IPV6离线地址库Java版(极致性能，无内存分配，申请了专利)

devtools/2025/1/12 0:54:51/

IPV6版本的技术含量就比V4版本的高了很多，当时还申请了技术专利的，也一样贴给大家看看。

IPV6离线数据包构建

java">package com.bob.common.utils.ip.v6;import java.io.ByteArrayInputStream;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;import com.alibaba.fastjson.JSON;import com.bob.common.utils.ip.IpGeoMetaInfo;
import com.google.common.collect.Lists;
import org.apache.commons.codec.digest.DigestUtils;/*** @author jjb318191* @create 2020-04-30 9:40*/
public class Ipv6IndexProcessor {private byte[] data;/*** 每个长度字节的ip数量*/private int[] blockIpNum;/*** 相同ip前缀的ip起始序号, 在相同长度内部的序号*/private List<int[]> ipBlockStartIndex;/*** 相同ip前缀的ip结束序号, 在相同长度内部的序号*/private List<int[]> ipBlockEndIndex;/*** 不同字节长度的ip信息,ip差值,内容位置*/private List<List<Byte>> diffLengthIpInfos;/*** 内容*/private List<String> contents;/*** 内容的位置和长度* key: 内容* value: {@link #contents}位置*/private Map<String, Integer> contentMapping;private int contentLength;/*** 内容字符编码*/private static final String CONTENT_CHAR_SET = "utf-8";/*** 元数据的字节长度*/private static final int META_INFO_BYTE_LENGTH = 1024;/*** IP前缀分片个数*/private static final int IP_FIRST_SEGMENT_SIZE = 256 * 256;public boolean init() {this.blockIpNum = new int[16];this.ipBlockStartIndex = new ArrayList<>(16);this.ipBlockEndIndex = new ArrayList<>(16);this.diffLengthIpInfos = new ArrayList(16);for (int i = 0; i < 16; i++) {int[] ints1 = new int[IP_FIRST_SEGMENT_SIZE];Arrays.fill(ints1, -1);ipBlockStartIndex.add(ints1);int[] ints2 = new int[IP_FIRST_SEGMENT_SIZE];Arrays.fill(ints2, -1);ipBlockEndIndex.add(ints2);diffLengthIpInfos.add(new ArrayList<>());}this.contents = new ArrayList<>(1 << 14);this.contentMapping = new HashMap<>(1 << 14);return true;}public void index(String s, String e, String content) {byte[] startIp = new BigInteger(s).toByteArray();byte[] endIp = new BigInteger(e).toByteArray();int length = endIp.length;// 补充startIp长度if (startIp.length != length) {int l = startIp.length;byte[] bytes = new byte[length];System.arraycopy(startIp, 0, bytes, length - l, l);startIp = bytes;}// 有效字节长度int effectiveBytesLength = endIp[0] != 0 ? length : calculateEffectiveLength(endIp);int index = effectiveBytesLength - 1;// 有效首字节位置// ip首段, 比如 1.2.6.5, 首段是 1.2, 位置 1*256+2 = 258int startIndex = length - effectiveBytesLength;int segment;if (startIndex == length - 1) {  // 兼容一个字节的ipsegment = endIp[length - 1] & 0xff;} else {segment = (endIp[startIndex] & 0xff) * 256 + (endIp[startIndex + 1] & 0xff);}// 获取当前ip的插入顺序, 比如是7个长度字节的地100个ipint order = blockIpNum[index];// 初始化起始序号, 当前字节长度内的序号int[] startBlock = ipBlockStartIndex.get(index);if (startBlock[segment] == -1) {startBlock[segment] = order;}// 初始化结束序号, 当前字节长度内的序号int[] endBlock = ipBlockEndIndex.get(index);endBlock[segment] = order;// 如果ip在256*256之前if (effectiveBytesLength <= 2) {// 起始ip的段序号int startSegment = effectiveBytesLength == 1 ? startIp[length - 1] & 0xff: (startIp[length - 2] & 0xff) * 256 + (startIp[length - 1] & 0xff);for (int i = startSegment; i < segment; i++) {startBlock[i] = order;endBlock[i] = order;}}// 插入序号自增blockIpNum[index] = ++order;int contentOffset;// 如果这个内容写过了if (contentMapping.containsKey(content)) {// 写内容索引的offsetcontentOffset = contentMapping.get(content);} else {  // 新的内容this.contents.add(content);contentOffset = contents.size() - 1;contentMapping.put(content, contentOffset);}List<Byte> segmentInfo = diffLengthIpInfos.get(index);if (startIndex + 2 < length) {// 写ip后缀listAddArray(segmentInfo, Arrays.copyOfRange(endIp, startIndex + 2, length));// 写ip前缀listAddArray(segmentInfo, Arrays.copyOfRange(startIp, startIndex + 2, length));}// 写内容位置, 默认3个字节listAddArray(segmentInfo, to3ByteArray(contentOffset));}public void finish() throws Exception {// 如果内容数小于 256*256,则用2个字节存储if (contents.size() < 1 << 16) {reduceContentIndexByteLength();}//4个字节的内容总数 + 16种字节长度 * 4 (每种长度下的ip数)// +  16*256*256*8字节 + ...int contentOffset = META_INFO_BYTE_LENGTH + 4 + 16 * 4 + 16 * IP_FIRST_SEGMENT_SIZE * 8+ calculateTotalListSize(diffLengthIpInfos);this.data = new byte[contentOffset + sumIpNum() * 50];// 4字节内容数writeInt(this.data, META_INFO_BYTE_LENGTH, contents.size());// 写入字节长度的ip条数for (int i = 0; i < blockIpNum.length; i++) {writeInt(this.data, META_INFO_BYTE_LENGTH + 4 + i * 4, blockIpNum[i]);}// 把多个字节长度的ip的前缀序号都写入数组int nextOffset = META_INFO_BYTE_LENGTH + 4 + 16 * 4;for (int x = 0; x < 16; x++) {// 写入每个IP前缀的起始ip序号和结束ip序号for (int i = 0; i < IP_FIRST_SEGMENT_SIZE; i++) {writeInt(data, nextOffset, ipBlockStartIndex.get(x)[i]);writeInt(data, nextOffset + 4, ipBlockEndIndex.get(x)[i]);nextOffset += 8;}}// 写ip后缀,ip差值,内容位置for (int i = 0; i < diffLengthIpInfos.size(); i++) {List<Byte> list = diffLengthIpInfos.get(i);arrayAddList(data, list, nextOffset);// 比如6个字节有7000条ip, 写入ip条数nextOffset += list.size();}// 写内容for (String content : contents) {byte[] bytes = content.getBytes(CONTENT_CHAR_SET);writeInt(data, nextOffset, bytes.length);nextOffset += 4;System.arraycopy(bytes, 0, data, nextOffset, bytes.length);nextOffset += bytes.length;}this.contentLength = nextOffset;// 计算MD5IpGeoMetaInfo meta = new IpGeoMetaInfo();meta.setIpversion(6);meta.setChecksum(DigestUtils.md5Hex(new ByteArrayInputStream(data, 0, nextOffset)));String json = JSON.toJSONString(meta);byte[] metaData = json.getBytes(CONTENT_CHAR_SET);int length = metaData.length;// 验证meta长度if (4 + length > META_INFO_BYTE_LENGTH) {throw new IllegalStateException(String.format("meta info length greater than %d , meta info json: %s", META_INFO_BYTE_LENGTH, json));}// 写入meta信息writeInt(data, 0, length);System.arraycopy(metaData, 0, data, 4, length);}private void writeInt(byte[] data, int offset, int i) {writeVLong4(data, offset, i);}/*** 计算字节的有效长度** @param bytes* @return*/private int calculateEffectiveLength(byte[] bytes) {for (int i = 0; i < bytes.length; i++) {if (bytes[i] != 0) {return bytes.length - i;}}return bytes.length;}/*** 缩减内容位置所占字节数*/private void reduceContentIndexByteLength() {for (int i = 0; i < 16; i++) {List<Byte> bytes = diffLengthIpInfos.get(i);if (bytes.isEmpty()) {continue;}int perLength = i < 2 ? 3 : 2 * (i + 1 - 2) + 3;List<Byte> newBytes = new ArrayList<>(bytes.size());List<List<Byte>> partitions = Lists.partition(bytes, perLength);// 缩减内容字节数, 由3字节减为2字节for (List<Byte> bts : partitions) {for (int k = 0; k < bts.size(); k++) {if (k != perLength - 2 - 1) {newBytes.add(bts.get(k));}}}diffLengthIpInfos.remove(i);diffLengthIpInfos.add(i, newBytes);}}/*** 写入4个字节的long** @param data   字节数据* @param offset 偏移量* @param i      值*/private void writeVLong4(byte[] data, int offset, long i) {data[offset++] = (byte)(i >> 24);data[offset++] = (byte)(i >> 16);data[offset++] = (byte)(i >> 8);data[offset] = (byte)i;}private void listAddArray(List<Byte> list, byte[] array) {for (byte t : array) {list.add(t);}}private void arrayAddList(byte[] array, List<Byte> list, int offset) {for (byte b : list) {array[offset++] = b;}}/*** 用3个字节存储int** @param n* @return*/private byte[] to3ByteArray(int n) {byte[] b = new byte[3];b[2] = (byte)(n & 0xff);b[1] = (byte)(n >> 8 & 0xff);b[0] = (byte)(n >> 16 & 0xff);return b;}private int calculateTotalListSize(List<List<Byte>> dataList) {int length = 0;for (List<Byte> list : dataList) {length += list.size();}return length;}private int sumIpNum() {int sum = 0;for (int i : blockIpNum) {sum += i;}return sum;}public byte[] getData() {return this.data;}public int getContentOffset() {return this.contentLength;}}

