Zero-allocation hashing for Java

Add an interface LongTupleHashFunction which extends the 64-bit LongHashFunction. The new interface add two sets of APIs while keeping compatible to the original long API:

1. long hash(..., long[] result);
2. long[] hashTuple(...);

Among three sets of the hash API, the real work will appear in the long hash(..., long[] result) style functions which should returns result[0] as the direct result. The other sets can be deduced from this style ones.

In the mean time, the implementation of LongTupleHashFunction must override bits() function providing the real bits of this function. The result of bits() should be larger than 64, but don't have to be divided by 64.

I choose long[] for the result container since it is very simple and can be optimized by JIT. When developing a long hash(..., long[] result), we just need to check if the result is null, which means omitting the full result, and don't have to checkresult.length(). LongTupleHashFunction provides a newLongTuple() function to alloc a correct array based on bits().

Since a result container can be easily reused within one thread, so the cost of allocation could trend to zero.

Murmur3F 128-bit has been migrated to `LongTupleHashFunction'.

I cannot run xxHash on devices running android 6. Stacktrace:

java.lang.NoSuchMethodError: No virtual method getByte(Ljava/lang/Object;J)B in class Lsun/misc/Unsafe; or its super classes (declaration of 'sun.misc.Unsafe' appears in /system/framework/core-libart.jar)
        at net.openhft.hashing.UnsafeAccess.getByte(UnsafeAccess.java:87)
        at net.openhft.hashing.UnsafeAccess.getUnsignedByte(UnsafeAccess.java:82)
        at net.openhft.hashing.XxHash.fetch8(XxHash.java:51)
        at net.openhft.hashing.XxHash.xxHash64(XxHash.java:150)
        at net.openhft.hashing.XxHash$AsLongHashFunction.hash(XxHash.java:272)
        at net.openhft.hashing.LongHashFunction.unsafeHash(LongHashFunction.java:453)
        at net.openhft.hashing.LongHashFunction.hashBytes(LongHashFunction.java:494)

See:

• https://search.maven.org/artifact/net.openhft/zero-allocation-hashing
• https://mvnrepository.com/artifact/net.openhft/zero-allocation-hashing

Also, a changelog would be welcome since https://github.com/OpenHFT/Zero-Allocation-Hashing/releases doesn't include the actual releases and the readme contains old refrences to versions:

and and

zero-allocation-hashing version: 0.12 java version: 14 jvm: openjdk

We are experiencing class loading deadlock when using concurrently LongTupleHashFunction and LongHashFunction, here is the thread dump of the app when the deadlock occurs:

"default.work-dispatcher-39" #98 prio=5 os_prio=0 cpu=1399.65ms elapsed=747.54s tid=0x00007f54fc07b000 nid=0x7a in Object.wait()  [0x00007f540f4f2000]
   java.lang.Thread.State: RUNNABLE
        at net.openhft.hashing.LongHashFunction.murmur_3(LongHashFunction.java:223)
        - waiting on the Class initialization monitor for net.openhft.hashing.MurmurHash_3
        (...)
"default.work-dispatcher-48" #108 prio=5 os_prio=0 cpu=2235.06ms elapsed=747.42s tid=0x00007f5410038000 nid=0x84 in Object.wait()  [0x00007f540e4b5000]
   java.lang.Thread.State: RUNNABLE
        at net.openhft.hashing.LongHashFunction.murmur_3(LongHashFunction.java:223)
        - waiting on the Class initialization monitor for net.openhft.hashing.MurmurHash_3
        (...)
"default.work-dispatcher-50" #109 prio=5 os_prio=0 cpu=211.69ms elapsed=747.42s tid=0x00007f541003c000 nid=0x85 in Object.wait()  [0x00007f540e3b2000]
   java.lang.Thread.State: RUNNABLE
        at net.openhft.hashing.CompactLatin1CharSequenceAccess.<clinit>(CompactLatin1CharSequenceAccess.java:83)
        - waiting on the Class initialization monitor for net.openhft.hashing.UnsafeAccess
        at net.openhft.hashing.ModernCompactStringHash.<clinit>(ModernCompactStringHash.java:14)
        at net.openhft.hashing.Util.<clinit>(Util.java:41)
        at net.openhft.hashing.MurmurHash_3.<clinit>(MurmurHash_3.java:38)
        at net.openhft.hashing.LongHashFunction.murmur_3(LongHashFunction.java:223)
        (...)
"default.work-dispatcher-103" #195 prio=5 os_prio=0 cpu=378.90ms elapsed=727.08s tid=0x00007f54c8009800 nid=0xe1 in Object.wait()  [0x00007f539fdc6000]
   java.lang.Thread.State: RUNNABLE
        at net.openhft.hashing.UnsafeAccess.<clinit>(UnsafeAccess.java:30)
        - waiting on the Class initialization monitor for net.openhft.hashing.Util
        at net.openhft.hashing.LongTupleHashFunction.<clinit>(LongTupleHashFunction.java:948)
        (...)

