IPv6 supporting for Java searcher

binding/java/pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>org.lionsoul</groupId>
     <artifactId>ip2region</artifactId>
-    <version>2.8.1</version>
+    <version>3.1.0</version>
     <packaging>jar</packaging>
 
     <name>ip2region</name>
@@ -41,8 +41,8 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
-        <maven.compiler.source>1.6</maven.compiler.source>
+        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.6</maven.compiler.target>
+        <maven.compiler.target>1.8</maven.compiler.target>
     </properties>
 
     <dependencies>
@@ -105,7 +105,7 @@
                         <configuration>
                             <transformers>
                                 <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
-                                    <mainClass>org.lionsoul.ip2region.SearchTest</mainClass>
+                                    <mainClass>org.lionsoul.ip2region.SearchApp</mainClass>
                                 </transformer>
                             </transformers>
                         </configuration>

binding/java/src/main/java/org/lionsoul/ip2region/SearchApp.java

@@ -6,15 +6,18 @@
 
 package org.lionsoul.ip2region;
 
+import org.lionsoul.ip2region.xdb.InetAddressException;
+import org.lionsoul.ip2region.xdb.XdbException;
 import org.lionsoul.ip2region.xdb.LongByteArray;
 import org.lionsoul.ip2region.xdb.Searcher;
+import org.lionsoul.ip2region.xdb.Util;
+import org.lionsoul.ip2region.xdb.Version;
 
 import java.io.*;
 import java.nio.charset.Charset;
-import java.nio.charset.StandardCharsets;
 import java.util.concurrent.TimeUnit;
 
-public class SearchTest {
+public class SearchApp {
 
     public static void printHelp(String[] args) {
         System.out.print("ip2region xdb searcher\n");
@@ -24,21 +27,33 @@ public class SearchTest {
         System.out.print("  bench     search bench test\n");
     }
 
-    public static Searcher createSearcher(String dbPath, String cachePolicy) throws IOException {
+    public static Searcher createSearcher(String dbPath, String cachePolicy) throws IOException, XdbException {
+        final RandomAccessFile handle = new RandomAccessFile(dbPath, "r");
+
+        // verify the xdb file
+        // @Note: do NOT call it every time you create a searcher since this will slow
+        // down the search response.
+        // @see the util.Verify function for details.
+        Searcher.verify(handle);
+
+        // get the ip version from header
+        final Version version = Version.fromHeader(Searcher.loadHeader(handle));
+
+        // create the final searcher
         if ("file".equals(cachePolicy)) {
-            return Searcher.newWithFileOnly(dbPath);
+            return Searcher.newWithFileOnly(version, dbPath);
         } else if ("vectorIndex".equals(cachePolicy)) {
             byte[] vIndex = Searcher.loadVectorIndexFromFile(dbPath);
-            return Searcher.newWithVectorIndex(dbPath, vIndex);
+            return Searcher.newWithVectorIndex(version, dbPath, vIndex);
         } else if ("content".equals(cachePolicy)) {
             LongByteArray cBuff = Searcher.loadContentFromFile(dbPath);
-            return Searcher.newWithBuffer(cBuff);
+            return Searcher.newWithBuffer(version, cBuff);
         } else {
             throw new IOException("invalid cache policy `" + cachePolicy + "`, options: file/vectorIndex/content");
         }
     }
 
-    public static void searchTest(String[] args) throws IOException {
+    public static void searchTest(String[] args) throws IOException, XdbException {
         String dbPath = "", cachePolicy = "vectorIndex";
         for (final String r : args) {
             if (r.length() < 5) {
@@ -105,7 +120,7 @@ public class SearchTest {
         System.out.println("searcher test program exited, thanks for trying");
     }
 
-    public static void benchTest(String[] args) throws IOException {
+    public static void benchTest(String[] args) throws IOException, XdbException, InetAddressException {
         String dbPath = "", srcPath = "", cachePolicy = "vectorIndex";
         for (final String r : args) {
             if (r.length() < 5) {
@@ -155,40 +170,44 @@ public class SearchTest {
             String l = line.trim();
             String[] ps = l.split("\\|", 3);
             if (ps.length != 3) {
+                reader.close();
                 System.out.printf("invalid ip segment `%s`\n", l);
                 return;
             }
 
-            long sip;
+            byte[] sip;
             try {
-                sip = Searcher.checkIP(ps[0]);
+                sip = Util.parseIP(ps[0]);
             } catch (Exception e) {
+                reader.close();
                 System.out.printf("check start ip `%s`: %s\n", ps[0], e);
                 return;
             }
 
-            long eip;
+            byte[] eip;
             try {
-                eip = Searcher.checkIP(ps[1]);
+                eip = Util.parseIP(ps[1]);
             } catch (Exception e) {
+                reader.close();
                 System.out.printf("check end ip `%s`: %s\n", ps[1], e);
                 return;
             }
 
-            if (sip > eip) {
+            if (Util.ipCompare(sip, eip) > 0) {
+                reader.close();
                 System.out.printf("start ip(%s) should not be greater than end ip(%s)\n", ps[0], ps[1]);
                 return;
             }
 
