I think this OK. The comments with the o--o did not do much for me though and found them a bit confusing but perhaps I need more coffee this morning ?
Also, not sure we need the @author tag but I think its usage varies in the workspace Best Lance On Mar 19, 2014, at 7:10 PM, David Li wrote: > Hi, > > This is an update from Xerces for file impl/xpath/regex/TokenRange.java. For > details, please refer to: https://bugs.openjdk.java.net/browse/JDK-8035577. > > Webrevs: http://cr.openjdk.java.net/~joehw/jdk9/8035577/webrev/ > > Existing tests: JAXP SQE and unit tests passed. > > Test cases added for typo fix in RangeToken.intersectRanges. Code also > updated to fix a bug where regular expression intersection returns incorrect > value when first range ends later than second range. Example below. Test > cases have been added to cover any scenarios that the code changes affect. > > new RegularExpression("(?[b-d]&[a-r])"); -> returns [b-d] (Correct) > new RegularExpression("(?[a-r]&[b-d])"); -> returns [b-de-r] (Incorrect) > > Thanks, > David > > P.S. Notes on bug fixes. > 1) Line 404 removal of while loop. > This fixes a new bug where incorrect results are given when first range ends > later than second range. In the old code we got > (?[a-r]&[b-d]) -> returns [b-de-r] > By removing the while loop, we get [b-d]. > This while loop looks like a copy-paste error from subtractRanges. In > subtractRanges we need to keep the leftover portion from the first range, but > this does not apply to intersection. > > 2) Line 388, addition of src2 += 2; > This code change affects anything of the form (?[a-r]&[b-eg-j]). The code > execution is diagrammed below. > o------------o (src1) > o--o o--o (src2) > For the first match we get > o------------o (src1) > o--o (src2) > Next we want to run src2+=2 to get the second pair of endpoints (since the > first two endpoints are already used). Notice how src1begin has been updated > to this.ranges[src1] = src2end+1, which is directly from the code. > o------o (src1) > o--o (src2) > The src2+=2 statement was left out of the old code, and is added in this > webrev. If we leave out the src2+=2 at line 388, on the next iteration of > the large while loop we will reach case "} else if (src2end < src1begin) {" > which also executes "src2+=2". This means the correct final result is > generated, but on a later loop. We want to add the new code because it's > better to have all associated variable updated in the sameloop. In addition, > all the other conditions have similar src1 or src2 updates. >
Lance Andersen| Principal Member of Technical Staff | +1.781.442.2037 Oracle Java Engineering 1 Network Drive Burlington, MA 01803 lance.ander...@oracle.com