NB: I have sanitised the stack traces to remove mention of our own classes.

Hello! I'd like to be able to hash parts of a long string without having to copy them into a separate StringBuilder / String etc.. For this I'd like to be able to implement CharSequence in order to present the chars I would like to hash.

The public methods for LongHashFunction only accept String and StringBuilder which are final. However there is the package private method: long hashNativeChars(CharSequence input) in LongHashFunction.java which would provide that. Is there a reason why it cannot be made public to allow access from other packages to it? (without ofc resorting to accessing it through the private-package scope). That would be really great. Thanks!

1. move the byte order converting logic into Primitives and Access class
2. replace common fetch* methods in hash class by the Access short api

After refactoring, the hashing functions could only care about the calculations in static methods and create suitable LongHashFunction/LongTupleHashFunction instances.

Using the library on some Android versions results in following Error:

java.lang.NoSuchMethodError: No virtual method getByte(Ljava/lang/Object;J)B in class Lsun/misc/Unsafe; or its super classes (declaration of 'sun.misc.Unsafe' appears in /system/framework/core-libart.jar)
                  at net.openhft.hashing.LongHashFunction.<clinit>(LongHashFunction.java:73)

It does work on Android 7. It seems, older Android versions do not implement full functionality of Unsafe.

Considering that Unsafe is likely to be replaced/killed off in future versions of mainline Java, you should probably move all related static constants into the UnsafeAccess and add some handling for situations when it is not available.