IPV6数据包加载及检索

java">package com.bob.common.utils.ip.v6;import java.io.File;
import java.util.Arrays;
import java.util.HashSet;import com.bob.common.utils.ip.IpGeoMetaInfo;
import org.apache.commons.io.FileUtils;import static com.bob.common.utils.ip.DigestUtils.rawToJSON;
import static com.bob.common.utils.ip.v4.IPv4BitCalc.readInt;/*** @author jjb318191* @create 2020-04-30 9:44*/
public class Ipv6SearchProcessor {/*** v6 a段索引区占用字节数*/private static final int IP_FIRST_SEGMENT_SIZE = 256 * 256;/*** ipBlockStartIndex[1][128.100] = 1000 : 表示以128.100开头第一个IP段的序号是1000*/private int[][] ipBlockStartIndex;/*** ipBlockStartIndex[128.100] = 1200 : 表示以128.100开始最后一个IP段的序号是1200*/private int[][] ipBlockEndIndex;/*** 不同字节长度的ip信息,ip差值,内容位置*/private byte[][] diffLengthIpInfos;private String[] contentArray;private ThreadLocal<byte[][]> cacheBytePool = new ThreadLocal<>();/*** 内容位置字节长度*/private int contentIndexByteLength;/*** 元数据的字节长度*/private static final int META_INFO_BYTE_LENGTH = 1024;/*** 内容字符编码*/private static final String CONTENT_CHAR_SET = "utf-8";public final boolean load(File file, IpGeoMetaInfo metaInfo) throws Exception {byte[] data = FileUtils.readFileToByteArray(file);// 唯一性的内容条数this.contentArray = new String[readInt(data, META_INFO_BYTE_LENGTH)];// 内容位置占字节数, 内容条数一般3字节足够了this.contentIndexByteLength = contentArray.length < 1 << 16 ? 2 : 3;// 有多少种不同长度就生成多少个字节数组this.diffLengthIpInfos = new byte[16][];this.ipBlockStartIndex = new int[16][];this.ipBlockEndIndex = new int[16][];int offset = META_INFO_BYTE_LENGTH + 4 + 16 * 4;for (int i = 0; i < 16; i++) {// 此字节长度下的ip数int num = readInt(data, META_INFO_BYTE_LENGTH + 4 + i * 4);if (num > 0) {// 2字节的ip： 就存储内容序号// 6字节的ip ： 4字节后缀 + 4字节的ip差值 + 2/3字节的内容序号// 16字节的ip ： 14字节后缀 + 14字节的ip差值 + 2/3字节的内容序号int length = i < 2 ? contentIndexByteLength * num : (2 * (i + 1 - 2) + contentIndexByteLength) * num;this.diffLengthIpInfos[i] = new byte[length];ipBlockStartIndex[i] = new int[IP_FIRST_SEGMENT_SIZE];ipBlockEndIndex[i] = new int[IP_FIRST_SEGMENT_SIZE];}}// 加载每个ip段的起始序号和结束序号for (int i = 0; i < 16; i++) {// 此长度的ip不存在if (diffLengthIpInfos[i] == null) {offset += 8 * IP_FIRST_SEGMENT_SIZE;continue;}for (int j = 0; j < IP_FIRST_SEGMENT_SIZE; j++) {// 0:0:0:0:0:12:2e:3000  :  存储 6字节长度的ip 的 12 开头的ip, 他们的序号在 100~1000之间, 是6字节内部的序号ipBlockStartIndex[i][j] = readInt(data, offset);ipBlockEndIndex[i][j] = readInt(data, offset + 4);offset += 8;}}// 加载每个ip段的数据信息,ip后段, ip差值, 内容位置for (int i = 0; i < diffLengthIpInfos.length; i++) {byte[] bytes = diffLengthIpInfos[i];if (bytes != null) {System.arraycopy(data, offset, bytes, 0, bytes.length);offset += bytes.length;}}// 加载内容for (int i = 0; i < contentArray.length; i++) {int length = readInt(data, offset);offset += 4;// 将所有字符串都取出来, 每个字符串都缓存好String rawContent = new String(Arrays.copyOfRange(data, offset, offset + length), CONTENT_CHAR_SET);String content = rawToJSON(rawContent, Arrays.asList(metaInfo.getStoredProperties()),new HashSet<>(Arrays.asList(metaInfo.getLoadProperties())));contentArray[i] = content;offset += length;}return true;}public final String search(String ip) {// 将ip转换成字节数组byte[] iPv6Address = toByteArray(ip);// 当前字节长度在所有长度中的序号, 从0开始int segmentIndex = iPv6Address.length - 1;// 当前长度下的ip没有if (ipBlockStartIndex[segmentIndex] == null) {return null;}int prefixSegmentsInt;if (iPv6Address.length == 1) {  // 一个字节的ipprefixSegmentsInt = iPv6Address[0] & 0xff;} else {prefixSegmentsInt = ((iPv6Address[0] & 0xff) << 8) + (iPv6Address[1] & 0xff);}int start = ipBlockStartIndex[segmentIndex][prefixSegmentsInt];int end = ipBlockEndIndex[segmentIndex][prefixSegmentsInt];if (start < 0) {return null;}int cur = binarySearch(start, end, iPv6Address);// ip地址未分配if (cur == -1) {return null;}return contentArray[cur];}/*** 定位ip序号** @param low  ip段的起始序号* @param high ip段的结束序号* @param ip   IP字节数组, 16字节* @return int*/private int binarySearch(int low, int high, byte[] ip) {// 存储当前长度的ip信息的数组byte[] data = diffLengthIpInfos[ip.length - 1];// 如果是一字节或者二字节的ipif (ip.length <= 2) {return readVInt(data, high * contentIndexByteLength, contentIndexByteLength);}// 每份ip信息的字节长度int perLength = ((ip.length - 2) << 1) + contentIndexByteLength;int result = -2, order = high;while (low <= high) {int mid = (low + high) >> 1;result = compareByteArray(data, mid * perLength, ip, 2);// 如果结束的ip就是当前ipif (result == 0) {order = mid;break;} else if (result > 0) {order = mid;if (mid == 0) {break;}high = mid - 1;} else {low = mid + 1;}}int offset = order * perLength;if (result != 0 && !compareByStartIp(ip, 2, data, offset + ip.length - 2)) {return -1;}return readVInt(data, offset + ((ip.length - 2) << 1), contentIndexByteLength);}/*** 读取3个字节凑成Int** @param data* @param p* @return*/private int readVInt(byte[] data, int p, int length) {if (length == 2) {return (int)(((data[p++] << 8) & 0xFF00L) | (data[p++] & 0xFFL));} else {return (int)(((data[p++] << 16) & 0xFF0000L) | ((data[p++] << 8) & 0xFF00L) | (data[p++] & 0xFFL));}}public byte[] toByteArray(String address) {if (address == null) {throw new IllegalArgumentException("Attempted to parse null address");}// 验证长度int first = 0, last = address.length();if (address.length() < 2) {throw new IllegalArgumentException(String.format("Invalid length - the string %s is too short to be an IPv6 address", address));}int length = last - first;if (length > 39) { // 32个数字 + 7个":"throw new IllegalArgumentException(String.format("Invalid length - the string %s is too long to be an IPv6 address. Length: %d",address, address.length()));}int partIndex = 0, partHexDigitCount = 0, afterDoubleSemicolonIndex = last + 2;// 获得缓存的字节数组byte[][] pool = cacheBytePool.get();if (pool == null) {initCacheBytePool();pool = cacheBytePool.get();}byte[] data = null;byte v;int k = 0, s = 0, x = 1, left = 0;for (int i = first; i < last; i++) {char c = address.charAt(i);if (isHexDigit(c)) {if (c == '0' && data == null) {continue;}// 定位当前段有几个数字, 且当前数字的序号：1 2 3 4 中的一个if (partHexDigitCount == 0) {int y = i + 1;until:{if (y >= last || address.charAt(y++) == ':') {break until;} else {x++;}if (y >= last || address.charAt(y++) == ':') {break until;} else {x++;}if (y >= last || address.charAt(y++) == ':') {break until;} else {x++;}}// ipv6分8段, 每一段都会写入两个字节left = left + 2;// 当前数字的序号partHexDigitCount = 4 - x;}// 初始化字节数组if (data == null) {int dataLength = ((7 - partIndex) << 1) + (x > 2 ? 