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

Author: lucaijun

src/com/xxdb/SimpleDBConnectionPool.java

@@ -97,12 +97,8 @@ protected class SimpleDBConnectionPoolImpl {
             try {
                 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.isFirstConnect = false;
-                        poolEntry.isFirstLogin = false;
-                    }else {
+                    if (!poolEntry.entryConnect(hostName, port, userId, password, initialScript, enableHighAvailability, highAvailabilitySites, reconnect, loadBalance))
                         log.error(String.format("Connection %s connect failure.", poolEntry.connectionName));
-                    }
                     poolEntryArrayList.add(poolEntry);
                 }
                 poolEntries = new CopyOnWriteArrayList<>(poolEntryArrayList);
@@ -162,7 +158,6 @@ boolean isClosed() {
     class PoolEntry extends DBConnection {
         AtomicBoolean inUse = new AtomicBoolean(false);
         volatile boolean isFirstConnect = true;
-        volatile boolean isFirstLogin = true;
         String connectionName;
 
         PoolEntry(boolean useSSL, boolean compress, boolean usePython, String connectionName) {
@@ -183,20 +178,18 @@ public void setLoadBalance(boolean loadBalance) {
             throw new RuntimeException("The loadBalance configuration of connection in connection pool can only be set in SimpleDBConnectionPoolConfig.");
         }
 
+        private boolean entryConnect(String hostName, int port, String userId, String password, String initialScript, boolean enableHighAvailability, String[] highAvailabilitySites, boolean reconnect, boolean enableLoadBalance) throws IOException {
+            return super.connect(hostName, port, userId, password, initialScript, enableHighAvailability, highAvailabilitySites, reconnect, enableLoadBalance);
+        }
+
         @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)
-                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.");
+            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)
-                super.login(userId, password, enableEncryption);
-            else
-                throw new RuntimeException("The connection in connection pool can only login by pool.");
+            throw new RuntimeException("The connection in connection pool can only login by pool.");
         }
 
         @Override

src/com/xxdb/SimpleDBConnectionPoolConfig.java

@@ -137,12 +137,12 @@ protected void validate() {
         userId = getNullIfEmpty(userId);
         if (Objects.isNull(userId)){
             userId = "";
-            log.warn("Log in needs userId.");
+            log.warn("Login needs userId.");
         }
         password = getNullIfEmpty(password);
         if (Objects.isNull(password)){
             password = "";
-            log.warn("Log in needs password.");
+            log.warn("Login needs password.");
         }
         if (initialPoolSize <= 0) {
             initialPoolSize = 5;