March 2021 - core-libs-dev

RFR: 8254979: Class.getSimpleName() returns non-empty for lambda and method
by Joe Darcy 17 Mar '21

17 Mar '21

java.lang.Class has a number of methods to return some kind of textual token associated with the class, including a type name, canonical name, simple name, and separately the results of toString(). Bug 8254979 notes that getSimpleName mentions returning the name in source code, but operationally returns a non-null result for synthetic classes, ones without benefit of source code representation. Since it is useful to return a non-null result in such cases, I've updated the spec to mention this case. The names of synthetic classes are not covered by the JLS; using a "$" in such names is customary, but not strictly required. The synthetic classes used to implement lambdas and method references as cited in the bug report include "$"'s. Looking over the other "getFooName" methods, I don't think they need to be updated to handle this case. ------------- Commit messages: - 8254979: Class.getSimpleName() returns non-empty for lambda and method Changes: https://git.openjdk.java.net/jdk/pull/3038/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3038&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8254979 Stats: 10 lines in 1 file changed: 3 ins; 1 del; 6 mod Patch: https://git.openjdk.java.net/jdk/pull/3038.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/3038/head:pull/3038 PR: https://git.openjdk.java.net/jdk/pull/3038

5 5

RFR: 8262807: Note assumptions of core reflection modeling and parameter handling
by Joe Darcy 17 Mar '21

17 Mar '21

Please review the javadoc change below, written in response to recent discussion on core-libs. The bulk of the change is to add a discussion to java.lang.reflect's package-info file about a language vs JVM model for core reflection. That discussion is then linked to from several relevant locations core reflection. A discussion of generic parameter handling is also added along with various small cleanups. I'll update copyright, etc. after agreement on the text is reached. ------------- Commit messages: - Appease jcheck. - 8262807: Note assumptions of core reflection modeling and parameter handling Changes: https://git.openjdk.java.net/jdk/pull/3036/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3036&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8262807 Stats: 90 lines in 4 files changed: 69 ins; 6 del; 15 mod Patch: https://git.openjdk.java.net/jdk/pull/3036.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/3036/head:pull/3036 PR: https://git.openjdk.java.net/jdk/pull/3036

2 6

RFR: 8263726: divideToIntegralValue typo on BigDecimal documentation
by Joe Darcy 17 Mar '21

17 Mar '21

Fix typos in references to the method's name in the javadoc. ------------- Commit messages: - 8263726: divideToIntegralValue typo on BigDecimal documentation Changes: https://git.openjdk.java.net/jdk/pull/3051/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3051&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8263726 Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod Patch: https://git.openjdk.java.net/jdk/pull/3051.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/3051/head:pull/3051 PR: https://git.openjdk.java.net/jdk/pull/3051

2 2

RFR: 8148937: (str) Adapt StringJoiner for Compact Strings
by Сергей Цыпанов 17 Mar '21

