Merge pull request #752 from stopit/elasticsearch-sql-jdbc

fix 使用jdbc调用metaData.getColumnCount()函数无法获取正常列数信息的问题 #751

Author: shi-yuan

src/main/java/com/alibaba/druid/pool/ElasticSearchResultSetMetaDataBase.java

@@ -10,8 +10,8 @@
  * Created by allwefantasy on 8/31/16.
  */
 public class ElasticSearchResultSetMetaDataBase extends ResultSetMetaDataBase {
-	
-    private final List<ColumnMetaData> columns = new ArrayList<ColumnMetaData>();
+
+    private final List<ColumnMetaData> columns = super.getColumns();
 
     public ElasticSearchResultSetMetaDataBase(List<String> headers) {
         for(String column:headers){