-            long mip = (sip + eip) >> 1;
+            for (final byte[] ip : new byte[][]{sip, eip}) {
-            for (final long ip : new long[]{sip, (sip + mip) >> 1, mip, (mip + eip) >> 1, eip}) {
                 long sTime = System.nanoTime();
                 String region = searcher.search(ip);
                 costs += System.nanoTime() - sTime;
 
                 // check the region info
                 if (!ps[2].equals(region)) {
-                    System.out.printf("failed search(%s) with (%s != %s)\n", Searcher.long2ip(ip), region, ps[2]);
+                    System.out.printf("failed search(%s) with (%s != %s)\n", Util.ipToString(ip), region, ps[2]);
+                    reader.close();
                     return;
                 }
 
@@ -213,14 +232,14 @@ public class SearchTest {
         if ("search".equals(args[0])) {
             try {
                 searchTest(args);
-            } catch (IOException e) {
+            } catch (Exception e) {
                 System.out.printf("failed running search test: %s\n", e);
             }
         } else if ("bench".equals(args[0])) {
             try {
                 benchTest(args);
-            } catch (IOException e) {
+            } catch (Exception e) {
-                System.out.printf("failed running bench test: %s\n", e);
+                System.out.printf("fwailed running bench test: %s\n", e);
             }
         } else {
             printHelp(args);

binding/java/src/main/java/org/lionsoul/ip2region/UtilTest.java

@@ -1,85 +0,0 @@
-// Copyright 2022 The Ip2Region Authors. All rights reserved.
-// Use of this source code is governed by a Apache2.0-style
-// license that can be found in the LICENSE file.
-// @Author Lion <chenxin619315@gmail.com>
-// @Date   2022/06/23
-
-package org.lionsoul.ip2region;
-
-import org.lionsoul.ip2region.xdb.LongByteArray;
-import org.lionsoul.ip2region.xdb.Searcher;
-
-import java.util.Arrays;
-
-public class UtilTest {
-
-    public static void testIP2Long() {
-        String ip = "1.2.3.4";
-        long ipAddr = 0;
-        try {
-            ipAddr = Searcher.checkIP(ip);
-        } catch (Exception e) {
-            System.out.printf("failed to check ip: %s\n", e);
-            return;
-        }
-
-        if (ipAddr != 16909060) {
-            System.out.print("failed ip2long\n");
-            return;
-        }
-
-        String ip2 = Searcher.long2ip(ipAddr);
-        if (!ip.equals(ip2)) {
-            System.out.print("failed long2ip\n");
-            return;
-        }
-
-        System.out.printf("passed: ip=%s, ipAddr=%d, ip2=%s\n", ip, ipAddr, ip2);
-    }
-
-    public static void testLongByteArray() {
-        final LongByteArray byteArray = new LongByteArray();
-        byteArray.append(new byte[]{0,0,0,0,0});
-        byteArray.append(new byte[]{1,1,1,1,1});
-        int counter = 2;
-        for (int i = 0; i < 100; i++) {
-            final byte[] buff = new byte[10];
-            Arrays.fill(buff, (byte) counter);
-            byteArray.append(buff);
-            counter++;
-        }
-
-        System.out.printf("1, byteArray.length: %d\n", byteArray.length());
-        System.out.println("2, length copy test...");
-        int[] length = new int[]{5, 10, 15, 20, 21, 22, 23, 25, 28, 29, 30, 40, 42, 44, 50, 60};
-        for (int j : length) {
-            final byte[] destBuff = new byte[j];
-            byteArray.copy(0, destBuff, 0, destBuff.length);
-            System.out.printf("copy(0,%d): \n", destBuff.length);
-            for (byte b : destBuff) {
-                System.out.print(b + " ");
-            }
-            System.out.println();
-        }
-
-        System.out.println("3, offset copy test...");
-        int[] offset = new int[]{0, 5, 10, 15, 20, 21, 22, 23, 25, 28, 29, 30, 40, 42, 44, 50, 60};
-        for (int j : offset) {
-            final byte[] destBuff = new byte[11];
-            byteArray.copy(j, destBuff, 0, destBuff.length);
-            System.out.printf("copy(%d,%d): \n", j, destBuff.length);
-            for (byte b : destBuff) {
-                System.out.print(b + " ");
-            }
-            System.out.println();
-        }
-    }
-
-    public static void main(String[] args) {
-        System.out.print("testing IP2Long ... \n");
-        testIP2Long();
-        System.out.print("testing LongByteArray ... \n");
-        testLongByteArray();
-    }
-
-}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/Header.java