17 Mar '21

Hello, as of now `java.util.StringJoiner` still uses `char[]` as a storage for joined Strings. This applies for the cases when all joined Strings as well as delimiter, prefix and suffix contain only ASCII symbols. As a result when `StringJoiner.toString()` is called `byte[]` stored in Strings is inflated in order to fill in `char[]` and after that `char[]` is compressed when constructor of String is called: String delimiter = this.delimiter; char[] chars = new char[this.len + addLen]; int k = getChars(this.prefix, chars, 0); if (size > 0) { k += getChars(elts[0], chars, k); // inflate byte[] for(int i = 1; i < size; ++i) { k += getChars(delimiter, chars, k); k += getChars(elts[i], chars, k); } } k += getChars(this.suffix, chars, k); return new String(chars); // compress char[] -> byte[] This can be improved by utilizing new method `String.getBytes(byte[], int, int, byte, int)` [introduced](https://github.com/openjdk/jdk/pull/402) in [JDK-8224986](https://bugs.openjdk.java.net/browse/JDK-8254082) covering both cases when resulting String is Latin1 or UTF-16 I've prepared a patch along with benchmark proving that this change is correct and brings improvement. @BenchmarkMode(Mode.AverageTime) @OutputTimeUnit(TimeUnit.NANOSECONDS) @Fork(jvmArgsAppend = {"-Xms2g", "-Xmx2g"}) public class StringJoinerBenchmark { @Benchmark public String stringJoiner(Data data) { String[] stringArray = data.stringArray; return Joiner.joinWithStringJoiner(stringArray); } @State(Scope.Thread) public static class Data { @Param({"latin", "cyrillic", "mixed"}) private String mode; @Param({"8", "32", "64"}) private int length; @Param({"5", "10", "100"}) private int count; private String[] stringArray; @Setup public void setup() { RandomStringGenerator generator = new RandomStringGenerator(); stringArray = new String[count]; for (int i = 0; i < count; i++) { String alphabet = getAlphabet(i, mode); stringArray[i] = generator.randomString(alphabet, length); } } private static String getAlphabet(int index, String mode) { var latin = "abcdefghijklmnopqrstuvwxyz"; //English var cyrillic = "абвгдеёжзиклмнопрстуфхцчшщьыъэюя"; // Russian String alphabet; switch (mode) { case "mixed" -> alphabet = index % 2 == 0 ? cyrillic : latin; case "latin" -> alphabet = latin; case "cyrillic" -> alphabet = cyrillic; default -> throw new RuntimeException("Illegal mode " + mode); } return alphabet; } } } (count) (length) (mode) Java 14 patched Units stringJoiner 5 8 latin 78.836 ± 0.208 67.546 ± 0.500 ns/op stringJoiner 5 32 latin 92.877 ± 0.422 66.760 ± 0.498 ns/op stringJoiner 5 64 latin 115.423 ± 0.883 73.224 ± 0.289 ns/op stringJoiner 10 8 latin 152.587 ± 0.429 161.427 ± 0.635 ns/op stringJoiner 10 32 latin 189.998 ± 0.478 164.099 ± 0.963 ns/op stringJoiner 10 64 latin 238.679 ± 1.419 176.825 ± 0.533 ns/op stringJoiner 100 8 latin 1215.612 ± 17.413 1541.802 ± 126.166 ns/op stringJoiner 100 32 latin 1699.998 ± 28.407 1563.341 ± 4.439 ns/op stringJoiner 100 64 latin 2289.388 ± 45.319 2215.931 ± 137.583 ns/op stringJoiner 5 8 cyrillic 96.692 ± 0.947 80.946 ± 0.371 ns/op stringJoiner 5 32 cyrillic 107.806 ± 0.429 84.717 ± 0.541 ns/op stringJoiner 5 64 cyrillic 150.762 ± 2.267 96.214 ± 1.251 ns/op stringJoiner 10 8 cyrillic 190.570 ± 0.381 182.754 ± 0.678 ns/op stringJoiner 10 32 cyrillic 240.239 ± 1.110 187.991 ± 1.575 ns/op stringJoiner 10 64 cyrillic 382.493 ± 2.692 219.358 ± 0.967 ns/op stringJoiner 100 8 cyrillic 1737.435 ± 16.171 1658.379 ± 56.225 ns/op stringJoiner 100 32 cyrillic 2321.106 ± 13.583 1942.028 ± 3.418 