Add putIfAbsent optimistic fastpath (fixes #506)

Put optimistically reads the existing value to avoid a map lambda and
hash table lock. If absent, it then tries to add a new entry. If this
fails when racing with another writer, a putIfAbsent can validate and
return the existing value immediately. Previously it would do these
steps after acquiring the entry lock during the update code path.

This mirrors the fastpath when the entry was found and no update is
needed for a putIfAbsent. That case will be more common, this only
assists when populating, e.g. after expiration when many threads
may try to reload the value.

build.gradle

@@ -153,6 +153,12 @@ tasks.coveralls {
   onlyIf { System.env.'CI' && !JavaVersion.current().isJava9Compatible() }
 }
 
-dependencyUpdates.resolutionStrategy {
-  force testLibraries.truth
+def isNonStable = { String version ->
+  def stableKeyword = ['RELEASE', 'FINAL', 'GA'].any { it -> version.toUpperCase().contains(it) }
+  def regex = /^[0-9,.v-]+(-r)?$/
+  return !stableKeyword && !(version ==~ regex)
+}
+
+dependencyUpdates.rejectVersionIf {
+  it.candidate.group == 'org.slf4j' && isNonStable(it.candidate.version)
 }

caffeine/build.gradle

@@ -66,10 +66,6 @@ dependencies {
   javaPoetImplementation libraries.googleJavaFormat
 }
 
-java {
-  withSourcesJar()
-}
-
 compileCodeGenJava {
   gradle.taskGraph.whenReady {
     enabled = gradle.taskGraph.hasTask('uploadArchives')

caffeine/src/main/java/com/github/benmanes/caffeine/cache/BoundedLocalCache.java

@@ -2086,6 +2086,17 @@ public Map<K, V> getAllPresent(Iterable<? extends K> keys) {
         if (prior == null) {
           afterWrite(new AddTask(node, newWeight));
           return null;
+        } else if (onlyIfAbsent) {
+          // An optimistic fast path to avoid unnecessary locking
+          V currentValue = prior.getValue();
+          if ((currentValue != null) && !hasExpired(prior, now)) {
+            if (!isComputingAsync(prior)) {
+              tryExpireAfterRead(prior, key, currentValue, expiry(), now);
+              setAccessTime(prior, now);
+            }
+            afterRead(prior, now, /* recordHit */ false);
+            return currentValue;
+          }
         }
       } else if (onlyIfAbsent) {
         // An optimistic fast path to avoid unnecessary locking