@@ -9,18 +9,25 @@ package org.lionsoul.ip2region.xdb;
 public class Header {
     public final int version;
     public final int indexPolicy;
-    public final int createdAt;
+    public final long createdAt;
-    public final int startIndexPtr;
+    public final long startIndexPtr;
-    public final int endIndexPtr;
+    public final long endIndexPtr;
+
+    // since xdb 3.0 with IPv6 supporting
+    public final int ipVersion;
+    public final int runtimePtrBytes;
+
     public final byte[] buffer;
 
     public Header(byte[] buff) {
         assert buff.length >= 16;
-        version = Searcher.getInt2(buff, 0);
+        version = LittleEndian.getInt2(buff, 0);
-        indexPolicy = Searcher.getInt2(buff, 2);
+        indexPolicy = LittleEndian.getInt2(buff, 2);
-        createdAt = Searcher.getInt(buff, 4);
+        createdAt = LittleEndian.getUint32(buff, 4);
-        startIndexPtr = Searcher.getInt(buff, 8);
+        startIndexPtr = LittleEndian.getUint32(buff, 8);
-        endIndexPtr = Searcher.getInt(buff, 12);
+        endIndexPtr = LittleEndian.getUint32(buff, 12);
+        ipVersion = LittleEndian.getInt2(buff, 16);
+        runtimePtrBytes = LittleEndian.getInt2(buff, 18);
         buffer = buff;
     }
 
@@ -30,7 +37,9 @@ public class Header {
             "IndexPolicy: " + indexPolicy + ',' +
             "CreatedAt: " + createdAt + ',' +
             "StartIndexPtr: " + startIndexPtr + ',' +
-            "EndIndexPtr: " + endIndexPtr +
+            "EndIndexPtr: " + endIndexPtr + ',' + 
+            "IPVersion: " + ipVersion + ',' + 
+            "RuntimePtrBytes: " + runtimePtrBytes +
         '}';
     }
 }

binding/java/src/main/java/org/lionsoul/ip2region/xdb/IPv4.java

@@ -0,0 +1,47 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+
+package org.lionsoul.ip2region.xdb;
+
+// IPv4 version implementation
+// @Author Lion <chenxin619315@gmail.com>
+// @Date   2025/09/10
+
+public class IPv4 extends Version {
+    public IPv4() {
+        // segmentIndex: 4 + 4 + 2 + 4
+        super(4, "IPv4", 4, 14);
+    }
+
+    @Override
+    public int putBytes(byte[] buff, int offset, byte[] ip) {
+        // use the Little endian byte order to compatible with the old searcher implementation
+        buff[offset++] = ip[3];
+        buff[offset++] = ip[2];
+        buff[offset++] = ip[1];
+        buff[offset  ] = ip[0];
+        return ip.length;
+    }
+
+    @Override
+    public int ipSubCompare(byte[] ip1, byte[] buff, int offset) {
+        // ip1: Big endian byte order parsed from input
+        // ip2: Little endian byte order read from xdb index.
+        // @Note: to compatible with the old Litten endian index encode implementation.
+        int j = offset + ip1.length - 1;
+        for (int i = 0; i < ip1.length; i++, j--) {
+            final int i1 = (int) (ip1[i] & 0xFF);
+            final int i2 = (int) (buff[j] & 0xFF);
+            if (i1 < i2) {
+                return -1;
+            }
+
+            if (i1 > i2) {
+                return 1;
+            }
+        }
+
+        return 0;
+    }
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/IPv6.java

@@ -0,0 +1,29 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+
+package org.lionsoul.ip2region.xdb;
+
+// IPv4 version implementation
+// @Author Lion <chenxin619315@gmail.com>
+// @Date   2025/09/10
+
+public class IPv6 extends Version {
+
+    public IPv6() {
+        // segmentIndex: 16 + 16 + 2 + 4
+        super(6, "IPv6", 16, 38);
+    }
+
+    @Override
+    public int putBytes(byte[] buff, int offset, byte[] ip) {
+        System.arraycopy(ip, 0, buff, offset, ip.length);
+        return ip.length;
+    }
+
+    @Override
+    public int ipSubCompare(byte[] ip1, byte[] buff, int offset) {
+        return Util.ipSubCompare(ip1, buff, offset);
+    }
+
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/InetAddressException.java

@@ -0,0 +1,13 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+
+package org.lionsoul.ip2region.xdb;
+
+public class InetAddressException extends Exception {
+
+    public InetAddressException(String str) {
+        super(str);
+    }
+
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/LittleEndian.java

@@ -0,0 +1,58 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+
+package org.lionsoul.ip2region.xdb;
+
+// Little Endian basic data type decode and encode.
+// @Author Lion <chenxin619315@gmail.com>
+// @Date   2025/09/10
+
+public class LittleEndian {
+
+    public final static int[] shiftIndex = {0, 8, 16, 24, 32, 40, 48, 56};
+    
+    // put specified bytes to the buffer started from the offset
+    public static void put(final byte[] buff, int offset, long value, int bytes) {
+        if (bytes > 8) {
+            throw new IndexOutOfBoundsException("bytes should be <= 8");
+        }
+
+        for (int i = 0; i < bytes; i++) {
+            buff[offset++] = (byte)((value >>> shiftIndex[i]) & 0xFF);
+        }
+    }
+
+    // put an uint32 (4 bytes long) to the buffer from the offset
+    public static void putUint32(final byte[] buff, int offset, long value) {
+        buff[offset++] = (byte) (value & 0xFF);
+        buff[offset++] = (byte) ((value >>  8) & 0xFF);
+        buff[offset++] = (byte) ((value >> 16) & 0xFF);
+        buff[offset  ] = (byte) ((value >> 24) & 0xFF);
+    }
+
+    // put a 2-bytes int to the buffer from the specified offset
+    public static void putInt2(final byte[] buff, int offset, int value) {
+        buff[offset++] = (byte) (value & 0xFF);
+        buff[offset  ] = (byte) ((value >>  8) & 0xFF);
+    }
+
+    // get an uint32 from a byte array from the specified offset
+    public static long getUint32(final byte[] buff, int offset) {
+        return (
+            ((buff[offset++] & 0x000000FFL)) |
+            ((buff[offset++] <<  8) & 0x0000FF00L) |
+            ((buff[offset++] << 16) & 0x00FF0000L) |
+            ((buff[offset  ] << 24) & 0xFF000000L)
+        );
+    }
+
+    // get an 2 bytes int from a byte array from the specified offset
+    public static int getInt2(final byte[] buff, int offset) {
+        return (
+            ((buff[offset++]) & 0x000000FF) |
+            ((buff[offset  ] << 8) & 0x0000FF00)
+        );
+    }
+
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/Log.java