ns/op stringJoiner 100 64 cyrillic 3189.563 ± 10.135 2484.796 ± 7.572 ns/op stringJoiner 5 8 mixed 88.743 ± 0.709 76.049 ± 0.685 ns/op stringJoiner 5 32 mixed 103.425 ± 0.745 81.006 ± 0.184 ns/op stringJoiner 5 64 mixed 146.441 ± 0.763 93.071 ± 0.858 ns/op stringJoiner 10 8 mixed 169.262 ± 0.482 158.890 ± 0.598 ns/op stringJoiner 10 32 mixed 218.566 ± 0.945 170.415 ± 1.172 ns/op stringJoiner 10 64 mixed 361.412 ± 1.546 200.374 ± 0.683 ns/op stringJoiner 100 8 mixed 1594.544 ± 5.761 1476.689 ± 2.004 ns/op stringJoiner 100 32 mixed 2221.333 ± 28.320 1879.071 ± 52.729 ns/op stringJoiner 100 64 mixed 3115.786 ± 22.485 2400.644 ± 4.401 ns/op stringJoiner:·gc.alloc.rate.norm 5 8 latin 248.023 ± 0.001 136.015 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 32 latin 608.045 ± 0.001 256.022 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 64 latin 1088.067 ± 0.002 416.030 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 8 latin 464.044 ± 0.001 264.029 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 32 latin 1184.085 ± 0.003 504.044 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 64 latin 2144.123 ± 0.005 824.065 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 100 8 latin 3872.367 ± 8.002 2024.269 ± 8.016 B/op stringJoiner:·gc.alloc.rate.norm 100 32 latin 11048.803 ± 7.988 4416.393 ± 0.004 B/op stringJoiner:·gc.alloc.rate.norm 100 64 latin 20657.194 ± 9.775 7640.642 ± 9.819 B/op stringJoiner:·gc.alloc.rate.norm 5 8 cyrillic 360.029 ± 0.001 184.020 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 32 cyrillic 960.060 ± 0.002 424.032 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 64 cyrillic 1760.088 ± 0.003 744.043 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 8 cyrillic 664.063 ± 0.001 352.038 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 32 cyrillic 1864.128 ± 0.003 832.067 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 64 cyrillic 3464.206 ± 0.007 1472.094 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 100 8 cyrillic 5704.541 ± 0.006 2928.317 ± 8.002 B/op stringJoiner:·gc.alloc.rate.norm 100 32 cyrillic 17705.090 ± 0.045 7720.658 ± 0.007 B/op stringJoiner:·gc.alloc.rate.norm 100 64 cyrillic 33689.855 ± 9.786 14121.042 ± 0.015 B/op stringJoiner:·gc.alloc.rate.norm 5 8 mixed 360.028 ± 0.001 184.016 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 32 mixed 960.059 ± 0.002 424.031 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 5 64 mixed 1760.088 ± 0.003 744.041 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 8 mixed 664.052 ± 0.001 352.035 ± 0.002 B/op stringJoiner:·gc.alloc.rate.norm 10 32 mixed 1864.116 ± 0.005 832.064 ± 0.001 B/op stringJoiner:·gc.alloc.rate.norm 10 64 mixed 3464.196 ± 0.006 1472.088 ± 0.002 B/op stringJoiner:·gc.alloc.rate.norm 100 8 mixed 5672.448 ± 8.002 2920.314 ± 0.006 B/op stringJoiner:·gc.alloc.rate.norm 100 32 mixed 17681.092 ± 9.824 7728.653 ± 8.008 B/op stringJoiner:·gc.alloc.rate.norm 100 64 mixed 33697.818 ± 8.011 14120.977 ± 0.034 B/op ------------- Commit messages: - 8261880: Check also delimiter, prefix and suffix - 8148937: (str) Adapt StringJoiner for Compact Strings Changes: https://git.openjdk.java.net/jdk/pull/2627/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2627&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8148937 Stats: 77 lines in 3 files changed: 56 ins; 6 del; 15 mod Patch: https://git.openjdk.java.net/jdk/pull/2627.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2627/head:pull/2627 PR: https://git.openjdk.java.net/jdk/pull/2627

