diff --git a/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTree.java b/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTree.java
index d86facba..4bc11c5d 100644
--- a/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTree.java
+++ b/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTree.java
@@ -285,7 +285,7 @@ public class MerkleTree implements Transactional {
 		if (sn > MAX_SN) {
 			throw new IllegalArgumentException("The sn is great than MAX[" + MAX_SN + "]!");
 		}
-		DataNode dataNode = DataNode.newDataNode(setting.getHashAlgorithm(), sn, key, version, hashedData);
+		DataNode dataNode = MerkleTreeEncoder.newDataNode(setting.getHashAlgorithm(), sn, key, version, hashedData);
 		updatedDataNodes.put(sn, dataNode);
 		return dataNode;
 	}
@@ -844,7 +844,7 @@ public class MerkleTree implements Transactional {
 		if (bytes == null || bytes.length == 0) {
 			return null;
 		}
-		DataNode dataNode = DataNode.parse(bytes);
+		DataNode dataNode = MerkleTreeEncoder.parse(bytes);
 		if (verify && !hashBytes.equals(dataNode.nodeHash)) {
 			String keyStr = hashBytes.toBase58();
 			String actualHashStr = dataNode.nodeHash.toBase58();
@@ -1429,7 +1429,7 @@ public class MerkleTree implements Transactional {
 	 * @author huanghaiquan
 	 *
 	 */
-	private static class DataNode extends AbstractMerkleNode implements MerkleDataNode {
+	static class DataNode extends AbstractMerkleNode implements MerkleDataNode {
 
 		private long sn;
 
@@ -1439,7 +1439,7 @@ public class MerkleTree implements Transactional {
 
 		private byte[] dataNodeBytes;
 
-		private DataNode(long sn, Bytes key, long version, HashDigest dataHash, byte[] dataBytes) {
+		DataNode(long sn, Bytes key, long version, HashDigest dataHash, byte[] dataBytes) {
 			this.sn = sn;
 			this.key = key;
 			this.version = version;
@@ -1447,55 +1447,6 @@ public class MerkleTree implements Transactional {
 			this.dataNodeBytes = dataBytes;
 		}
 
-		@SuppressWarnings("unused")
-		private static DataNode newDataNode(CryptoAlgorithm hashAlgorithm, long sn, Bytes key, long version,
-				byte[] hashedData) {
-			return newDataNode(hashAlgorithm.code(), sn, key, version, hashedData);
-		}
-
-		private static DataNode newDataNode(short hashAlgorithm, long sn, Bytes key, long version, byte[] hashedData) {
-			// byte[] keyStrBytes = BytesUtils.toBytes(key);
-			// int maskSize = NumberMask.SHORT.getMaskLength(keyStrBytes.length);
-			int keySize = key.size();
-			int maskSize = NumberMask.SHORT.getMaskLength(keySize);
-
-			// int bodySize = 8 + maskSize + keyStrBytes.length + 8;// sn + key + version;
-			int bodySize = 8 + maskSize + keySize + 8;// sn + key + version;
-			byte[] bodyBytes = new byte[bodySize];
-
-			int offset = 0;
-			offset += BytesUtils.toBytes(sn, bodyBytes, 0);
-
-			// NumberMask.SHORT.writeMask(keyStrBytes.length, bodyBytes, offset);
-			NumberMask.SHORT.writeMask(keySize, bodyBytes, offset);
-			offset += maskSize;
-
-			// System.arraycopy(keyStrBytes, 0, bodyBytes, offset, keyStrBytes.length);
-			// System.arraycopy(keyStrBytes, 0, bodyBytes, offset, keyStrBytes.length);
-			// offset += keyStrBytes.length;
-			offset += key.copyTo(bodyBytes, offset, keySize);
-
-			// TODO: version;
-			offset += BytesUtils.toBytes(version, bodyBytes, offset);
-
-			byte[] dataBytes = BytesUtils.concat(bodyBytes, hashedData);
-
-			HashFunction hashFunc = Crypto.getHashFunction(hashAlgorithm);
-			HashDigest dataHash = hashFunc.hash(dataBytes);
-
-			int hashMaskSize = NumberMask.TINY.getMaskLength(dataHash.size());
-			int dataNodeSize = bodySize + hashMaskSize + dataHash.size();
-			byte[] dataNodeBytes = new byte[dataNodeSize];
-
-			offset = 0;
-			System.arraycopy(bodyBytes, 0, dataNodeBytes, offset, bodySize);
-			offset += bodySize;
-			NumberMask.TINY.writeMask(dataHash.size(), dataNodeBytes, offset);
-			offset += hashMaskSize;
-			System.arraycopy(dataHash.toBytes(), 0, dataNodeBytes, offset, dataHash.size());
-
-			return new DataNode(sn, key, version, dataHash, dataNodeBytes);
-		}
 