[INFO] --- maven-release-plugin:3.0.0-M1:perform (default-cli) @ zero-allocation-hashing ---
[INFO] phase verify-release-configuration
[INFO] starting perform goal, composed of 3 phases: verify-completed-prepare-phases, checkout-project-from-scm, run-perform-goals
[INFO] [perform] 1/3 verify-completed-prepare-phases
[INFO] [perform] 2/3 checkout-project-from-scm
[INFO] Checking out the project to perform the release ...
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  20.289 s
[INFO] Finished at: 2021-06-19T16:27:05+02:00
[INFO] ------------------------------------------------------------------------
[WARNING] The requested profile "guarded" could not be activated because it does not exist.
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-release-plugin:3.0.0-M1:perform (default-cli) on project zero-allocation-hashing: Execution default-cli of goal org.apache.maven.plugins:maven-release-plugin:3.0.0-M1:perform failed: An API incompatibility was encountered while executing org.apache.maven.plugins:maven-release-plugin:3.0.0-M1:perform: java.lang.AbstractMethodError: org.apache.maven.scm.command.checkout.AbstractCheckOutCommand.executeCheckOutCommand(Lorg/apache/maven/scm/provider/ScmProviderRepository;Lorg/apache/maven/scm/ScmFileSet;Lorg/apache/maven/scm/ScmVersion;ZZ)Lorg/apache/maven/scm/command/checkout/CheckOutScmResult;
[ERROR] -----------------------------------------------------
[ERROR] realm =    plugin>org.apache.maven.plugins:maven-release-plugin:3.0.0-M1
[ERROR] strategy = org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy
[ERROR] urls[0] = file:/home/teamcity/.m2/repository/org/apache/maven/plugins/maven-release-plugin/3.0.0-M1/maven-release-plugin-3.0.0-M1.jar
[ERROR] urls[1] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-gitexe/1.8.1/maven-scm-provider-gitexe-1.8.1.jar
[ERROR] urls[2] = file:/home/teamcity/.m2/repository/regexp/regexp/1.3/regexp-1.3.jar
[ERROR] urls[3] = file:/home/teamcity/.m2/repository/commons-io/commons-io/2.2/commons-io-2.2.jar
[ERROR] urls[4] = file:/home/teamcity/.m2/repository/commons-lang/commons-lang/2.6/commons-lang-2.6.jar
[ERROR] urls[5] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-git-commons/1.8.1/maven-scm-provider-git-commons-1.8.1.jar
[ERROR] urls[6] = file:/home/teamcity/.m2/repository/org/sonatype/sisu/sisu-inject-bean/1.4.2/sisu-inject-bean-1.4.2.jar
[ERROR] urls[7] = file:/home/teamcity/.m2/repository/org/sonatype/sisu/sisu-guice/2.1.7/sisu-guice-2.1.7-noaop.jar
[ERROR] urls[8] = file:/home/teamcity/.m2/repository/org/apache/maven/release/maven-release-manager/3.0.0-M1/maven-release-manager-3.0.0-M1.jar
[ERROR] urls[9] = file:/home/teamcity/.m2/repository/org/apache/maven/release/maven-release-api/3.0.0-M1/maven-release-api-3.0.0-M1.jar
[ERROR] urls[10] = file:/home/teamcity/.m2/repository/org/codehaus/plexus/plexus-interactivity-api/1.0-alpha-6/plexus-interactivity-api-1.0-alpha-6.jar
[ERROR] urls[11] = file:/home/teamcity/.m2/repository/org/codehaus/plexus/plexus-interpolation/1.14/plexus-interpolation-1.14.jar
[ERROR] urls[12] = file:/home/teamcity/.m2/repository/org/sonatype/plexus/plexus-sec-dispatcher/1.3/plexus-sec-dispatcher-1.3.jar
[ERROR] urls[13] = file:/home/teamcity/.m2/repository/org/sonatype/plexus/plexus-cipher/1.4/plexus-cipher-1.4.jar
[ERROR] urls[14] = file:/home/teamcity/.m2/repository/org/apache/maven/shared/maven-invoker/2.2/maven-invoker-2.2.jar
[ERROR] urls[15] = file:/home/teamcity/.m2/repository/org/apache/commons/commons-lang3/3.7/commons-lang3-3.7.jar
[ERROR] urls[16] = file:/home/teamcity/.m2/repository/commons-cli/commons-cli/1.2/commons-cli-1.2.jar
[ERROR] urls[17] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-providers-standard/1.11.2/maven-scm-providers-standard-1.11.2.pom
[ERROR] urls[18] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-accurev/1.11.2/maven-scm-provider-accurev-1.11.2.jar
[ERROR] urls[19] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-bazaar/1.11.2/maven-scm-provider-bazaar-1.11.2.jar
[ERROR] urls[20] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-clearcase/1.11.2/maven-scm-provider-clearcase-1.11.2.jar
[ERROR] urls[21] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-cvsexe/1.11.2/maven-scm-provider-cvsexe-1.11.2.jar
[ERROR] urls[22] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-cvs-commons/1.11.2/maven-scm-provider-cvs-commons-1.11.2.jar