3 13

RFR: 8259925: [Vector API] Unreasonable IndexOutOfBoundsException message when length < vlen
by Jie Fu 17 Mar '21

17 Mar '21

Hi all, For this reproducer: import jdk.incubator.vector.ByteVector; import jdk.incubator.vector.VectorSpecies; public class Test { static final VectorSpecies<Byte> SPECIES_128 = ByteVector.SPECIES_128; static byte[] a = new byte[8]; static byte[] b = new byte[8]; public static void main(String[] args) { ByteVector av = ByteVector.fromArray(SPECIES_128, a, 0); av.intoArray(b, 0); System.out.println("b: " + b[0]); } } The following IndexOutOfBoundsException message (length -7) is unreasonable. Exception in thread "main" java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length -7 It might be better to fix it like this. Exception in thread "main" java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0 Thanks. Best regards, Jie ------------- Commit messages: - 8259925: [Vector API] Unreasonable IndexOutOfBoundsException message when length < vlen Changes: https://git.openjdk.java.net/jdk/pull/2127/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2127&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8259925 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/2127.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2127/head:pull/2127 PR: https://git.openjdk.java.net/jdk/pull/2127

2 12

RFR: 8263536: Add missing @compile tags to jpackage tests
by Alexey Semenyuk 16 Mar '21

16 Mar '21

8263536: Add missing @compile tags to jpackage tests ------------- Commit messages: - 8263536: Add missing @compile tags to jpackage tests Changes: https://git.openjdk.java.net/jdk/pull/2975/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2975&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8263536 Stats: 15 lines in 14 files changed: 13 ins; 2 del; 0 mod Patch: https://git.openjdk.java.net/jdk/pull/2975.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2975/head:pull/2975 PR: https://git.openjdk.java.net/jdk/pull/2975

6 15

RFR: JDK-8248904: Add support to jpackage for the Mac App Store
by Andy Herrick 16 Mar '21

16 Mar '21

Implementation of Mac App Support including three new mac specific CLI options. ------------- Commit messages: - JDK-8248904: Add support for Mac App Store - JDK-8248904: Add support for Mac App Store - JDK-8248904: Add support for Mac App Store - JDK-8248904: Add support for Mac App Store - JDK-8248904: Add support for Mac App Store - JDK-8248904: Add support for Mac App Store Changes: https://git.openjdk.java.net/jdk/pull/2716/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2716&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8248904 Stats: 310 lines in 23 files changed: 205 ins; 41 del; 64 mod Patch: https://git.openjdk.java.net/jdk/pull/2716.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2716/head:pull/2716 PR: https://git.openjdk.java.net/jdk/pull/2716

5 7

RFR: 8263450: Simplify LambdaForm.useCount
by Claes Redestad 16 Mar '21

16 Mar '21

Simplify useCount and avoid calling lastUseIndex for a small startup win. ------------- Commit messages: - Simplify LambdaForm.useCount Changes: https://git.openjdk.java.net/jdk/pull/2940/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2940&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8263450 Stats: 16 lines in 1 file changed: 4 ins; 6 del; 6 mod Patch: https://git.openjdk.java.net/jdk/pull/2940.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2940/head:pull/2940 PR: https://git.openjdk.java.net/jdk/pull/2940

2 3

RFR: 8263509: LdapSchemaParser.readNextTag checks array length incorrectly
by Aleksey Shipilev 16 Mar '21

16 Mar '21

SonarCloud rightfully says: The length of "values" is always ">=0", so update this test to either "==0" or ">0". // make sure at least one value was returned if(values.length < 0) { // <--- here throw new InvalidAttributeValueException("no values for " + "attribute "" + tagName + """); } There is a subsequent access to values[0], which means the failure would throw `AIOOB`, not `InvalidAttributeValueException`. Additional testing: - [x] Linux x86_64 fastdebug, `com/sun/jndi` ------------- Commit messages: - 8263509: LdapSchemaParser.readNextTag checks array length incorrectly Changes: https://git.openjdk.java.net/jdk/pull/2968/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2968&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8263509 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/2968.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/2968/head:pull/2968 PR: https://git.openjdk.java.net/jdk/pull/2968

4 7

RFR: 8080272 Refactor I/O stream copying to use java.io.InputStream.transferTo
by Andrey Turbanov 16 Mar '21

16 Mar '21

8080272 Refactor I/O stream copying to use java.io.InputStream.transferTo ------------- Commit messages: - 8080272: Refactor I/O stream copying to use java.io.InputStream.transferTo - 8080272: Refactor I/O stream copying to use java.io.InputStream.transferTo Changes: https://git.openjdk.java.net/jdk/pull/1853/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=1853&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8080272 Stats: 319 lines in 26 files changed: 1 ins; 248 del; 70 mod Patch: https://git.openjdk.java.net/jdk/pull/1853.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/1853/head:pull/1853 PR: https://git.openjdk.java.net/jdk/pull/1853

10 57