@@ -0,0 +1,119 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+//
+// @Author Lion <chenxin619315@gmail.com>
+// @Date   2022/07/14
+
+package org.lionsoul.ip2region.xdb;
+
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+// simple log implementation
+public class Log {
+
+    /* Log level constants define */
+    public static final int DEBUG = 0;
+    public static final int INFO = 1;
+    public static final int WARN = 2;
+    public static final int ERROR = 3;
+
+    // level name
+    public static final String[] level_string = new String[] {
+        "DEBUG",
+        "INFO",
+        "WARN",
+        "ERROR"
+    };
+
+    public final Class<?> baseClass;
+    private int level = INFO;
+
+    public Log(Class<?> baseClass) {
+        this.baseClass = baseClass;
+    }
+
+    public static Log getLogger(Class<?> baseClass) {
+        return new Log(baseClass);
+    }
+
+    public String format(int level, String format, Object... args) {
+        // append the datetime
+        final StringBuilder sb = new StringBuilder();
+        final SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
+        sb.append(String.format("%s %-5s ", sdf.format(new Date()), level_string[level]));
+
+        // append the class name
+        sb.append(baseClass.getName()).append(' ');
+        sb.append(String.format(format, args));
+        return sb.toString();
+    }
+
+    public void printf(int level, String format, Object... args) {
+        if (level < DEBUG || level > ERROR) {
+            throw new IndexOutOfBoundsException("invalid level index " + level);
+        }
+
+        // level filter
+        if (level < this.level) {
+            return;
+        }
+
+        System.out.println(format(level, format, args));
+        System.out.flush();
+    }
+
+    public String getDebugf(String format, Object... args) {
+        return format(DEBUG, format, args);
+    }
+
+    public void debugf(String format, Object... args) {
+        printf(DEBUG, format, args);
+    }
+
+    public String getInfof(String format, Object... args) {
+        return format(INFO, format, args);
+    }
+
+    public void infof(String format, Object... args) {
+        printf(INFO, format, args);
+    }
+
+    public String getWarnf(String format, Object... args) {
+        return format(WARN, format, args);
+    }
+
+    public void warnf(String format, Object... args) {
+        printf(WARN, format, args);
+    }
+
+    public String getErrorf(String format, Object... args) {
+        return format(ERROR, format, args);
+    }
+
+    public void errorf(String format, Object... args) {
+        printf(ERROR, format, args);
+    }
+
+    public Log setLevel(int level) {
+        this.level = level;
+        return this;
+    }
+
+    public Log setLevel(String level) {
+        String v = level.toLowerCase();
+        if ("debug".equals(v)) {
+            this.level = DEBUG;
+        } else if ("info".equals(v)) {
+            this.level = INFO;
+        } else if ("warn".equals(v)) {
+            this.level = WARN;
+        } else if ("error".equals(v)) {
+            this.level = ERROR;
+        }
+
+        return this;
+    }
+
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/LongByteArray.java

@@ -104,27 +104,17 @@ public class LongByteArray {
         return copy(offset, buffer, 0, length);
     }
 
-    // get a 4-bytes long integer from the specified index
+    // get a 4-bytes uint32 integer from the specified index
-    public long getIntLong(long offset) {
+    public long getUint32(long offset) {
         final byte[] b = new byte[4];
         copy(offset, b, 0, 4);
-        return (
+        return LittleEndian.getUint32(b, 0);
-            ((b[0] & 0x000000FFL)) |
-            ((b[1] <<  8) & 0x0000FF00L) |
-            ((b[2] << 16) & 0x00FF0000L) |
-            ((b[3] << 24) & 0xFF000000L)
-        );
     }
 
-    public int getInt(long offset) {
+    public int getInt2(long offset) {
         final byte[] b = new byte[4];
         copy(offset, b, 0, 4);
-        return (
+        return LittleEndian.getInt2(b, 0);
-            ((b[0] & 0x000000FF)) |
-            ((b[1] <<  8) & 0x0000FF00) |
-            ((b[2] << 16) & 0x00FF0000) |
-            ((b[3] << 24) & 0xFF000000)
-        );
     }
 