[ERROR] urls[23] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-cvsjava/1.11.2/maven-scm-provider-cvsjava-1.11.2.jar
[ERROR] urls[24] = file:/home/teamcity/.m2/repository/org/netbeans/lib/cvsclient/20060125/cvsclient-20060125.jar
[ERROR] urls[25] = file:/home/teamcity/.m2/repository/ch/ethz/ganymed/ganymed-ssh2/build210/ganymed-ssh2-build210.jar
[ERROR] urls[26] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-jgit/1.11.2/maven-scm-provider-jgit-1.11.2.jar
[ERROR] urls[27] = file:/home/teamcity/.m2/repository/org/eclipse/jgit/org.eclipse.jgit/4.5.4.201711221230-r/org.eclipse.jgit-4.5.4.201711221230-r.jar
[ERROR] urls[28] = file:/home/teamcity/.m2/repository/com/jcraft/jsch/0.1.53/jsch-0.1.53.jar
[ERROR] urls[29] = file:/home/teamcity/.m2/repository/com/googlecode/javaewah/JavaEWAH/0.7.9/JavaEWAH-0.7.9.jar
[ERROR] urls[30] = file:/home/teamcity/.m2/repository/org/apache/httpcomponents/httpclient/4.3.6/httpclient-4.3.6.jar
[ERROR] urls[31] = file:/home/teamcity/.m2/repository/org/apache/httpcomponents/httpcore/4.3.3/httpcore-4.3.3.jar
[ERROR] urls[32] = file:/home/teamcity/.m2/repository/commons-logging/commons-logging/1.1.3/commons-logging-1.1.3.jar
[ERROR] urls[33] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-hg/1.11.2/maven-scm-provider-hg-1.11.2.jar
[ERROR] urls[34] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-perforce/1.11.2/maven-scm-provider-perforce-1.11.2.jar
[ERROR] urls[35] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-starteam/1.11.2/maven-scm-provider-starteam-1.11.2.jar
[ERROR] urls[36] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-svnexe/1.11.2/maven-scm-provider-svnexe-1.11.2.jar
[ERROR] urls[37] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-synergy/1.11.2/maven-scm-provider-synergy-1.11.2.jar
[ERROR] urls[38] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-vss/1.11.2/maven-scm-provider-vss-1.11.2.jar
[ERROR] urls[39] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-tfs/1.11.2/maven-scm-provider-tfs-1.11.2.jar
[ERROR] urls[40] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-integrity/1.11.2/maven-scm-provider-integrity-1.11.2.jar
[ERROR] urls[41] = file:/home/teamcity/.m2/repository/com/mks/api/mksapi-jar/4.10.9049/mksapi-jar-4.10.9049.jar
[ERROR] urls[42] = file:/home/teamcity/.m2/repository/org/codehaus/groovy/groovy-all/1.7.6/groovy-all-1.7.6.jar
[ERROR] urls[43] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-jazz/1.11.2/maven-scm-provider-jazz-1.11.2.jar
[ERROR] urls[44] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-manager-plexus/1.8/maven-scm-manager-plexus-1.8.jar
[ERROR] urls[45] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-provider-svn-commons/1.11.2/maven-scm-provider-svn-commons-1.11.2.jar
[ERROR] urls[46] = file:/home/teamcity/.m2/repository/org/apache/maven/shared/maven-artifact-transfer/0.9.1/maven-artifact-transfer-0.9.1.jar
[ERROR] urls[47] = file:/home/teamcity/.m2/repository/org/apache/maven/shared/maven-common-artifact-filters/3.0.1/maven-common-artifact-filters-3.0.1.jar
[ERROR] urls[48] = file:/home/teamcity/.m2/repository/org/apache/maven/shared/maven-shared-utils/3.1.0/maven-shared-utils-3.1.0.jar
[ERROR] urls[49] = file:/home/teamcity/.m2/repository/commons-codec/commons-codec/1.6/commons-codec-1.6.jar
[ERROR] urls[50] = file:/home/teamcity/.m2/repository/org/sonatype/aether/aether-util/1.7/aether-util-1.7.jar
[ERROR] urls[51] = file:/home/teamcity/.m2/repository/org/codehaus/plexus/plexus-component-annotations/1.7.1/plexus-component-annotations-1.7.1.jar
[ERROR] urls[52] = file:/home/teamcity/.m2/repository/org/apache/maven/scm/maven-scm-api/1.11.2/maven-scm-api-1.11.2.jar
[ERROR] urls[53] = file:/home/teamcity/.m2/repository/org/codehaus/plexus/plexus-utils/3.0.15/plexus-utils-3.0.15.jar
[ERROR] urls[54] = file:/home/teamcity/.m2/repository/org/jdom/jdom/1.1/jdom-1.1.jar
[ERROR] Number of foreign imports: 1
[ERROR] import: Entry[import  from realm ClassRealm[project>net.openhft:zero-allocation-hashing:0.15-SNAPSHOT, parent: ClassRealm[maven.api, parent: null]]]
[ERROR] 
[ERROR] -----------------------------------------------------
[ERROR] 
[ERROR] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginContainerException
[teamcity@teamcity Zero-Allocation-Hashing]$ 

