AJ-566: fix the connection in connection pool can connect twice

Author: lucaijun

src/com/xxdb/SimpleDBConnectionPool.java

@@ -98,7 +98,8 @@ protected class SimpleDBConnectionPoolImpl {
                 for (int i = 0; i < initialPoolSize; i++) {
                     PoolEntry poolEntry = new PoolEntry(useSSL, compress, usePython, String.format("DolphinDBConnection_%d", i + 1));
                     if (poolEntry.connect(hostName, port, userId, password, initialScript, enableHighAvailability, highAvailabilitySites, reconnect, loadBalance)) {
-                        poolEntry.isFirstLogin.set(false);
+                        poolEntry.isFirstConnect = false;
+                        poolEntry.isFirstLogin = false;
                     }else {
                         log.error(String.format("Connection %s connect failure.", poolEntry.connectionName));
                     }
@@ -160,8 +161,8 @@ boolean isClosed() {
 
     class PoolEntry extends DBConnection {
         AtomicBoolean inUse = new AtomicBoolean(false);
-        AtomicBoolean isFirstConnect = new AtomicBoolean(true);
-        AtomicBoolean isFirstLogin = new AtomicBoolean(true);
+        volatile boolean isFirstConnect = true;
+        volatile boolean isFirstLogin = true;
         String connectionName;
 
         PoolEntry(boolean useSSL, boolean compress, boolean usePython, String connectionName) {
@@ -184,15 +185,15 @@ public void setLoadBalance(boolean loadBalance) {
 
         @Override
         public boolean connect(String hostName, int port, String userId, String password, String initialScript, boolean enableHighAvailability, String[] highAvailabilitySites, boolean reconnect, boolean enableLoadBalance) throws IOException {
-            if (isFirstConnect.compareAndSet(true, false))
+            if (isFirstConnect)
                 return super.connect(hostName, port, userId, password, initialScript, enableHighAvailability, highAvailabilitySites, reconnect, enableLoadBalance);
             else
                 throw new RuntimeException("The connection in connection pool can only connect by pool.");
         }
 
         @Override
         public void login(String userId, String password, boolean enableEncryption) throws IOException {
-            if (isFirstLogin.get())
+            if (isFirstLogin)
                 super.login(userId, password, enableEncryption);
             else
                 throw new RuntimeException("The connection in connection pool can only login by pool.");