diff --git a/HISTORY b/HISTORY
index 62e6193..ea9fcb8 100644
--- a/HISTORY
+++ b/HISTORY
@@ -1,4 +1,7 @@
 
+Version 1.39  2025-12-18
+  * ConnectionPool.getKey() use '-' instead of ':'
+
 Version 1.38  2025-11-28
   * bugfixed: loadStorageServersFromTracker correctly with rw option
   * throw IOException with msg "connection broken" when in.read() < 0
diff --git a/build.xml b/build.xml
index 29a2337..f328c62 100644
--- a/build.xml
+++ b/build.xml
@@ -4,7 +4,7 @@
 
   <target name="init">
     <property name="project.name" value="fastdfs-client-java"/>
-    <property name="project.version" value="1.27-SNAPSHOT"/>
+    <property name="project.version" value="1.38-SNAPSHOT"/>
     <property name="project.java" value="${basedir}/src/main/java"/>
     <property name="project.resources" value="${basedir}/src/main/resources"/>
     <property name="project.build" value="${basedir}/build"/>
diff --git a/src/main/java/org/csource/fastdfs/pool/Connection.java b/src/main/java/org/csource/fastdfs/pool/Connection.java
index 695b4ea..d12cc03 100644
--- a/src/main/java/org/csource/fastdfs/pool/Connection.java
+++ b/src/main/java/org/csource/fastdfs/pool/Connection.java
@@ -97,6 +97,7 @@ public class Connection {
         }
         return isConnected;
     }
+
     public boolean isAvaliable() {
         if (isConnected()) {
             if (sock.getPort() == 0) {
diff --git a/src/main/java/org/csource/fastdfs/pool/ConnectionFactory.java b/src/main/java/org/csource/fastdfs/pool/ConnectionFactory.java
index 9e49dee..f1458a0 100644
--- a/src/main/java/org/csource/fastdfs/pool/ConnectionFactory.java
+++ b/src/main/java/org/csource/fastdfs/pool/ConnectionFactory.java
@@ -23,7 +23,8 @@ public class ConnectionFactory {
             sock.connect(socketAddress, ClientGlobal.g_connect_timeout);
             return new Connection(sock, socketAddress);
         } catch (Exception e) {
-            throw new MyException("connect to server " + socketAddress.getAddress().getHostAddress() + ":" + socketAddress.getPort() + " fail, emsg: " + e.getMessage());
+            throw new MyException("connect to server " + socketAddress.getAddress().getHostAddress()
+                    + ":" + socketAddress.getPort() + " fail, emsg: " + e.getMessage());
         }
     }
 }
diff --git a/src/main/java/org/csource/fastdfs/pool/ConnectionManager.java b/src/main/java/org/csource/fastdfs/pool/ConnectionManager.java
index a4ecfc3..0200bbe 100644
--- a/src/main/java/org/csource/fastdfs/pool/ConnectionManager.java
+++ b/src/main/java/org/csource/fastdfs/pool/ConnectionManager.java
@@ -115,7 +115,6 @@ public class ConnectionManager {
         } finally {
             lock.unlock();
         }
-
     }
 
     public void closeConnection(Connection connection) {
diff --git a/src/main/java/org/csource/fastdfs/pool/ConnectionPool.java b/src/main/java/org/csource/fastdfs/pool/ConnectionPool.java
index ec3820d..33796fa 100644
--- a/src/main/java/org/csource/fastdfs/pool/ConnectionPool.java
+++ b/src/main/java/org/csource/fastdfs/pool/ConnectionPool.java
@@ -43,7 +43,6 @@ public class ConnectionPool {
         } else {
             connection.closeDirectly();
         }
-
     }
 
     public static void closeConnection(Connection connection) throws IOException {
@@ -64,7 +63,7 @@ public class ConnectionPool {
         if (socketAddress == null) {
             return null;
         }
-        return String.format("%s:%s", socketAddress.getAddress().getHostAddress(), socketAddress.getPort());
+        return String.format("%s-%s", socketAddress.getAddress().getHostAddress(), socketAddress.getPort());
     }
 
     @Override