diff --git a/CHANGES.txt b/CHANGES.txt
index beb878a02a..44c9787c12 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,4 +1,5 @@
 4.0-beta4
+ * Update jctools dependency to 3.1.0 (CASSANDRA-16255)
  * 'SSLEngine closed already' exception on failed outbound connection (CASSANDRA-16277)
  * Drain and/or shutdown might throw because of slow messaging service shutdown (CASSANDRA-16276)
  * Upgrade JNA to 5.6.0, dropping support for <=glibc-2.6 systems (CASSANDRA-16212)
diff --git a/build.xml b/build.xml
index 55c043f51f..7b17409ed9 100644
--- a/build.xml
+++ b/build.xml
@@ -665,7 +665,7 @@
           <dependency groupId="com.github.rholder" artifactId="snowball-stemmer" version="1.3.0.581.1" />
           <dependency groupId="com.googlecode.concurrent-trees" artifactId="concurrent-trees" version="2.4.0" />
           <dependency groupId="com.github.ben-manes.caffeine" artifactId="caffeine" version="2.3.5" />
-          <dependency groupId="org.jctools" artifactId="jctools-core" version="1.2.1"/>
+          <dependency groupId="org.jctools" artifactId="jctools-core" version="3.1.0"/>
           <dependency groupId="org.ow2.asm" artifactId="asm" version="${asm.version}" />
           <dependency groupId="org.ow2.asm" artifactId="asm-tree" version="${asm.version}" />
           <dependency groupId="org.ow2.asm" artifactId="asm-commons" version="${asm.version}" />
diff --git a/ide/nbproject/project.xml b/ide/nbproject/project.xml
index 505a5476ab..23427ee5b3 100644
--- a/ide/nbproject/project.xml
+++ b/ide/nbproject/project.xml
@@ -7,7 +7,7 @@
             <properties>
                 <property name="project.dir">..</property>
                 <!-- the compile classpaths should be distinct per compilation unit… but it is kept simple and the build will catch errors -->
-                <property name="cassandra.classpath.jars">${project.dir}/lib/HdrHistogram-2.1.9.jar:${project.dir}/lib/ST4-4.0.8.jar:${project.dir}/lib/airline-0.8.jar:${project.dir}/lib/antlr-runtime-3.5.2.jar:${project.dir}/lib/asm-7.1.jar:${project.dir}/lib/caffeine-2.3.5.jar:${project.dir}/lib/cassandra-driver-core-3.9.0-shaded.jar:${project.dir}/lib/chronicle-bytes-1.16.3.jar:${project.dir}/lib/chronicle-core-1.16.4.jar:${project.dir}/lib/chronicle-queue-4.16.3.jar:${project.dir}/lib/chronicle-threads-1.16.0.jar:${project.dir}/lib/chronicle-wire-1.16.1.jar:${project.dir}/lib/commons-cli-1.1.jar:${project.dir}/lib/commons-codec-1.9.jar:${project.dir}/lib/commons-lang3-3.11.jar:${project.dir}/lib/commons-math3-3.2.jar:${project.dir}/lib/concurrent-trees-2.4.0.jar:${project.dir}/lib/ecj-4.6.1.jar:${project.dir}/lib/guava-27.0-jre.jar:${project.dir}/lib/high-scale-lib-1.0.6.jar:${project.dir}/lib/hppc-0.8.1.jar:${project.dir}/lib/j2objc-annotations-1.3.jar:${project.dir}/lib/jackson-annotations-2.9.10.jar:${project.dir}/lib/jackson-core-2.9.10.jar:${project.dir}/lib/jackson-databind-2.9.10.4.jar:${project.dir}/lib/jamm-0.3.2.jar:${project.dir}/lib/javax.inject.jar:${project.dir}/lib/jbcrypt-0.3m.jar:${project.dir}/lib/jcl-over-slf4j-1.7.25.jar:${project.dir}/lib/jcommander-1.30.jar:${project.dir}/lib/jctools-core-1.2.1.jar:${project.dir}/lib/jflex-1.6.0.jar:${project.dir}/lib/jna-5.6.0.jar:${project.dir}/lib/json-simple-1.1.jar:${project.dir}/lib/jstackjunit-0.0.1.jar:${project.dir}/lib/jvm-attach-api-1.5.jar:${project.dir}/lib/log4j-over-slf4j-1.7.25.jar:${project.dir}/lib/logback-classic-1.2.3.jar:${project.dir}/lib/logback-core-1.2.3.jar:${project.dir}/lib/lz4-java-1.7.1.jar:${project.dir}/lib/metrics-core-3.1.5.jar:${project.dir}/lib