On close() check if underlying connection is closed (#73)

* On close() check if underlying connection is closed

Author: rob-bygrave

ebean-datasource/src/main/java/io/ebean/datasource/pool/ConnectionPool.java

@@ -601,6 +601,10 @@ void returnConnectionForceClose(PooledConnection pooledConnection) {
     returnTheConnection(pooledConnection, true);
   }
 
+  void removeClosedConnection(PooledConnection pooledConnection) {
+    queue.returnPooledConnection(pooledConnection, true);
+  }
+
   /**
    * Return connection. If forceClose is true then this is a bad connection that
    * must be removed and closed fully.

ebean-datasource/src/main/java/io/ebean/datasource/pool/PooledConnection.java

@@ -394,6 +394,10 @@ public void close() throws SQLException {
     }
 
     try {
+      if (connection.isClosed()) {
+        pool.removeClosedConnection(this);
+        return;
+      }
       // reset the autoCommit back if client code changed it
       if (resetAutoCommit) {
         connection.setAutoCommit(pool.isAutoCommit());