     // position entry class

binding/java/src/main/java/org/lionsoul/ip2region/xdb/Searcher.java

@@ -8,21 +8,26 @@ package org.lionsoul.ip2region.xdb;
 // @Author Lion <chenxin619315@gmail.com>
 // @Date   2022/06/23
 
-
 import java.io.IOException;
 import java.io.RandomAccessFile;
 
 public class Searcher {
+    // xdb structure version no
+    public static final int STRUCTURE_20 = 2;
+    public static final int STRUCTURE_30 = 3;
+
     // constant defined copied from the xdb maker
     public static final int HeaderInfoLength = 256;
     public static final int VectorIndexRows  = 256;
     public static final int VectorIndexCols  = 256;
     public static final int VectorIndexSize  = 8;
-    public static final int SegmentIndexSize = 14;
 
     // Linux max write / read bytes
     public static final int MAX_WRITE_BYTES = 0x7ffff000;
 
+    // ip version
+    private final Version version;
+
     // random access file handle for file-based search
     private final RandomAccessFile handle;
 
@@ -40,21 +45,22 @@ public class Searcher {
 
     // --- static method to create searchers
 
-    public static Searcher newWithFileOnly(String dbPath) throws IOException {
+    public static Searcher newWithFileOnly(Version version, String dbPath) throws IOException {
-        return new Searcher(dbPath, null, null);
+        return new Searcher(version, dbPath, null, null);
     }
 
-    public static Searcher newWithVectorIndex(String dbPath, byte[] vectorIndex) throws IOException {
+    public static Searcher newWithVectorIndex(Version version, String dbPath, byte[] vectorIndex) throws IOException {
-        return new Searcher(dbPath, vectorIndex, null);
+        return new Searcher(version, dbPath, vectorIndex, null);
     }
 
-    public static Searcher newWithBuffer(LongByteArray cBuff) throws IOException {
+    public static Searcher newWithBuffer(Version version, LongByteArray cBuff) throws IOException {
-        return new Searcher(null, null, cBuff);
+        return new Searcher(version, null, null, cBuff);
     }
 
     // --- End of creator
 
-    public Searcher(String dbFile, byte[] vectorIndex, LongByteArray cBuff) throws IOException {
+    public Searcher(Version version, String dbFile, byte[] vectorIndex, LongByteArray cBuff) throws IOException {
+        this.version = version;
         if (cBuff != null) {
             this.handle = null;
             this.vectorIndex = null;
@@ -72,62 +78,68 @@ public class Searcher {
         }
     }
 
+    public Version getIPVersion() {
+        return version;
+    }
+
     public int getIOCount() {
         return ioCount;
     }
 
     public String search(String ipStr) throws Exception {
-        long ip = checkIP(ipStr);
+        return search(Util.parseIP(ipStr));
-        return search(ip);
     }
 
-    public String search(long ip) throws IOException {
+    public String search(byte[] ip) throws IOException, InetAddressException {
+        // ip version check
+        if (ip.length != version.bytes) {
+            throw new InetAddressException("invalid ip address ("+version.name+" expected)");
+        }
+
         // reset the global counter
         this.ioCount = 0;
 
         // locate the segment index block based on the vector index
         long sPtr = 0, ePtr = 0;
-        int il0 = (int) ((ip >> 24) & 0xFF);
+        int il0 = (int) (ip[0] & 0xFF);
-        int il1 = (int) ((ip >> 16) & 0xFF);
+        int il1 = (int) (ip[1] & 0xFF);
         int idx = il0 * VectorIndexCols * VectorIndexSize + il1 * VectorIndexSize;
         // System.out.printf("il0: %d, il1: %d, idx: %d\n", il0, il1, idx);
         if (vectorIndex != null) {
-            sPtr = getIntLong(vectorIndex, idx);
+            sPtr = LittleEndian.getUint32(vectorIndex, idx);
-            ePtr = getIntLong(vectorIndex, idx + 4);
+            ePtr = LittleEndian.getUint32(vectorIndex, idx + 4);
         } else if (contentBuff != null) {
-            sPtr = contentBuff.getIntLong(HeaderInfoLength + idx);
+            sPtr = contentBuff.getUint32(HeaderInfoLength + idx);
-            ePtr = contentBuff.getIntLong(HeaderInfoLength + idx + 4);
+            ePtr = contentBuff.getUint32(HeaderInfoLength + idx + 4);
         } else {
             final byte[] buff = new byte[VectorIndexSize];
             read(HeaderInfoLength + idx, buff);
-            sPtr = getIntLong(buff, 0);
+            sPtr = LittleEndian.getUint32(buff, 0);
-            ePtr = getIntLong(buff, 4);
+            ePtr = LittleEndian.getUint32(buff, 4);
         }
 
         // System.out.printf("sPtr: %d, ePtr: %d\n", sPtr, ePtr);
 
