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Improve performance of StringUtils.replaceEach. - #7494
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## Motivation Improves the performance of `StringUtils.replaceEach` (used in query parameter, path segement and XML escaping), making it linear. ## Changes 1. Remember the next match position of each search string and search for it again only after a replacement has moved past the remembered match. 2. Copy unmatched text between replacements with one bulk append instead of one character at a time. 3. Return the text unchanged when the search list or the replacement list is null. 4. Add a changelog entry for the bugfix. ## Compatibility 1. There is no known compatibility risk. The public API is unchanged and the output is the same as before for every input, including overlapping matches, ties, empty search strings and null replacements. ## Testing New unit tests cover the documented examples, null and empty arguments, the length mismatch exception, overlapping and tied matches, and matches consumed by an earlier replacement. One test runs 20,000 random small inputs through the new code and a copy of the old algorithm and checks that the outputs are equal. Another test replaces 100,000 `&` characters followed by a `<` and checks the result. I ran these tests against the old code, and the large-input timing checks failed there.
alextwoods
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alextwoods
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no-api-surface-area-change
ianbotsf
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Oct 28, 2026
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Motivation
Improves the performance of
StringUtils.replaceEach(used in query parameter, path segement and XML escaping), making it linear.Changes
Compatibility
Testing
New unit tests cover the documented examples, null and empty arguments, the length mismatch exception, overlapping and tied matches, and matches consumed by an earlier replacement. One test runs 20,000 random small inputs through the new code and a copy of the old algorithm and checks that the outputs are equal. Another test replaces 100,000
&characters followed by a<and checks the result. I ran these tests against the old code, and the large-input timing checks failed there.License