diff --git a/src/org/redkale/convert/ext/DLongSimpledCoder.java b/src/org/redkale/convert/ext/DLongSimpledCoder.java
index d0f8844d5..d98daad09 100644
--- a/src/org/redkale/convert/ext/DLongSimpledCoder.java
+++ b/src/org/redkale/convert/ext/DLongSimpledCoder.java
@@ -36,7 +36,7 @@ public final class DLongSimpledCoder<R extends Reader, W extends Writer> extends
     public DLong convertFrom(R in) {
         byte[] bs = bsSimpledCoder.convertFrom(in);
         if (bs == null) return null;
-        return new DLong(bs);
+        return DLong.create(bs);
     }
 
 }
diff --git a/src/org/redkale/convert/json/DLongJsonSimpledCoder.java b/src/org/redkale/convert/json/DLongJsonSimpledCoder.java
index a68019866..3c2770f4d 100644
--- a/src/org/redkale/convert/json/DLongJsonSimpledCoder.java
+++ b/src/org/redkale/convert/json/DLongJsonSimpledCoder.java
@@ -29,6 +29,6 @@ public class DLongJsonSimpledCoder extends JsonSimpledCoder<DLong> {
     public DLong convertFrom(JsonReader in) {
         final String str = in.readString();
         if (str == null) return null;
-        return new DLong(Utility.hexToBin(str));
+        return DLong.create(Utility.hexToBin(str));
     }
 }
diff --git a/src/org/redkale/net/sncp/Sncp.java b/src/org/redkale/net/sncp/Sncp.java
index 9536e71a8..fe6fffe05 100644
--- a/src/org/redkale/net/sncp/Sncp.java
+++ b/src/org/redkale/net/sncp/Sncp.java
@@ -95,7 +95,7 @@ public abstract class Sncp {
         synchronized (md5) {
             bytes = md5.digest(bytes);
         }
-        return new DLong(bytes);
+        return DLong.create(bytes);
     }
 
     public static boolean isRemote(Service service) {
diff --git a/src/org/redkale/util/DLong.java b/src/org/redkale/util/DLong.java
index 8f439ae3f..7cf402dc8 100644
--- a/src/org/redkale/util/DLong.java
+++ b/src/org/redkale/util/DLong.java
@@ -27,7 +27,7 @@ public final class DLong extends Number implements Comparable<DLong> {
             (byte) (v2 >> 24), (byte) (v2 >> 16), (byte) (v2 >> 8), (byte) v2};
     }
 
-    public DLong(byte[] bytes) {
+    protected DLong(byte[] bytes) {
         if (bytes == null || bytes.length != 16) throw new NumberFormatException("Not 16 length bytes");
         this.bytes = bytes;
     }
@@ -40,6 +40,11 @@ public final class DLong extends Number implements Comparable<DLong> {
         return bytes;
     }
 
+    public static DLong create(byte[] bytes) {
+        if (ZERO.equals(bytes)) return ZERO;
+        return new DLong(bytes);
+    }
+
     public static DLong read(ByteBuffer buffer) {
         byte[] bs = new byte[16];
         buffer.get(bs);
@@ -71,7 +76,7 @@ public final class DLong extends Number implements Comparable<DLong> {
 
     @Override
     public String toString() {
-        if(this == ZERO) return "0";
+        if (this == ZERO) return "0";
         return new String(Utility.binToHex(bytes));
     }