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package com.foxinmy.weixin4j.util;

/*
 * Copyright (c) 2008-2014 MongoDB, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.net.NetworkInterface;
import java.nio.ByteBuffer;
import java.util.Date;
import java.util.Enumeration;
import java.util.Random;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * 

* A globally unique identifier for objects. *

* *

* Consists of 12 bytes, divided as follows: *

* * * * * * * * * * * * * * * * * * * * * * *
ObjectID layout
01234567891011
timemachinepidinc
* *

* Instances of this class are immutable. *

* * @mongodb.driver.manual core/object-id ObjectId */ public class ObjectId implements Comparable, java.io.Serializable { private static final long serialVersionUID = -4415279469780082174L; static final Logger LOGGER = Logger.getLogger("org.bson.ObjectId"); /** * Gets a new object id. * * @return the new id */ public static ObjectId get() { return new ObjectId(); } /** * Checks if a string could be an {@code ObjectId}. * * @param s * a potential ObjectId as a String. * @return whether the string could be an object id * @throws IllegalArgumentException * if hexString is null */ public static boolean isValid(String s) { if (s == null) return false; final int len = s.length(); if (len != 24) return false; for (int i = 0; i < len; i++) { char c = s.charAt(i); if (c >= '0' && c <= '9') continue; if (c >= 'a' && c <= 'f') continue; if (c >= 'A' && c <= 'F') continue; return false; } return true; } /** * Constructs an ObjectId given its 12-byte binary representation. * * @param b * a byte array of length 12 */ public ObjectId(byte[] b) { if (b.length != 12) throw new IllegalArgumentException("need 12 bytes"); ByteBuffer bb = ByteBuffer.wrap(b); _time = bb.getInt(); _machine = bb.getInt(); _inc = bb.getInt(); _new = false; } /** * Create a new object id. */ public ObjectId() { _time = (int) (System.currentTimeMillis() / 1000); _machine = _genmachine; _inc = _nextInc.getAndIncrement(); _new = true; } @Override public int hashCode() { int x = _time; x += (_machine * 111); x += (_inc * 17); return x; } @Override public boolean equals(Object o) { if (this == o) return true; if (!(o instanceof ObjectId)) { return false; } ObjectId other = (ObjectId) o; return _time == other._time && _machine == other._machine && _inc == other._inc; } /** * Converts this instance into a 24-byte hexadecimal string representation. * * @return a string representation of the ObjectId in hexadecimal format */ public String toHexString() { final StringBuilder buf = new StringBuilder(24); for (final byte b : toByteArray()) { buf.append(String.format("%02x", b & 0xff)); } return buf.toString(); } /** * Convert to a byte array. Note that the numbers are stored in big-endian * order. * * @return the byte array */ public byte[] toByteArray() { byte b[] = new byte[12]; ByteBuffer bb = ByteBuffer.wrap(b); // by default BB is big endian like we need bb.putInt(_time); bb.putInt(_machine); bb.putInt(_inc); return b; } static String _pos(String s, int p) { return s.substring(p * 2, (p * 2) + 2); } public String toString() { byte b[] = toByteArray(); StringBuilder buf = new StringBuilder(24); for (int i = 0; i < b.length; i++) { int x = b[i] & 0xFF; String s = Integer.toHexString(x); if (s.length() == 1) buf.append("0"); buf.append(s); } return buf.toString(); } int _compareUnsigned(int i, int j) { long li = 0xFFFFFFFFL; li = i & li; long lj = 0xFFFFFFFFL; lj = j & lj; long diff = li - lj; if (diff < Integer.MIN_VALUE) return Integer.MIN_VALUE; if (diff > Integer.MAX_VALUE) return Integer.MAX_VALUE; return (int) diff; } public int compareTo(ObjectId id) { if (id == null) return -1; int x = _compareUnsigned(_time, id._time); if (x != 0) return x; x = _compareUnsigned(_machine, id._machine); if (x != 0) return x; return _compareUnsigned(_inc, id._inc); } /** * Gets the timestamp (number of seconds since the Unix epoch). * * @return the timestamp */ public int getTimestamp() { return _time; } /** * Gets the timestamp as a {@code Date} instance. * * @return the Date */ public Date getDate() { return new Date(_time * 1000L); } /** * Gets the current value of the auto-incrementing counter. * * @return the current counter value. */ public static int getCurrentCounter() { return _nextInc.get(); } final int _time; final int _machine; final int _inc; boolean _new; private static AtomicInteger _nextInc = new AtomicInteger( (new java.util.Random()).nextInt()); private static final int _genmachine; static { try { // build a 2-byte machine piece based on NICs info int machinePiece; { try { StringBuilder sb = new StringBuilder(); Enumeration e = NetworkInterface .getNetworkInterfaces(); while (e.hasMoreElements()) { NetworkInterface ni = e.nextElement(); sb.append(ni.toString()); } machinePiece = sb.toString().hashCode() << 16; } catch (Throwable e) { // exception sometimes happens with IBM JVM, use random LOGGER.log(Level.WARNING, e.getMessage(), e); machinePiece = (new Random().nextInt()) << 16; } LOGGER.fine("machine piece post: " + Integer.toHexString(machinePiece)); } // add a 2 byte process piece. It must represent not only the JVM // but the class loader. // Since static var belong to class loader there could be collisions // otherwise final int processPiece; { int processId = new java.util.Random().nextInt(); try { processId = java.lang.management.ManagementFactory .getRuntimeMXBean().getName().hashCode(); } catch (Throwable t) { } ClassLoader loader = ObjectId.class.getClassLoader(); int loaderId = loader != null ? System.identityHashCode(loader) : 0; StringBuilder sb = new StringBuilder(); sb.append(Integer.toHexString(processId)); sb.append(Integer.toHexString(loaderId)); processPiece = sb.toString().hashCode() & 0xFFFF; LOGGER.fine("process piece: " + Integer.toHexString(processPiece)); } _genmachine = machinePiece | processPiece; LOGGER.fine("machine : " + Integer.toHexString(_genmachine)); } catch (Exception e) { throw new RuntimeException(e); } } }




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