         // binary search the segment index block to get the region info
-        final byte[] buff = new byte[SegmentIndexSize];
+        final int bytes = ip.length, dBytes = ip.length << 1;
+        final int segIndexSize = version.segmentIndexSize;
+        final byte[] buff = new byte[segIndexSize];
         int dataLen = -1;
-        long dataPtr = -1, l = 0, h = (ePtr - sPtr) / SegmentIndexSize;
+        long dataPtr = -1, l = 0, h = (ePtr - sPtr) / segIndexSize;
         while (l <= h) {
             long m = (l + h) >> 1;
-            long p = sPtr + m * SegmentIndexSize;
+            long p = sPtr + m * segIndexSize;
 
             // read the segment index
             read(p, buff);
-            long sip = getIntLong(buff, 0);
+            if (version.ipSubCompare(ip, buff, 0) < 0) {
-            if (ip < sip) {
                 h = m - 1;
+            } else if (version.ipSubCompare(ip, buff, bytes) > 0) {
+                l = m + 1;
             } else {
-                long eip = getIntLong(buff, 4);
+                dataLen = LittleEndian.getInt2(buff, dBytes);
-                if (ip > eip) {
+                dataPtr = LittleEndian.getUint32(buff, dBytes + 2);
-                    l = m + 1;
+                break;
-                } else {
-                    dataLen = getInt2(buff, 8);
-                    dataPtr = getIntLong(buff, 10);
-                    break;
-                }
             }
         }
 
@@ -161,7 +173,7 @@ public class Searcher {
         }
     }
 
-    // --- static cache util function
+    // --- static util function
 
     public static Header loadHeader(RandomAccessFile handle) throws IOException {
         handle.seek(0);
@@ -222,63 +234,39 @@ public class Searcher {
         return content;
     }
 
-    // --- End cache load util function
+    // --- verify util function
 
-    // --- static util method
+    // Verify if the current Searcher could be used to search the specified xdb file.
+    // Why do we need this check ?
+    // The future features of the xdb impl may cause the current searcher not able to work properly.
+    //
+    // @Note: You Just need to check this ONCE when the service starts
+    // Or use another process (eg, A command) to check once Just to confirm the suitability.
+    public static void verify(RandomAccessFile handle) throws IOException, XdbException {
+        final Header header = loadHeader(handle);
 
-    /* get an int from a byte array start from the specified offset */
+        // get the runtime ptr bytes
-    public static long getIntLong(byte[] b, int offset) {
+        int runtimePtrBytes = 0;
-        return (
+        if (header.version == STRUCTURE_20) {
-            ((b[offset++] & 0x000000FFL)) |
+            runtimePtrBytes = 4;
-            ((b[offset++] <<  8) & 0x0000FF00L) |
+        } else if (header.version == STRUCTURE_30) {
-            ((b[offset++] << 16) & 0x00FF0000L) |
+            runtimePtrBytes = header.runtimePtrBytes;
-            ((b[offset  ] << 24) & 0xFF000000L)
+        } else {
-        );
+            throw new XdbException("invalid structure version `" + header.version + "`");
-    }
-
-    public static int getInt(byte[] b, int offset) {
-        return (
-            ((b[offset++] & 0x000000FF)) |
-            ((b[offset++] <<  8) & 0x0000FF00) |
-            ((b[offset++] << 16) & 0x00FF0000) |
-            ((b[offset  ] << 24) & 0xFF000000)
-        );
-    }
-
-    public static int getInt2(byte[] b, int offset) {
-        return (
-            ((b[offset++] & 0x000000FF)) |
-            ((b[offset  ] << 8) & 0x0000FF00)
-        );
-    }
-
-    /* long int to ip string */
-    public static String long2ip( long ip )
-    {
-        return String.valueOf((ip >> 24) & 0xFF) + '.' +
-            ((ip >> 16) & 0xFF) + '.' + ((ip >> 8) & 0xFF) + '.' + ((ip) & 0xFF);
-    }
-
-    public static final byte[] shiftIndex = {24, 16, 8, 0};
-
-    /* check the specified ip address */
-    public static long checkIP(String ip) throws Exception {
-        String[] ps = ip.split("\\.");
-        if (ps.length != 4) {
-            throw new Exception("invalid ip address `" + ip + "`");
         }
 
-        long ipDst = 0;
+        // 1, confirm the xdb file size
-        for (int i = 0; i < ps.length; i++) {
+        // to ensure that the maximum file pointer does not overflow
-            int val = Integer.parseInt(ps[i]);
+        final long maxFilePtr = (1L << (runtimePtrBytes * 8)) - 1;
-            if (val > 255) {
+        if (handle.length() > maxFilePtr) {
-                throw new Exception("ip part `"+ps[i]+"` should be less then 256");
+            throw new XdbException("xdb file exceeds the maximum supported bytes: "+maxFilePtr+"");
-            }
-
-            ipDst |= ((long) val << shiftIndex[i]);
         }
+    }
 
-        return ipDst & 0xFFFFFFFFL;
+    public static void verifyFromFile(String dbFile) throws IOException, XdbException {
+        final RandomAccessFile handle = new RandomAccessFile(dbFile, "r");
+        verify(handle);
+        handle.close();
     }
 
