You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: designateCombiningColumns.m
    path of file: ./repos/d4m/matlab_src/@DBtable
    
    the code of the file until where you have to start completion: function designateCombiningColumns(T, colNames, combineType)
%DESIGNATECOMBININGCOLUMNS designates columns with a combiner
%   T table
%   colNames A list of column names in the format "colName1,colName2,"

    
function designateCombiningColumns(T, colNames, combineType)
%DESIGNATECOMBININGCOLUMNS designates columns with a combiner
%   T table
%   colNames A list of column names in the format "colName1,colName2,"
%       where ',' is an arbitrary seperator.  TODO: also accept an array of
%       column names.
%   combineType One of the strings "min", "max", or "sum"
%		IF D4M_API_JAVA.jar is installed on the Accumulo instance, you can
% 		specify "min_decimal", "max_decimal", or "sum_decimal"
%		to obtain the ability to combine on decimals
%The column names do not have to exist when designated. Only one combiner 
%allowed per column. 
%Note this will take into account the current column family.
if nargin < 3
    error('3 input arguments required')
end
T_s = struct(T);
DB_s = struct(T_s.DB);
javaOp = DBaddJavaOps('edu.mit.ll.d4m.db.cloud.D4mDbTableOperations',DB_s.instanceName, DB_s.host, DB_s.user, DB_s.pass, 'Accumulo');
javaOp.designateCombiningColumns(T_s.name, colNames, combineType, T_s.columnfamily)

end