code: public static int[] batch(@Nullable PreparedStatement stmt) throws SQLException {
  		int[] rows = EMPTY_INT_ARRAY;
  		if (stmt != null) {
  			rows = stmt.executeBatch();
  			stmt.close();
  		}
  		return rows;
  	}
docs: Execute the {@link PreparedStatement#addBatch() batches}, get the number of rows affected in
  each batch, and close the statement.
  
  @param stmt
  must already have batches added
  @since 1.4.0