Can I please get a review and a sponsor for a potential fix for JDK-8232879[1]? The patch is available as a webrev at [2].
What's happening in there is that the jdk.nio.zipfs.ZipFileSystem.DeflatingEntryOutputStream is overriding the one arg write(byte b) method and calling the super.write(b) and then doing a crc.update. The super.write(b) (java.util.zip.DeflaterOutputStream in this case) actually internally calls the 3 arg write(b, offset, length) which is overriding by this jdk.nio.zipfs.ZipFileSystem.DeflatingEntryOutputStream. In its implementation of write(b, offset, length), in addition to (rightly) calling super.write(b, offset, length), this method also updates the CRC (again). So this ends up updating the CRC multiple times when the single arg write is invoked. The patch now removes this overridden implementation of write(b) in the DeflatingEntryOutputStream so that the call is handled by the java.util.zip.DeflaterOutputStream. Although there's no @implNote on java.util.zip.DeflaterOutputStream#write(byte b) static that it's (always) going to call the 3 arg write(b, offset, length) method, the implementation as of now does indeed do that. So I guess, its probably OK to rely on that knowledge and get rid of this overridden write(b) method instead of coming up with a bit more complicated fix. The patch also includes a jtreg testcase which reproduces this issues and verifies the fix. [1] https://bugs.openjdk.java.net/browse/JDK-8232879 [2] https://cr.openjdk.java.net/~jpai/webrev/8232879/1/webrev/ -Jaikiran
