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EObjectAtOffsetHelper.internalResolveElementAt method is not null safe [message #723484]

Thu, 08 September 2011 16:28

Mary Komor

Messages: 61
Registered: July 2009

Member

EObjectAtOffsetHelper.internalResolveElementAt makes a call to
NodeModelUtils.findLeafNodeAtOffset, which could return null, but it does
not do a null check of the result and results in an NPE. I got this to
happen when my cursor was at the very end of my file (the resulting offset
was equal to the length of the root node). Should there be a null check? The
workaround I have put into my code is to check the offset that I am asking
to be resolved -- if it is equal to the total length of the root node, then
I decrease it by 1.

Here's the snippet of code in EObjectAtOffsetHelper.internalResolveElementAt

ILeafNode leaf =
NodeModelUtils.findLeafNodeAtOffset(parseResult.getRootNode(), offset);
if(leaf.isHidden() && leaf.getOffset() == offset) {
leaf = NodeModelUtils.findLeafNodeAtOffset(parseResult.getRootNode(),
offset - 1);
}

Mary

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