 }

binding/java/src/main/java/org/lionsoul/ip2region/xdb/Util.java

@@ -0,0 +1,78 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+//
+// @Author Lion <chenxin619315@gmail.com>
+// @Date   2022/07/14
+
+package org.lionsoul.ip2region.xdb;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+public class Util
+{
+
+    // parse the specified IP address and return its bytes.
+    // returns: byte[4] for IPv4 and byte[16] for IPv6 and the bytes should be in Big endian order.
+    public static byte[] parseIP(String ip) throws InetAddressException {
+        try {
+            return InetAddress.getByName(ip).getAddress();
+        } catch (UnknownHostException e) {
+            throw new InetAddressException("invalid ip address `"+ip+"`");
+        }
+    }
+
+    // convert the byte[] ip to string ip address
+    public static String ipToString(final byte[] ip) {
+        if (ip.length != 4 && ip.length != 16) {
+            return String.format("invalid-ip-address-length: %d", ip.length);
+        }
+
+        try {
+            return InetAddress.getByAddress(ip).getHostAddress();
+        } catch (UnknownHostException e) {
+            return String.format("invalid-ip-address `%s`", ipArrayString(ip));
+        }
+    }
+
+    // implode the byte[] ip with its byte value.
+    public static String ipArrayString(byte[] ip) {
+        final StringBuffer sb = new StringBuffer();
+        sb.append("[");
+        for (int i = 0; i < ip.length; i++) {
+            if (i > 0) {
+                sb.append(',');
+            }
+            sb.append((ip[i] & 0xFF));
+        }
+        sb.append("]");
+        return sb.toString();
+    }
+
+    // compare two byte ip
+    // Returns: -1 if ip1 < ip2, 0 if ip1 == ip2, 1 if ip1 > ip2
+    public static int ipCompare(byte[] ip1, byte[] ip2) {
+        return ipSubCompare(ip1, ip2, 0);
+    }
+
+    // compare the ip with the ip in the buffer start from offset
+    // Returns: -1 if ip < buff[offset], 0 if ip == buff[offset], 1 if ip > buff[offset]
+    public static int ipSubCompare(byte[] ip, byte[] buff, int offset) {
+        for (int i = 0; i < ip.length; i++) {
+            // covert the byte to int to sure the uint8 attribute
+            final int i1 = (int)(ip[i] & 0xFF);
+            final int i2 = (int)(buff[offset+i] & 0xFF);
+            if (i1 < i2) {
+                return -1;
+            }
+
+            if (i1 > i2) {
+                return 1;
+            }
+        }
+
+        return 0;
+    }
+
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/Version.java

@@ -0,0 +1,83 @@
+// Copyright 2025 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+
+package org.lionsoul.ip2region.xdb;
+
+// IP version abstract manager (IPv4 & IPv6)
+// @Author Lion <chenxin619315@gmail.com>
+// @Date   2025/09/10
+
+public abstract class Version {
+    public static final int IPv4VersionNo = 4;
+    public static final int IPv6VersionNo = 6;
+
+    public static final IPv4 IPv4 = new IPv4();
+    public static final IPv6 IPv6 = new IPv6();
+
+    // version id and name
+    public final int id;
+    public final String name;
+    
+    // the numbers of bytes for one IP
+    public final int bytes;
+
+    // segment index size (bytes)
+    public final int segmentIndexSize;
+
+    public Version(int id, String name, int bytes, int segmentIndexSize) {
+        this.id = id;
+        this.name = name;
+        this.bytes = bytes;
+        this.segmentIndexSize = segmentIndexSize;
+    }
+
+    // encode the specified IP bytes to the specified buffer
+    public abstract int putBytes(byte[] buff, int offset, byte[] ip);
+
+    // compare the two IPs with the current version.
+    // Returns: -1 if ip1 < ip2, 0 if ip1 == ip2, 1 if ip1 > ip2
+    public int ipCompare(byte[] ip1, byte[] ip2) {
+        return ipSubCompare(ip1, ip2, 0);
+    }
+
+    // @see ipCompare
+    public abstract int ipSubCompare(byte[] ip1, byte[] buff, int offset);
+
+    // parse the version from an name
+    public static final Version fromName(String name) throws Exception {
+        final String n = name.toUpperCase();
+        if (n.equals("V4") || n.equals("IPV4")) {
+            return IPv4;
+        } else if (n.equals("V6") || n.equals("IPV6")) {
+            return IPv6;
+        } else {
+            throw new Exception("invalid version name `"+name+"`");
+        }
+    }
+
+    // parse the version from header
+    public static final Version fromHeader(Header header) throws XdbException {
+        // Old 2.0 structure with IPv4 supports ONLY.
+        if (header.version == Searcher.STRUCTURE_20) {
+            return IPv4;
+        }
+
+        // structure 3.0 after IPv6 supporting
+        if (header.version != Searcher.STRUCTURE_30) {
+            throw new XdbException("invalid xdb structure version `"+header.version+"`");
+        }
+
+        if (header.ipVersion == IPv4VersionNo) {
+            return IPv4;
+        } else if (header.ipVersion == IPv6VersionNo) {
+            return IPv6;
+        } else {
+            throw new XdbException("invalid ip version number `" + header.ipVersion + "`");
+        }
+    }
+
+    @Override public String toString() {
+        return String.format("{Id:%d, Name:%s, Bytes:%d, IndexSize: %d}", id, name, bytes, segmentIndexSize);
+    }
+}

