[mkgmap-dev] [PATCH v1] Add null handling for Element.copyTags and Element.getTagsWithPrefix

27 Feb 2010

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On 27/02/10 13:23, WanMil wrote:
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/**
    * Copy the tags of the other element.  Only to be used internally
    * by subclasses.
    * @param other The other element.  All its tags will be copied to this
    * element.
    */
public void copyTags(Element other) {
  if (other.tags != null)
      tags = other.tags.copy();
}
So the copyTags does not add but replace all tags. But only if the other
element has tags. This is weird. So I think replaceTags would be a
better name and the other.tags==null case should be handled:
Originally it was used to copy tags from an existing element to a
newly created one, so there wasn't really much of a problem.
This is still mostly the case, except in the multipolygon code which
is no doubt why you are bringing this up :)
So yes, your changes appear fine to me as they will not affect the
original cases. Also the comment about only being used in subclasses
is wrong/out of date.
..Steve
Yeah, I use this in the multipolygon code and stumbled over it.

The patch fixes the copyTags method and adds a null check to the 
getTagsWithPrefix method (which might have been bigger problem).

WanMil