We make use of jtreg to execute openjdk tests for JDK11/17/21 releases on non-UTF-8 returning platforms. We found latest jtreg code is using Files.newBufferedReader(path) to read group files data(TEST.GROUPS) from openjdk via GroupManager (https://github.com/openjdk/jtreg/blob/master/src/share/classes/com/sun/javatest/regtest/config/GroupManager.java#L102C44-L102C61). This code defaults to return BufferedReader as UTF-8 instance. We see discrepancies when using this version of jtreg on non-UTF-8 platforms where defaultCharset() is non-UTF-8(JDK11 and JDK17).
Hence, we would like to propose a fix of using default.Charset() with Files.newBufferedWriter(Path path, Charset cs) instead of Files.newBufferedReader(path) and Files.readString(Path) to Files.readString(Path,Charset cs) in below jtreg files :
https://github.com/openjdk/jtreg/blob/master/src/share/classes/com/sun/javatest/regtest/config/GroupManager.java#L102C44-L102C61
https://github.com/openjdk/jtreg/blob/master/src/share/classes/com/sun/javatest/regtest/config/ExtraPropDefns.java#L309
We’ve also tested this fix on OpenJDK supported platforms like Linux, Windows, MAC.