binding/java/src/main/java/org/lionsoul/ip2region/xdb/XdbException.java

@@ -0,0 +1,13 @@
+// Copyright 2022 The Ip2Region Authors. All rights reserved.
+// Use of this source code is governed by a Apache2.0-style
+// license that can be found in the LICENSE file.
+
+package org.lionsoul.ip2region.xdb;
+
+public class XdbException extends Exception {
+
+    public XdbException(String str) {
+        super(str);
+    }
+
+}

binding/java/src/main/java/xdb/Version.java

@@ -0,0 +1,5 @@
+package xdb;
+
+public class Version {
+
+}

binding/java/src/test/java/org/lionsoul/ip2region/xdb/LittleEndianTest.java

@@ -0,0 +1,36 @@
+package org.lionsoul.ip2region.xdb;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class LittleEndianTest {
+
+    private static final Log log = Log.getLogger(LittleEndianTest.class).setLevel(Log.DEBUG);
+
+    @Test
+    public void testAll() {
+        final byte[] buff = new byte[14];
+
+        // encode
+        // do the put
+        LittleEndian.put(buff, 0, 1L, 4);
+        LittleEndian.put(buff, 4, 2L, 4);
+
+        // putUint32
+        LittleEndian.putInt2(buff, 8, 24);
+        LittleEndian.putUint32(buff, 10, 1024L);
+
+        // decode
+        assertEquals(LittleEndian.getUint32(buff, 0), 1);
+        assertEquals(LittleEndian.getUint32(buff, 4), 2);
+        assertEquals(LittleEndian.getInt2(buff, 8), 24);
+        assertEquals(LittleEndian.getUint32(buff, 10), 1024);
+
+        log.debugf("uint32(buff, 0): %d", LittleEndian.getUint32(buff, 0));
+        log.debugf("uint32(buff, 4): %d", LittleEndian.getUint32(buff, 4));
+        log.debugf("int2(buff, 8): %d", LittleEndian.getInt2(buff, 8));
+        log.debugf("uint32(buff, 10): %d", LittleEndian.getUint32(buff, 10));
+    }
+
+}

binding/java/src/test/java/org/lionsoul/ip2region/xdb/UtilTest.java

@@ -0,0 +1,45 @@
+package org.lionsoul.ip2region.xdb;
+
+import org.junit.Test;
+
+public class UtilTest {
+
+    private static final Log log = Log.getLogger(UtilTest.class).setLevel(Log.DEBUG);
+
+    @Test
+    public void testCheckIP() throws InetAddressException {
+        final String[] ips = new String[]{
+            "192.168.1.102",
+            "219.133.111.87",
+            "::",
+            "3000::",
+            "::1001:ffff",
+            "2001:2:0:ffff:ffff:ffff:ffff:ffff",
+            "::ffff:114.114.114.114"
+        };
+
+        for (String ip : ips) {
+            final byte[] ipBytes = Util.parseIP(ip);
+            log.debugf("%s(v=%s) => %s", ip, Util.ipArrayString(ipBytes), Util.ipToString(ipBytes));
+        }
+    }
+
+    @Test
+    public void testIpCompare() throws InetAddressException {
+        final String[][] ipPairs = new String[][]{
+            {"1.0.0.0", "1.0.0.1"},
+            {"192.168.1.101", "192.168.1.90"},
+            {"219.133.111.87", "114.114.114.114"},
+            {"2000::", "2000:ffff:ffff:ffff:ffff:ffff:ffff:ffff"},
+            {"2001:4:112::", "2001:4:112:ffff:ffff:ffff:ffff:ffff"},
+            {"ffff::", "2001:4:ffff:ffff:ffff:ffff:ffff:ffff"}
+        };
+
+        for (String[] ips : ipPairs) {
+            final byte[] ip1 = Util.parseIP(ips[0]);
+            final byte[] ip2 = Util.parseIP(ips[1]);
+            log.debugf("compare(%s, %s): %d", ips[0], ips[1], Util.ipCompare(ip1, ip2));
+        }
+    }
+
+}

binding/java/src/test/java/org/lionsoul/ip2region/xdb/VersionTest.java

@@ -0,0 +1,22 @@
+package org.lionsoul.ip2region.xdb;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class VersionTest {
+
+    private static final Log log = Log.getLogger(VersionTest.class).setLevel(Log.DEBUG);
+
+    @Test
+    public void testFromName() throws Exception {
+        final String[] vers = new String[]{"IPv4", "IPv6"};
+        final Version v4 = Version.fromName(vers[0]);
+        assertEquals(v4.name, vers[0]);
+        final Version v6 = Version.fromName(vers[1]);
+        assertEquals(v6.name, vers[1]);
+
+        log.debugf("v4: %s", v4);
+        log.debugf("v6: %s", v6);
+    }
+}