Repository: commons-lang Updated Branches: refs/heads/master 274dbfe81 -> 04ca0852b
LANG-1358: Improve StringUtils#replace throughput (closes #300) Motivation: `StringUtils#replace` uses `substring` to append a String region into a StringBuilder. This causes useless copies, as `StringBuilder#append` can take start and end indexes. Modification: Use proper `StringBuilder#append` [overload](https://docs.oracle.com/javase/8/docs/api/java/lang/StringBuilder.html#append-java.lang.CharSequence-int-int-). Result: Based on benchmark from [JOOQâs post](https://blog.jooq.org/2017/10/11/benchmarking-jdk-string-replace-vs-apache-commons-stringutils-replace): Benchmark Mode Cnt Score Error Units StringReplaceBenchmark.testFastStringReplaceLongStringOneMatch thrpt 21 7546534,219 ± 145523,962 ops/s StringReplaceBenchmark.testStringUtilsReplaceLongStringOneMatch thrpt 21 7353512,552 ± 124498,228 ops/s StringReplaceBenchmark.testFastStringReplaceLongStringSeveralMatches thrpt 21 5077255,810 ± 62358,937 ops/s StringReplaceBenchmark.testStringUtilsReplaceLongStringSeveralMatches thrpt 21 4108357,612 ± 92909,038 ops/s StringReplaceBenchmark.testFastStringReplaceShortStringOneMatch thrpt 21 15911221,949 ± 541064,693 ops/s StringReplaceBenchmark.testStringUtilsReplaceShortStringOneMatch thrpt 21 10677897,475 ± 491091,973 ops/s StringReplaceBenchmark.testFastStringReplaceShortStringSeveralMatches thrpt 21 9271742,251 ± 220150,121 ops/s StringReplaceBenchmark.testStringUtilsReplaceShortStringSeveralMatches thrpt 21 6158829,188 ± 99637,607 ops/s Project: http://git-wip-us.apache.org/repos/asf/commons-lang/repo Commit: http://git-wip-us.apache.org/repos/asf/commons-lang/commit/5cb98833 Tree: http://git-wip-us.apache.org/repos/asf/commons-lang/tree/5cb98833 Diff: http://git-wip-us.apache.org/repos/asf/commons-lang/diff/5cb98833 Branch: refs/heads/master Commit: 5cb988334179b4f04a27c59c1e6a888db0dbfc9c Parents: 274dbfe Author: Stephane Landelle <slande...@gatling.io> Authored: Thu Oct 12 10:41:53 2017 +0200 Committer: pascalschumacher <pascalschumac...@gmx.net> Committed: Thu Oct 12 19:31:25 2017 +0200 ---------------------------------------------------------------------- src/main/java/org/apache/commons/lang3/StringUtils.java | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/commons-lang/blob/5cb98833/src/main/java/org/apache/commons/lang3/StringUtils.java ---------------------------------------------------------------------- diff --git a/src/main/java/org/apache/commons/lang3/StringUtils.java b/src/main/java/org/apache/commons/lang3/StringUtils.java index 4af966e..b2b6b72 100644 --- a/src/main/java/org/apache/commons/lang3/StringUtils.java +++ b/src/main/java/org/apache/commons/lang3/StringUtils.java @@ -5515,14 +5515,14 @@ public class StringUtils { increase *= max < 0 ? 16 : max > 64 ? 64 : max; final StringBuilder buf = new StringBuilder(text.length() + increase); while (end != INDEX_NOT_FOUND) { - buf.append(text.substring(start, end)).append(replacement); + buf.append(text, start, end).append(replacement); start = end + replLength; if (--max == 0) { break; } end = searchText.indexOf(searchString, start); } - buf.append(text.substring(start)); + buf.append(text, start, text.length()); return buf.toString(); }
