oldValue; } int index2 = hash2(hashCode); K key2 = keyTable[index2]; if (key.equals(key2)) { V oldValue = valueTable[index2]; valueTable[index2] = value; return oldValue; } int index3 = hash3(hashCode); K key3 = keyTable[index3]; if (key.equals(key3)) { V oldValue = valueTable[index3]; valueTable[index3] = value; return oldValue; } int index4 = -1; K key4 = null; if (isBigTable) { index4 = hash4(hashCode); key4 = keyTable[index4]; if (key.equals(key4)) { V oldValue = valueTable[index4]; valueTable[index4] = value; return oldValue; } } // Update key in the stash. for (int i = capacity, n = i + stashSize; i < n; i++) { if (key.equals(keyTable[i])) { V oldValue = valueTable[i]; valueTable[i] = value; return oldValue; } } // Check for empty buckets. if (key1 == null) { keyTable[index1] = key; valueTable[index1] = value; if (size++ >= threshold) resize(capacity << 1); return null; } if (key2 == null) { keyTable[index2] = key; valueTable[index2] = value; if (size++ >= threshold) resize(capacity << 1); return null; } if (key3 == null) { keyTable[index3] = key; valueTable[index3] = value; if (size++ >= threshold) resize(capacity << 1); return null; } if (isBigTable && key4 == null) { keyTable[index4] = key; valueTable[index4] = value; if (size++ >= threshold) resize(capacity << 1); return null; } push(key, value, index1, key1, index2, key2, index3, key3, index4, key4); return null; } public void putAll (ObjectMap<K, V> map) { ensureCapacity(map.size); for (Entry<K, V> entry : map.entries()) put(entry.key, entry.value); } /** Skips checks for existing keys. */ private void putResize (K key, V value) { // Check for empty buckets. int hashCode = key.hashCode(); int index1 = hashCode & mask; K key1 = keyTable[index1]; if (key1 == null) { keyTable[index1] = key; valueTable[index1] = value; if (size++ >= threshold) resize(capacity << 1); return; } int index2 = hash2(hashCode); K key2 = keyTable[index2]; if (key2 == null) { keyTable[index2] = key; valueTable[index2] = value; if (size++ >= threshold) resize(capacity << 1); return; } int index3 = hash3(hashCode); K key3 = keyTable[index3]; if (key3 == null) { keyTable[index3] = key; valueTable[index3] = value; if (size++ >= threshold) resize(capacity << 1); return; } int index4 = -1; K key4 = null; if (isBigTable) { index4 = hash4(hashCode); key4 = keyTable[index4]; if (key4 ==