diff --git a/binding/java/src/test/java/org/lionsoul/ip2region/xdb/BufferTest.java b/binding/java/src/test/java/org/lionsoul/ip2region/xdb/BufferTest.java
index 59fa6b4..541ddd1 100644
--- a/binding/java/src/test/java/org/lionsoul/ip2region/xdb/BufferTest.java
+++ b/binding/java/src/test/java/org/lionsoul/ip2region/xdb/BufferTest.java
@@ -1,6 +1,8 @@
 package org.lionsoul.ip2region.xdb;
 
+import java.io.File;
 import java.io.FileInputStream;
+import java.io.IOException;
 import java.security.CodeSource;
 
 import org.junit.Test;
@@ -19,6 +21,8 @@ public class BufferTest {
         }
     }
 
+    // --- v4
+
     @Test
     public void testV4InputStreamBuffer() throws Exception {
         final LongByteArray cBuffer = Searcher.loadContentFromInputStream(
@@ -27,6 +31,48 @@ public class BufferTest {
         log.debugf("cBuffer->{length:%d, size:%d}", cBuffer.length(), cBuffer.size());
     }
 
+    @Test
+    public void testV4FixedBuffer() throws Exception {
+        final LongByteArray cBuffer = Searcher.loadContentFromFile(
+            new File(getDataPath("ip2region_v4.xdb")), 2 * 1024 * 1024
+        );
+        final Header header = Searcher.loadHeaderFromBuffer(cBuffer);
+        log.debugf("cBuffer->{length:%d, size:%d}", cBuffer.length(), cBuffer.size());
+        log.debugf("Header->%s", header);
+    }
+
+    @Test
+    public void testV4BufferAssert() throws Exception {
+        final LongByteArray m2Bufer = Searcher.loadContentFromFile(
+            new File(getDataPath("ip2region_v4.xdb")), 2 * 1024 * 1024
+        );
+        final LongByteArray m5Bufer = Searcher.loadContentFromFile(
+            new File(getDataPath("ip2region_v4.xdb")), 5 * 1024 * 1024
+        );
+
+        final int[] offsets = new int[]{0, 10, 512, 1024, 39672, 1024 * 1024 * 2};
+        for (int idx : offsets) {
+            final long m2Val = m2Bufer.getUint32(idx);
+            final long m5Val = m5Bufer.getUint32(idx);
+            log.debugf("m2Buffer[%8d:4]: %10d, m5Buffer[%8d:4]: %10d, equals ? %s", idx, m2Val, idx, m5Val, m2Val == m5Val ? "true" : "false");
+        }
+    }
+
+    @Test
+    public void testV4BufferEOF() throws IOException {
+        final LongByteArray buffer = Searcher.loadContentFromFile(
+            new File(getDataPath("ip2region_v4.xdb")), 2 * 1024 * 1024
+        );
+
+        try {
+            buffer.append(new byte[1024]);
+        } catch (IOException e) {
+            log.debugf("failed to append: %s", e.getMessage());
+        }
+    }
+
+    // --- v6
+
     @Test
     public void testV6InputStreamBuffer() throws Exception {
         final LongByteArray cBuffer = Searcher.loadContentFromInputStream(
@@ -35,4 +81,14 @@ public class BufferTest {
         log.debugf("cBuffer->{length:%d, size:%d}", cBuffer.length(), cBuffer.size());
     }
 
+    @Test
+    public void testV6FixedBuffer() throws Exception {
+        final LongByteArray cBuffer = Searcher.loadContentFromFile(
+            new File(getDataPath("ip2region_v6.xdb")), 5 * 1024 * 1024
+        );
+        final Header header = Searcher.loadHeaderFromBuffer(cBuffer);
+        log.debugf("cBuffer->{length:%d, size:%d}", cBuffer.length(), cBuffer.size());
+        log.debugf("Header->%s", header);
+    }
+
 }