How does this code work? Decreasing error bar width using xdata

So I was looking online for a way to decrease error bar width on R2014a and found some code that works perfectly by a David Szotten. However, I still don't understand xdata and how it was used here to achieve what we wanted. Can someone explain this line by line? Here it is reproduced:

function removeErrorBarEnds(hErrBar)
%removeErrorBarEnds
%   removeErrorBarEnds(hErrBar) removes the lines above/below errorbars
%   generated by the MATLAB function hErrBar = errorbar()
%   david szotten

% use length of xdata to find the right handle
% there may be an easier way to do this
dataLen = length( get(hErrBar, 'xdata') );

% objects to try, one of this is the errorbars
candidateList = findall(hErrBar);

for candidate = candidateList(:)'
    candLen = length( get(candidate, 'xdata') );
    % found it
    if candLen == 9 * dataLen
        xOrg = get(candidate, 'xdata');
        yOrg = get(candidate, 'ydata');
        % we only want the first 3 out or every 9
        valuesToExtract = find( kron( ones(1,dataLen), [ones(1,3) zeros(1,6)] ) );
        xNew = xOrg(valuesToExtract);
        yNew = yOrg(valuesToExtract);
        set(candidate, 'xdata', xNew);
        set(candidate, 'ydata', yNew);
    end
end

[yogesh jain]

The coding part is not tough but it seems that it is following any particular algorithm which is a bit tough.