/metrics-jvm-3.1.5.jar:${project.dir}/lib/metrics-logback-3.1.5.jar:${project.dir}/lib/mxdump-0.14.jar:${project.dir}/lib/netty-all-4.1.54.Final.jar:${project.dir}/lib/netty-tcnative-boringssl-static-2.0.34.Final.jar:${project.dir}/lib/ohc-core-0.5.1.jar:${project.dir}/lib/ohc-core-j8-0.5.1.jar:${project.dir}/lib/psjava-0.1.19.jar:${project.dir}/lib/reporter-config-base-3.0.3.jar:${project.dir}/lib/reporter-config3-3.0.3.jar:${project.dir}/lib/sigar-1.6.4.jar:${project.dir}/lib/sjk-cli-0.14.jar:${project.dir}/lib/sjk-core-0.14.jar:${project.dir}/lib/sjk-json-0.14.jar:${project.dir}/lib/sjk-stacktrace-0.14.jar:${project.dir}/lib/slf4j-api-1.7.25.jar:${project.dir}/lib/snakeyaml-1.26.jar:${project.dir}/lib/snappy-java-1.1.2.6.jar:${project.dir}/lib/snowball-stemmer-1.3.0.581.1.jar:${project.dir}/lib/stream-2.5.2.jar:${project.dir}/lib/zstd-jni-1.3.8-5.jar:${project.dir}/build/lib/jars/ST4-4.0.8.jar:${project.dir}/build/lib/jars/animal-sniffer-annotations-1.14.jar:${project.dir}/build/lib/jars/ant-1.9.7.jar:${project.dir}/build/lib/jars/ant-junit-1.9.7.jar:${project.dir}/build/lib/jars/ant-launcher-1.9.7.jar:${project.dir}/build/lib/jars/antlr-3.5.2.jar:${project.dir}/build/lib/jars/antlr-runtime-3.5.2.jar:${project.dir}/build/lib/jars/apache-rat-0.10.jar:${project.dir}/build/lib/jars/apache-rat-core-0.10.jar:${project.dir}/build/lib/jars/apache-rat-tasks-0.10.jar:${project.dir}/build/lib/jars/assertj-core-3.15.0.jar:${project.dir}/build/lib/jars/awaitility-4.0.3.jar:${project.dir}/build/lib/jars/byte-buddy-1.10.5.jar:${project.dir}/build/lib/jars/byte-buddy-agent-1.10.5.jar:${project.dir}/build/lib/jars/byteman-4.0.6.jar:${project.dir}/build/lib/jars/byteman-bmunit-4.0.6.jar:${project.dir}/build/lib/jars/byteman-install-4.0.6.jar:${project.dir}/build/lib/jars/byteman-submit-4.0.6.jar:${project.dir}/build/lib/jars/cassandra-driver-core-3.9.0-shaded.jar:${project.dir}/build/lib/jars/checker-qual-2.0.0.jar:${project.dir}/build/lib/jars/commons-beanutils-1.7.0.jar:${project.dir}/build/lib/jars/commons-beanutils-core-1.8.0.jar:${project.dir}/build/lib/jars/commons-cli-1.2.jar:${project.dir}/build/lib/jars/commons-codec-1.4.jar:${project.dir}/build/lib/jars/commons-collections-3.2.1.jar:${project.dir}/build/lib/jars/commons-compress-1.5.jar:${project.dir}/build/lib/jars/commons-configuration-1.6.jar:${project.dir}/build/lib/jars/commons-digester-1.8.jar:${project.dir}/build/lib/jars/commons-el-1.0.jar:${project.dir}/build/lib/jars/commons-httpclient-3.0.1.jar:${project.dir}/build/lib/jars/commons-io-2.2.jar:${project.dir}/build/lib/jars/commons-lang-2.4.jar:${project.dir}/build/lib/jars/commons-math-2.1.jar:${project.dir}/build/lib/jars/commons-math3-3.2.jar:${project.dir}/build/lib/jars/commons-net-1.4.1.jar:${project.dir}/build/lib/jars/compile-command-annotations-1.2.0.jar:${project.dir}/build/lib/jars/dtest-api-0.0.6.jar:${project.dir}/build/lib/jars/ecj-4.6.1.jar:${project.dir}/build/lib/jars/error_prone_annotations-2.0.18.jar:${project.dir}/build/lib/jars/ftplet-api-1.0.0.jar:${project.dir}/build/lib/jars/ftpserver-core-1.0.0.jar:${project.dir}/build/lib/jars/ftpserver-deprecated-1.0.0-M2.jar:${project.dir}/build/lib/jars/guava-23.5-android.jar:${project.dir}/build/lib/jars/hadoop-core-1.0.3.jar:${project.dir}/build/lib/jars/hadoop-minicluster-1.0.3.jar:${project.dir}/build/lib/jars/hadoop-test-1.0.3.jar:${project.dir}/build/lib/jars/hamcrest-2.1.jar:${project.dir}/build/lib/jars/hamcrest-core-1.3.jar:${project.dir}/build/lib/jars/hsqldb-1.8.0.10.jar:${project.dir}/build/lib/jars/j2objc-annotations-1.