Use ArrayList instead of LinkedList for known size [SPR-16378]

[spring-projects-issues]

Philippe Marschall opened SPR-16378 and commented

Spring JDBC unlike other modules uses LinkedList instead of ArrayList in several places. There is a large body of evidence suggesting that on contemporary hardware ArrayList is both faster and has less overhead than even in degenerate cases of empty lists [3] or unknown size.

There are two places in Spring JDBC where the size of the list is known in advance and an ArrayList of the correct final size can be created

[1] https://bugs.java.com/bugdatabase/view_bug.do?bug_id=8011200
[2] http://cliffc.org/blog/2017/11/05/modern-hardware-performance-cache-lines/
[3] https://bugs.openjdk.java.net/browse/JDK-8011200

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Affects: 4.3.13, 5.0.2

Referenced from: pull request #1643, and commits 64af3a0, 91e39d5

Backported to: 4.3.14

[spring-projects-issues]

Juergen Hoeller commented

Good point! Merged for 5.0.3 now and to be backported to 4.3.14 tomorrow.