如何用java实现qqwry功能_云计算

发布时间:2024-10-01 14:33

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QQWry是一个中国大陆地区的IP数据库，用于将IP地址转换为地理位置信息。要实现QQWry功能，你需要下载QQWry的数据库文件，然后使用Java进行解析和查询。以下是一个简单的示例，说明如何使用Java实现QQWry功能：

首先，从官方网站（http://www.ipip.net/）下载QQWry的数据库文件（通常为.dat文件）。
将下载的.dat文件放入项目的资源文件夹中。
创建一个Java类，如QQWryUtil，并编写以下代码：

import java.io.*; import java.nio.ByteBuffer; import java.nio.channels.FileChannel; import java.util.zip.CRC32;  public class QQWryUtil {     private static final int MAX_IP_LENGTH = 15;     private static final int DATABASE_HEADER_SIZE = 7;     private static final int IP_ADDR_LENGTH = 4;     private static final int RECORD_LENGTH = 3;      private byte[] database;      public QQWryUtil(String filePath) throws IOException {         this.database = readDatabase(filePath);     }      private byte[] readDatabase(String filePath) throws IOException {         try (FileChannel fileChannel = new FileInputStream(filePath).getChannel()) {             long startOffset = DATABASE_HEADER_SIZE;             long fileSize = fileChannel.size();             byte[] buffer = new byte[RECORD_LENGTH];             int records = (int) ((fileSize - startOffset) / RECORD_LENGTH);              byte[] data = new byte[fileSize - DATABASE_HEADER_SIZE];             fileChannel.read(ByteBuffer.wrap(data), startOffset);              for (int i = 0; i < records; i++) {                 int recordStart = i * RECORD_LENGTH;                 int recordEnd = recordStart + RECORD_LENGTH;                 System.arraycopy(data, recordStart, buffer, 0, RECORD_LENGTH);                  int ipStart = getInt(buffer, 0);                 int ipEnd = getInt(buffer, 4);                 String ip = getIp(data, ipStart, ipEnd);                 int offset = getInt(buffer, 8);                  System.arraycopy(data, offset, data, recordStart, IP_ADDR_LENGTH);             }              return data;         }     }      private int getInt(byte[] buffer, int offset) {         return ((buffer[offset] & 0xFF) << 24) |                 ((buffer[offset + 1] & 0xFF) << 16) |                 ((buffer[offset + 2] & 0xFF) << 8) |                 (buffer[offset + 3] & 0xFF);     }      private String getIp(byte[] data, int start, int end) {         StringBuilder sb = new StringBuilder();         for (int i = start; i <= end; i += IP_ADDR_LENGTH) {             sb.append(String.format("%d.%d.%d.%d",                     getInt(data, i), getInt(data, i + 4), getInt(data, i + 8), getInt(data, i + 12)));             if (i != end) {                 sb.append(",");             }         }         return sb.toString();     }      public String getLocation(String ip) {         if (database == null) {             throw new IllegalStateException("Database not loaded.");         }          int index = search(ip);         if (index == -1) {             return "Unknown";         }          int offset = index * RECORD_LENGTH;         String country = new String(database, offset + 4, 2);         String region = new String(database, offset + 6, 2);         String city = new String(database, offset + 8, 2);         String isp = new String(database, offset + 10, 4);          return String.format("Country: %s, Region: %s, City: %s, ISP: %s", country, region, city, isp);     }      private int search(String ip) {         long startOffset = DATABASE_HEADER_SIZE;         long fileSize = database.length;         int left = 0;         int right = (int) (fileSize - DATABASE_HEADER_SIZE) - MAX_IP_LENGTH;          while (left <= right) {             int mid = left + (right - left) / 2;             int cmp = compareIp(database, startOffset + mid, ip);              if (cmp == 0) {                 return mid;             } else if (cmp < 0) {                 left = mid + 1;             } else {                 right = mid - 1;             }         }          return -1;     }      private int compareIp(byte[] data, int start, String ip) {         long ipValue = 0;         for (int i = 0; i < IP_ADDR_LENGTH; i++) {             ipValue = (ipValue << 8) | (data[start + i] & 0xFF);         }          long targetValue = 0;         for (int i = 0; i < IP_ADDR_LENGTH; i++) {             targetValue = (targetValue << 8) | (ip.charAt(i) - '0');         }          return (int) (ipValue - targetValue);     }      public static void main(String[] args) {         try {             QQWryUtil qqWryUtil = new QQWryUtil("path/to/your/qqwry.dat");             String ip = "8.8.8.8";             String location = qqWryUtil.getLocation(ip);             System.out.println("IP: " + ip + ", Location: " + location);         } catch (IOException e) {             e.printStackTrace();         }     } }