checksum.xml

@@ -8,6 +8,7 @@
   <trusted-keys>
     <trusted-key id='36feecf06c2da10b' group='biz.aQute.bnd' />
     <trusted-key id='52e6585e0102b84d' group='biz.aQute.bnd' />
+    <trusted-key id='c5cc0278b1ee1c33' group='biz.aQute.bnd' />
     <trusted-key id='2189ca6247f3dee5' group='com.android.tools' />
     <trusted-key id='2189ca6247f3dee5' group='com.android.tools.build' />
     <trusted-key id='2189ca6247f3dee5' group='com.android.tools.ddms' />
@@ -45,6 +46,7 @@
     <trusted-key id='9a259c7ee636c5ed' group='com.google.googlejavaformat' />
     <trusted-key id='abe9f3126bb741c1' group='com.google.guava' />
     <trusted-key id='f6d4a1d411e9d1ae' group='com.google.guava' />
+    <trusted-key id='0a2496e4955cac56' group='com.google.inject' />
     <trusted-key id='f0df21d1d0a3c384' group='com.google.inject' />
     <trusted-key id='29579f18fa8fd93b' group='com.google.j2objc' />
     <trusted-key id='a7764f502a938c99' group='com.google.protobuf' />
@@ -139,6 +141,7 @@
     <trusted-key id='9ae296fd02e9f65b' group='org.apache.commons' />
     <trusted-key id='a2115ae15f6b8b72' group='org.apache.commons' />
     <trusted-key id='3fcf529ff2f27a06' group='org.apache.felix' />
+    <trusted-key id='8d37f2f060a1af50' group='org.apache.felix' />
     <trusted-key id='9054823a859a7237' group='org.apache.felix' />
     <trusted-key id='bff2ee42c8282e76' group='org.apache.felix' />
     <trusted-key id='de78987a9cd4d9d3' group='org.apache.htrace' />
@@ -216,9 +219,11 @@
     <trusted-key id='cfca4a29d26468de' group='org.sonarsource.scanner.api' />
     <trusted-key id='cfca4a29d26468de' group='org.sonarsource.scanner.gradle' />
     <trusted-key id='9440c8d6decafa12' group='org.testng' />
+    <trusted-key id='dddafa7674e54418' group='org.testng' />
     <trusted-key id='72385ff0af338d52' group='org.threeten' />
     <trusted-key id='38ee757d69184620' group='org.tukaani' />
     <trusted-key id='04633a577c200941' group='org.vafer' />
+    <trusted-key id='e0130a3ed5a2079e' group='org.webjars' />
     <trusted-key id='55c7e5e701832382' group='org.yaml' />
     <trusted-key id='e65e11d40d80db7c' group='site.ycsb' />
     <trusted-key id='a840320c83d56348' group='systems.comodal' />
@@ -301,6 +306,9 @@
     <dependency group='com.github.ben-manes' module='gradle-versions-plugin' version='0.36.0'>
       <sha512>D57AC7E2C3AB7135504C2ADED5E622032AB03905EF259645A0EE2B0D3B9868BC15131AD50027F47044F710DBA681AD2A54B669451C795E8189378AD2525D4E44</sha512>
     </dependency>
+    <dependency group='com.github.ben-manes' module='gradle-versions-plugin' version='0.38.0'>
+      <sha512>C1AB30AA9984AAF40E0DEF6474F535875ABCCA1568E6D495317D1092B782AC39D13505BBBD50877589610A59273AC89ADE0B68EEE0501961C1AF17CA5D509178</sha512>
+    </dependency>
     <dependency group='com.github.brianfrankcooper.YCSB' module='core' version='0.15.0'>
       <sha512>DF5BFED7DFC327166FE0CB81BD6A9655F44CCB268E7E69204BD09955147CE9A97EBBCC28F9ACF315DBAF49E850A43CE8744F44E68D7BE816EACCAF0BEE41B203</sha512>
     </dependency>
@@ -376,6 +384,9 @@
     <dependency group='gradle.plugin.com.github.spotbugs.snom' module='spotbugs-gradle-plugin' version='4.6.1'>
       <sha512>97823390838111768E99E68A9EB8E603E528A910850EF58B1A9198828C5DE9C8F4BE53238DBED56C46A2471E5F1871FA4CD1D34F86FA44B4E3643BD3D03901A9</sha512>
     </dependency>
+    <dependency group='gradle.plugin.com.github.spotbugs.snom' module='spotbugs-gradle-plugin' version='4.6.2'>
+      <sha512>A9789681117B1D01021884DB7D0F6367CA3B7F4AC6A4630BC6769DFDF6D1003E49CD7A894D803BFA6244AEE5135F610EEAA4E2E1AD67F8C5196C8B7A1CEEE451</sha512>
+    </dependency>
     <dependency group='gradle.plugin.com.github.spotbugs' module='spotbugs-gradle-plugin' version='2.0.0'>
       <sha512>B3BFAD07E6A3D4D73CBCE802D8614CF4AC84E589166D243D41028DC077F84C027DF4D514F145360405F37DA73A8F2E7B65D90877A9EE1151174D2440530F9051</sha512>
     </dependency>
@@ -460,6 +471,9 @@
     <dependency group='org.checkerframework' module='checkerframework-gradle-plugin' version='0.5.16'>
       <sha512>5A630269AE2E19E48529A5D768DD9C01DCC9A91247A9D24CC777F0D2B79DBA06AC40AEAC4560C57BFCB6BBBD423621313013B742B78C24C8861490C957A4DC92</sha512>
     </dependency>
+    <dependency group='org.checkerframework' module='checkerframework-gradle-plugin' version='0.5.17'>
+      <sha512>6B9620FFEA84B67D27132B6BD8D2EB080C519383CC3187474CABD10EB398BEB259D25974386508AADA1194A2BDAB5D223FAB584AC84E6B03D007EDEBFCBD9A68</sha512>
+    </dependency>
     <dependency group='org.codehaus.groovy.modules.http-builder' module='http-builder' version='0.7.1'>
       <sha512>BC7BC2A514F8CA104A392ECF8736F4A3D316EE988FA91299D33B0AF46134B38E14E4A5061449D17B2DF7A521643E6C02DFA37CC277ED7CAB7CE83C28C00E9719</sha512>
     </dependency>