2 : 1);data = pool[dataLength - 1];}// 每段数字不能超过4个if (++partHexDigitCount > 4) {throw new IllegalArgumentException(String.format("Ipv6 address %s parts must contain no more than 16 bits (4 hex digits)", address));}// 当前数字的字节值v = c >= 97 ? (byte)((c - 87) & 0xff) : (byte)((c - 48) & 0xff);// 0:0:12:c::12:226 将'c'的前一字节填充0if (x == 1 && partHexDigitCount == 4 && k > 0) {data[k] = 0;s++;k++;}// 0:0:12:2c::12:226 将'2c'的前一字节填充0if (x == 2 && partHexDigitCount == 3 && k > 0) {data[k] = 0;s++;k++;}// 根据数字位置填充字节的前一半if (partHexDigitCount == 1 || partHexDigitCount == 3) {data[k] = (byte)(v << 4);}// 填充字节的后一半if (partHexDigitCount == 2 || partHexDigitCount == 4) {// 如果此段只有一个数字,或者有3个数字，当前是第一个数字if (x == 1 || (partHexDigitCount == 2 && x == 3)) {data[k] = 0;}data[k] = (byte)(data[k] | v);s++;k++;}} else {if (c == ':') {if (data != null) {// 下一次写的字节位置if (k != 1) {k += 2 - s;}}s = 0;x = 1;partIndex++;partHexDigitCount = 0;// 如果存在连续的两个":", 即 "::"if (i < last - 1 && address.charAt(i + 1) == ':') {// 在两个: 之后的下一个数字的位置afterDoubleSemicolonIndex = i + 2;break;}continue;}throw new IllegalArgumentException(String.format("Ipv6 address %s illegal character: %c at index %d", address, c, i));}}// 从末尾倒叙向前遍历 直至 ::int lastFilledPartIndex = partIndex - 1, l = data.length - 1, right = l;partIndex = 7;for (int i = last - 1; i >= afterDoubleSemicolonIndex; i--) {char c = address.charAt(i);if (isHexDigit(c)) {if (partIndex <= lastFilledPartIndex) {throw new IllegalArgumentException(String.format("Ipv6 address %s too many parts. Expected 8 parts", address));}if (++partHexDigitCount > 4) {throw new IllegalArgumentException(String.format("Ipv6 address %s parts must contain no more than 16 bits (4 hex digits)", address));}// 当前数字的字节值v = c >= 97 ? (byte)((c - 87) & 0xff) : (byte)((c - 48) & 0xff);// 根据数字位置填充字节的后一半if (partHexDigitCount == 1 || partHexDigitCount == 3) {right--;data[l] = v;}// 填充字节的前一半if (partHexDigitCount == 2 || partHexDigitCount == 4) {data[l] = (byte)(data[l] | v << 4);s++;l--;}} else {if (c == ':') {l -= 2 - s;s = 0;partIndex--;partHexDigitCount = 0;continue;}throw new IllegalArgumentException(String.format("Ipv6 address %s illegal character: %c at index %d", address, c, i));}}// 填充 "::" 代表的空字节, 置为0, 因为字节数组是缓存重用的, 需要复位if (left != right) {for (int i = left; i <= right; i++) {data[i] = 0;}}return data;}private static boolean isHexDigit(char c) {return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f');}/*** 初始化ThreadLocal的二维字节数组*/private void initCacheBytePool() {//缓存待用字节数组byte[][] cacheBytes = new byte[16][];for (int i = 0; i < cacheBytes.length; i++) {cacheBytes[i] = new byte[i + 1];}cacheBytePool.set(cacheBytes);}/*** 比较两个字节数字的大小,逐位比较** @param array1 数组1* @param index1 开始的比较位* @param array2 数组2* @param index2 开始的比较位* @return int*/private int compareByteArray(byte[] array1, int index1, byte[] array2, int index2) {int k = 0, result = 0;for (int i = index1; i < index1 + array2.length; i++) {if (array1[i] != array2[index2 + k]) {return (array1[i] & 0xff) - (array2[index2 + k] & 0xff);}// end ip 和当前检索ip相同if (index2 + ++k == array2.length) {return 0;}}return result;}/*** 和起始ip比较** @param ip         检索ip* @param index* @param data       startIp后缀* @param startIndex* @return*/private boolean compareByStartIp(byte[] ip, int index, byte[] data, int startIndex) {int k = 0;for (int i = index; i < ip.length; i++) {int x1 = ip[i] & 0xff, x2 = data[startIndex + k] & 0xff;if (x1 < x2) {return false;} else if (x1 > x2) {return true;}k++;}return true;}}

工具类

工具类在V4版文章里，这里不重复贴了


http://www.ppmy.cn/devtools/149738.html

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