After Clone the repository I try to build this project in IDEA with JDK8. I receive a error in file src/main/java-stub/java/lang/Math.java because JDK8 don't have Math.multiplyHigh and try-catch can't handle this.

detect unalign offsets in runtime. this may take in a little performance cost, but should work. all ut cases are designed for little endian machines.

Close #36

Hey,

I'm trying to avoid using off-heap Map/Set implementations for performance reasons (serialization/deserialization) and a good way of doing that is using Long instead of String for UUID like keys and using some Map implementation that doesn't autobox primitives...

I'm just wondering what is the most suitable 64bit hash function? I'm mostly going for the lowest collision rate rather than for performance. I'd just like to have a HashMap/HashSet with up to 30-40M records with the least memory footprint possible without GC overhead and test it for presence of 400M distinct UUIDs. I have no idea what collision rate could be there if I use say murmur3 for 64bit hashing of those UUIDs.

I'm very grateful for your library, it is the only source of 64bit hash functions. I'm kind of terrified of using Guava's 128bit hash functions and then calling : http://google.github.io/guava/releases/snapshot/api/docs/com/google/common/hash/HashCode.html#padToLong--

I tested my implementation for Java 9+ with VarHandles instead of Unsafe. In my test case (hashing multiple files with a total size of ~ 1 GB) I noticed a huge speed improvement

• XxHash: Unsafe 1220 ms vs VarHandle 630 ms
• XxHash3: Unsafe 1280 ms vs VarHandle 720 ms

Is it possible to publish separate version for modern JDKs without dependency on Unsafe?

according to travis notice:

Please be aware travis-ci.org will be shutting down in several weeks, with all accounts migrating to travis-ci.com. Please stay tuned here for more information.

Hi,

I have it only on android device: Samsung Galaxy J5 (SM-J530F), but possibly there are other devices affected.

We have fatal crash that always happens when trying to hash byte array (contents does not seem to matter) using xxHash:

LongHashFunction
        .xx().hashBytes(value)

Taken from LogCat:

    --------- beginning of crash
2020-03-12 12:07:08.966 16010-16280/? A/libc: Fatal signal 7 (SIGBUS), code 1, fault addr 0x1338520c in tid 16280 (.pl/...), pid 16010 ()
2020-03-12 12:07:09.051 16283-16283/? A/DEBUG: *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
2020-03-12 12:07:09.051 16283-16283/? A/DEBUG: Build fingerprint: 'samsung/j5y17ltexx/j5y17lte:8.1.0/M1AJQ/J530FXXU3BRJ2:user/release-keys'
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG: Revision: '7'
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG: ABI: 'arm'
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG: pid: 16010, tid: 16280, name: .pl/...  >>> com.erfg.music <<<
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG: signal 7 (SIGBUS), code 1 (BUS_ADRALN), fault addr 0x1338520c
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG:     r0 1338520c  r1 0000000c  r2 ca9e95cc  r3 0000000c
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG:     r4 6f31be58  r5 00000004  r6 00000000  r7 ca9e98c8
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG:     r8 00000000  r9 cb5f2c00  sl ca9e96c8  fp ca9e9654
2020-03-12 12:07:09.052 16283-16283/? A/DEBUG:     ip eae9fced  sp ca9e95a8  lr eae9fcf7  pc eae9fcfa  cpsr 600d0030
2020-03-12 12:07:09.185 16283-16283/? A/DEBUG: backtrace:
2020-03-12 12:07:09.185 16283-16283/? A/DEBUG:     #00 pc 00310cfa  /system/lib/libart.so (art::Unsafe_getLong(_JNIEnv*, _jobject*, _jobject*, long long)+13)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #01 pc 005db08f  /system/framework/arm/boot.oat (offset 0x1cb000) (sun.misc.Unsafe.getLong [DEDUPED]+110)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #02 pc 0040c575  /system/lib/libart.so (art_quick_invoke_stub_internal+68)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #03 pc 004116e5  /system/lib/libart.so (art_quick_invoke_stub+228)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #04 pc 000b0227  /system/lib/libart.so (art::ArtMethod::Invoke(art::Thread*, unsigned int*, unsigned int, art::JValue*, char const*)+138)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #05 pc 00204005  /system/lib/libart.so (art::interpreter::ArtInterpreterToCompiledCodeBridge(art::Thread*, art::ArtMethod*, art::ShadowFrame*, unsigned short, art::JValue*)+224)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #06 pc 001ff54d  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+588)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #07 pc 003f8c87  /system/lib/libart.so (MterpInvokeVirtualQuick+598)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #08 pc 00402714  /system/lib/libart.so (ExecuteMterpImpl+29972)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #09 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #10 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #11 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #12 pc 003f8c87  /system/lib/libart.so (MterpInvokeVirtualQuick+598)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #13 pc 00402714  /system/lib/libart.so (ExecuteMterpImpl+29972)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #14 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #15 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #16 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #17 pc 003f8c87  /system/lib/libart.so (MterpInvokeVirtualQuick+598)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #18 pc 00402714  /system/lib/libart.so (ExecuteMterpImpl+29972)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #19 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #20 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #21 pc 00200159  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb1ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+444)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #22 pc 003f8fa5  /system/lib/libart.so (MterpInvokeVirtualQuickRange+472)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #23 pc 00402794  /system/lib/libart.so (ExecuteMterpImpl+30100)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #24 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #25 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #26 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #27 pc 003f8c87  /system/lib/libart.so (MterpInvokeVirtualQuick+598)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #28 pc 00402714  /system/lib/libart.so (ExecuteMterpImpl+29972)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #29 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.186 16283-16283/? A/DEBUG:     #30 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #31 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #32 pc 003f77b9  /system/lib/libart.so (MterpInvokeStatic+184)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #33 pc 003feb14  /system/lib/libart.so (ExecuteMterpImpl+14612)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #34 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #35 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #36 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #37 pc 003f8c87  /system/lib/libart.so (MterpInvokeVirtualQuick+598)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #38 pc 00402714  /system/lib/libart.so (ExecuteMterpImpl+29972)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #39 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #40 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #41 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #42 pc 003f8c87  /system/lib/libart.so (MterpInvokeVirtualQuick+598)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #43 pc 00402714  /system/lib/libart.so (ExecuteMterpImpl+29972)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #44 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #45 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #46 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #47 pc 003f7391  /system/lib/libart.so (MterpInvokeInterface+1080)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #48 pc 003feb94  /system/lib/libart.so (ExecuteMterpImpl+14740)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #49 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #50 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #51 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #52 pc 003f7391  /system/lib/libart.so (MterpInvokeInterface+1080)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #53 pc 003feb94  /system/lib/libart.so (ExecuteMterpImpl+14740)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #54 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #55 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.187 16283-16283/? A/DEBUG:     #56 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #57 pc 003f7391  /system/lib/libart.so (MterpInvokeInterface+1080)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #58 pc 003feb94  /system/lib/libart.so (ExecuteMterpImpl+14740)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #59 pc 001e6bc1  /system/lib/libart.so (art::interpreter::Execute(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame&, art::JValue, bool)+340)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #60 pc 001eb36f  /system/lib/libart.so (art::interpreter::ArtInterpreterToInterpreterBridge(art::Thread*, art::DexFile::CodeItem const*, art::ShadowFrame*, art::JValue*)+142)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #61 pc 001ff535  /system/lib/libart.so (_ZN3art11interpreter6DoCallILb0ELb0EEEbPNS_9ArtMethodEPNS_6ThreadERNS_11ShadowFrameEPKNS_11InstructionEtPNS_6JValueE+564)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #62 pc 003f7391  /system/lib/libart.so (MterpInvokeInterface+1080)
2020-03-12 12:07:09.188 16283-16283/? A/DEBUG:     #63 pc 003feb94  /system/lib/libart.so (ExecuteMterpImpl+14740)
2020-03-12 12:07:11.258 2748-2748/? E//system/bin/tombstoned: Tombstone written to: /data/tombstones/tombstone_07
2020-03-12 12:07:11.266 2693-2693/? E/audit: type=1701 audit(1584011231.251:1220): auid=4294967295 uid=10219 gid=10219 ses=4294967295 subj=u:r:untrusted_app:s0:c512,c768 pid=16280 comm=".pl/..." exe="/system/bin/app_process32" sig=7
2020-03-12 12:07:11.301 2962-16284/? E/ActivityManager: Found activity ActivityRecord{dc4c01c u0 com.efgd.music/.MainActivity t-1 f} in proc activity list using null instead of expected ProcessRecord{ca03534 16010:com.efgd.music/u0a219}
2020-03-12 12:07:11.398 3338-3338/? E/SKBD: bbw getInstance start
2020-03-12 12:07:11.398 3338-3338/? E/SKBD: bbw sendSIPInformation state: 6   isAbstractKeyboardView :  true
2020-03-12 12:07:11.404 3338-16293/? E/SKBD: bbw sending null keyboardInfo as SIP is closed
2020-03-12 12:07:11.419 5224-5254/? E/PBSessionCacheImpl: sessionId[22976978907188413] not persisted.

Hello.

I'm trying to understand the design decision behind requiring hashing to be stateless.

Each call to hashByte/hashLong etc. starts with the state equal to the original seed and calls finalize at the end. As far as I can tell, this means that you can't chain these hash calls (like you can with Guava, for example) unless you keep passing finalized() hashes around.

Am I missing something? It seems like we should require the user to call finalize and to have a stateful long hash variable that can be reset() in each implementation. This allows the user to replicate the current behavior by calling reset()-hashByte()-finalize() but also to chain calls to each of the hash functions (reset()-hashByte()-hashLong()...finalize()).