gradle.properties

@@ -1,5 +1,6 @@
 org.gradle.jvmargs=-Xmx2g -XX:+UseG1GC -XX:SoftRefLRUPolicyMSPerMB=0 -noverify -XX:+HeapDumpOnOutOfMemoryError
 systemProp.org.gradle.internal.publish.checksums.insecure=true
+org.gradle.parallel=true
 org.gradle.daemon=true
 checksumIgnore=true
 nexusUsername=

gradle/dependencies.gradle

@@ -25,16 +25,16 @@
  */
 ext {
   versions = [
-    akka: '2.6.12',
+    akka: '2.6.13',
     cache2k: '2.1.1.Alpha',
-    checkerFramework: '3.10.0',
+    checkerFramework: '3.11.0',
     coherence: '20.06',
     commonsCompress: '1.20',
-    commonsLang3: '3.11',
+    commonsLang3: '3.12.0',
     commonsMath3: '3.6.1',
     concurrentlinkedhashmap: '1.4.2',
     config: '1.4.1',
-    ehcache3: '3.9.1',
+    ehcache3: '3.9.2',
     errorprone: '2.5.1',
     errorproneJavac: '9+181-r4173-1',
     elasticSearch: '7.11.1',
@@ -49,7 +49,7 @@ ext {
     javaObjectLayout: '0.14',
     javapoet: '1.13.0',
     jcache: '1.1.1',
-    jmh: '1.27',
+    jmh: '1.28',
     joor: '0.9.13',
     jsr330: '1',
     nullaway: '0.8.0',
@@ -62,43 +62,44 @@ ext {
     univocityParsers: '2.9.1',
     ycsb: '0.17.0',
     xz: '1.8',
-    zstd: '1.4.8-4',
+    zstd: '1.4.8-7',
   ]
   testVersions = [
     awaitility: '4.0.3',
     easymock: '4.2',
+    guice: '5.0.1',
     hamcrest: '2.2',
     jcacheTck: '1.1.1',
-    jctools: '3.2.0',
+    jctools: '3.3.0',
     junit: '4.13.2',
-    mockito: '3.7.7',
+    mockito: '3.8.0',
     paxExam: '4.13.4',
-    testng: '7.3.0',
-    truth: '0.24',
+    testng: '7.4.0',
+    truth: '1.1.2',
     felix: '7.0.0',
-    felixScr: '2.1.24',
+    felixScr: '2.1.26',
     osgiUtilFunction: '1.1.0',
     osgiUtilPromise: '1.1.1',
   ]
   pluginVersions = [
-    bnd: '5.2.0',
-    checkerFramework: '0.5.16',
-    checkstyle: '8.40',
+    bnd: '5.3.0',
+    checkerFramework: '0.5.17',
+    checkstyle: '8.41',
     coveralls: '2.8.4',
     errorprone: '1.3.0',
     jacoco: '0.8.6',
     jmh: '0.5.3',
     jmhReport: '0.9.0',
     nexusPublish: '1.0.0',
     nullaway: '1.0.2',
-    pmd: '6.31.0',
+    pmd: '6.32.0',
     semanticVersioning: '1.1.0',
     shadow: '6.1.0',
     sonarqube: '3.1.1',
-    spotbugs: '4.2.0',
-    spotbugsPlugin: '4.6.1',
+    spotbugs: '4.2.2',
+    spotbugsPlugin: '4.6.2',
     stats: '0.2.2',
-    versions: '0.36.0',
+    versions: '0.38.0',
   ]
   annotationProcessorVersions = [
     autoValue: '1.7.4',
@@ -181,7 +182,7 @@ ext {
         exclude group: 'junit'
         exclude group: 'guice'
       },
-      'com.google.inject:guice:4.2.3'
+      "com.google.inject:guice:${testVersions.guice}"
     ],
     truth: "com.google.truth:truth:${testVersions.truth}",
   ]

gradle/publish.gradle

@@ -73,9 +73,3 @@ signing {
   useInMemoryPgpKeys(signingKeyId, signingKey, signingPassword)
   sign publishing.publications.mavenJava
 }
-
-javadoc {
-  if (JavaVersion.current().isJava9Compatible()) {
-    options.addBooleanOption('html5', true)
-  }
-}

gradle/wrapper/gradle-wrapper.properties

@@ -1,4 +1,4 @@
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.8.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.8.3-bin.zip
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME