extracted buffer value to constant

Author: chernser

client-v2/src/main/java/com/clickhouse/client/api/Client.java

@@ -1072,6 +1072,11 @@ public Client build() {
 
         private static final int DEFAULT_NETWORK_BUFFER_SIZE = 300_000;
 
+        /**
+         * Default size for a buffers used in networking.
+         */
+        public static final int DEFAULT_BUFFER_SIZE = 8192;
+
         private void setDefaults() {
 
             // set default database name if not specified

client-v2/src/main/java/com/clickhouse/client/api/ClientConfigProperties.java

@@ -104,8 +104,7 @@ public enum ClientConfigProperties {
 
     QUERY_ID("query_id"), // actually a server setting, but has client effect too
 
-    CLIENT_NETWORK_BUFFER_SIZE("client_network_buffer_size", "8192"),
-
+    CLIENT_NETWORK_BUFFER_SIZE("client_network_buffer_size", String.valueOf(Client.Builder.DEFAULT_BUFFER_SIZE)),
 
     ACCESS_TOKEN("access_token"), SSL_AUTH("ssl_authentication"),