 		@Override
 		protected long getStartingSN() {
@@ -1577,37 +1528,6 @@ public class MerkleTree implements Transactional {
 			return dataNodeBytes;
 		}
 
-		private static DataNode parse(byte[] bytes) {
-			// InputStream in = new ByteArrayInputStream(bytes);
-
-			int offset = 0;
-			long sn = BytesUtils.toLong(bytes, offset);
-			offset += 8;
-
-			// byte[] keyBytes = BytesEncoding.read(NumberMask.SHORT, in);
-			// String key = BytesUtils.toString(keyBytes);
-			int keySize = NumberMask.SHORT.resolveMaskedNumber(bytes, offset);
-			offset += NumberMask.SHORT.getMaskLength(keySize);
-			byte[] keyBytes = new byte[keySize];
-			System.arraycopy(bytes, offset, keyBytes, 0, keySize);
-			offset += keySize;
-			// String key = BytesUtils.toString(keyBytes);
-			Bytes key = new Bytes(keyBytes);
-
-			// long version = BytesUtils.readLong(in);
-			long version = BytesUtils.toLong(bytes, offset);
-			offset += 8;
-
-			// byte[] dataHashBytes = BytesEncoding.read(NumberMask.SHORT, in);
-			int hashSize = NumberMask.TINY.resolveMaskedNumber(bytes, offset);
-			offset += NumberMask.TINY.getMaskLength(hashSize);
-			byte[] dataHashBytes = new byte[hashSize];
-			System.arraycopy(bytes, offset, dataHashBytes, 0, hashSize);
-			offset += hashSize;
-			HashDigest dataHash = new HashDigest(dataHashBytes);
-			return new DataNode(sn, key, version, dataHash, bytes);
-		}
-
 		@Override
 		public int hashCode() {
 			return nodeHash.hashCode();
diff --git a/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTreeEncoder.java b/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTreeEncoder.java
new file mode 100644
index 00000000..d1694717
--- /dev/null
+++ b/source/ledger/ledger-core/src/main/java/com/jd/blockchain/ledger/core/MerkleTreeEncoder.java
@@ -0,0 +1,94 @@
+package com.jd.blockchain.ledger.core;
+
+import com.jd.blockchain.crypto.Crypto;
+import com.jd.blockchain.crypto.CryptoAlgorithm;
+import com.jd.blockchain.crypto.HashDigest;
+import com.jd.blockchain.crypto.HashFunction;
+import com.jd.blockchain.ledger.core.MerkleTree.DataNode;
+import com.jd.blockchain.utils.Bytes;
+import com.jd.blockchain.utils.io.BytesUtils;
+import com.jd.blockchain.utils.io.NumberMask;
+
+public class MerkleTreeEncoder {
+	
+	static DataNode newDataNode(CryptoAlgorithm hashAlgorithm, long sn, Bytes key, long version,
+			byte[] hashedData) {
+		return newDataNode(hashAlgorithm.code(), sn, key, version, hashedData);
+	}
+	
+	static DataNode newDataNode(short hashAlgorithm, long sn, Bytes key, long version, byte[] hashedData) {
+		// byte[] keyStrBytes = BytesUtils.toBytes(key);
+		// int maskSize = NumberMask.SHORT.getMaskLength(keyStrBytes.length);
+		int keySize = key.size();
+		int maskSize = NumberMask.SHORT.getMaskLength(keySize);
+
+		// int bodySize = 8 + maskSize + keyStrBytes.length + 8;// sn + key + version;
+		int bodySize = 8 + maskSize + keySize + 8;// sn + key + version;
+		byte[] bodyBytes = new byte[bodySize];
+
+		int offset = 0;
+		offset += BytesUtils.toBytes(sn, bodyBytes, 0);
+
+		// NumberMask.SHORT.writeMask(keyStrBytes.length, bodyBytes, offset);
+		NumberMask.SHORT.writeMask(keySize, bodyBytes, offset);
+		offset += maskSize;
+
+		// System.arraycopy(keyStrBytes, 0, bodyBytes, offset, keyStrBytes.length);
+		// System.arraycopy(keyStrBytes, 0, bodyBytes, offset, keyStrBytes.length);
+		// offset += keyStrBytes.length;
+		offset += key.copyTo(bodyBytes, offset, keySize);
+
+		// TODO: version;
+		offset += BytesUtils.toBytes(version, bodyBytes, offset);
+
+		byte[] dataBytes = BytesUtils.concat(bodyBytes, hashedData);
+
+		HashFunction hashFunc = Crypto.getHashFunction(hashAlgorithm);
+		HashDigest dataHash = hashFunc.hash(dataBytes);
+
+		int hashMaskSize = NumberMask.TINY.getMaskLength(dataHash.size());
+		int dataNodeSize = bodySize + hashMaskSize + dataHash.size();
+		byte[] dataNodeBytes = new byte[dataNodeSize];
+
+		offset = 0;
+		System.arraycopy(bodyBytes, 0, dataNodeBytes, offset, bodySize);
+		offset += bodySize;
+		NumberMask.TINY.writeMask(dataHash.size(), dataNodeBytes, offset);
+		offset += hashMaskSize;
+		System.arraycopy(dataHash.toBytes(), 0, dataNodeBytes, offset, dataHash.size());
+
+		return new DataNode(sn, key, version, dataHash, dataNodeBytes);
+	}
+	
+	static DataNode parse(byte[] bytes) {
+		// InputStream in = new ByteArrayInputStream(bytes);
+
+		int offset = 0;
+		long sn = BytesUtils.toLong(bytes, offset);
+		offset += 8;
+
+		// byte[] keyBytes = BytesEncoding.read(NumberMask.SHORT, in);
+		// String key = BytesUtils.toString(keyBytes);
+		int keySize = NumberMask.SHORT.resolveMaskedNumber(bytes, offset);
+		offset += NumberMask.SHORT.getMaskLength(keySize);
+		byte[] keyBytes = new byte[keySize];
+		System.arraycopy(bytes, offset, keyBytes, 0, keySize);
+		offset += keySize;
+		// String key = BytesUtils.toString(keyBytes);
+		Bytes key = new Bytes(keyBytes);
+
+		// long version = BytesUtils.readLong(in);
+		long version = BytesUtils.toLong(bytes, offset);
+		offset += 8;
+
+		// byte[] dataHashBytes = BytesEncoding.read(NumberMask.SHORT, in);
+		int hashSize = NumberMask.TINY.resolveMaskedNumber(bytes, offset);
+		offset += NumberMask.TINY.getMaskLength(hashSize);
+		byte[] dataHashBytes = new byte[hashSize];
+		System.arraycopy(bytes, offset, dataHashBytes, 0, hashSize);
+		offset += hashSize;
+		HashDigest dataHash = new HashDigest(dataHashBytes);
+		return new DataNode(sn, key, version, dataHash, bytes);
+	}
+	
+}