1.jar:${project.dir}/build/lib/jars/jackson-annotations-2.7.0.jar:${project.dir}/build/lib/jars/jackson-core-2.7.9.jar:${project.dir}/build/lib/jars/jackson-core-asl-1.0.1.jar:${project.dir}/build/lib/jars/jackson-databind-2.7.9.3.jar:${project.dir}/build/lib/jars/jackson-mapper-asl-1.0.1.jar:${project.dir}/build/lib/jars/jacocoagent.jar:${project.dir}/build/lib/jars/jasper-compiler-5.5.12.jar:${project.dir}/build/lib/jars/jasper-runtime-5.5.12.jar:${project.dir}/build/lib/jars/java-allocation-instrumenter-3.1.0.jar:${project.dir}/build/lib/jars/javassist-3.26.0-GA.jar:${project.dir}/build/lib/jars/jcommander-1.30.jar:${project.dir}/build/lib/jars/jersey-core-1.0.jar:${project.dir}/build/lib/jars/jersey-server-1.0.jar:${project.dir}/build/lib/jars/jets3t-0.7.1.jar:${project.dir}/build/lib/jars/jetty-6.1.26.jar:${project.dir}/build/lib/jars/jetty-util-6.1.26.jar:${project.dir}/build/lib/jars/jffi-1.2.16-native.jar:${project.dir}/build/lib/jars/jffi-1.2.16.jar:${project.dir}/build/lib/jars/jmh-core-1.21.jar:${project.dir}/build/lib/jars/jmh-generator-annprocess-1.21.jar:${project.dir}/build/lib/jars/jna-4.1.0.jar:${project.dir}/build/lib/jars/jnr-constants-0.9.9.jar:${project.dir}/build/lib/jars/jnr-ffi-2.1.7.jar:${project.dir}/build/lib/jars/jnr-posix-3.0.44.jar:${project.dir}/build/lib/jars/jnr-x86asm-1.0.2.jar:${project.dir}/build/lib/jars/jopt-simple-4.6.jar:${project.dir}/build/lib/jars/jsp-2.1-6.1.14.jar:${project.dir}/build/lib/jars/jsp-api-2.1-6.1.14.jar:${project.dir}/build/lib/jars/jsr305-2.0.2.jar:${project.dir}/build/lib/jars/jsr311-api-1.0.jar:${project.dir}/build/lib/jars/junit-4.12.jar:${project.dir}/build/lib/jars/jvm-attach-api-1.5.jar:${project.dir}/build/lib/jars/kfs-0.3.jar:${project.dir}/build/lib/jars/metrics-core-3.2.2.jar:${project.dir}/build/lib/jars/mina-core-2.0.0-M5.jar:${project.dir}/build/lib/jars/mockito-core-3.2.4.jar:${project.dir}/build/lib/jars/mxdump-0.14.jar:${project.dir}/build/lib/jars/objenesis-2.6.jar:${project.dir}/build/lib/jars/ohc-core-0.5.1.jar:${project.dir}/build/lib/jars/ohc-core-j8-0.5.1.jar:${project.dir}/build/lib/jars/org.jacoco.agent-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/org.jacoco.ant-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/org.jacoco.core-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/org.jacoco.report-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/oro-2.0.8.jar:${project.dir}/build/lib/jars/psjava-0.1.19.jar:${project.dir}/build/lib/jars/quicktheories-0.25.jar:${project.dir}/build/lib/jars/reflections-0.9.12.jar:${project.dir}/build/lib/jars/servlet-api-2.5-6.1.14.jar:${project.dir}/build/lib/jars/sjk-cli-0.14.jar:${project.dir}/build/lib/jars/sjk-core-0.14.jar:${project.dir}/build/lib/jars/sjk-hflame-0.14.jar:${project.dir}/build/lib/jars/sjk-jfr-standalone-0.7.jar:${project.dir}/build/lib/jars/sjk-jfr5-0.5.jar:${project.dir}/build/lib/jars/sjk-jfr6-0.7.jar:${project.dir}/build/lib/jars/sjk-json-0.14.jar:${project.dir}/build/lib/jars/sjk-nps-0.5.jar:${project.dir}/build/lib/jars/sjk-stacktrace-0.14.jar:${project.dir}/build/lib/jars/slf4j-api-1.7.25.jar:${project.dir}/build/lib/jars/xmlenc-0.52.jar:</property>
+                <property name="cassandra.classpath.jars">${project.dir}/lib/HdrHistogram-2.1.9.jar:${project.dir}/lib/ST4-4.0.8.jar:${project.dir}/lib/airline-0.8.jar:${project.dir}/lib/antlr-runtime-3.5.2.jar:${project.dir}/lib/asm-7.1.jar:${project.dir}/lib/caffeine-2.3.5.jar:${project.dir}/lib/cassandra-driver-core-3.9.0-shaded.jar:${project.dir}/lib/chronicle-bytes-1.16.3.jar:${project.dir}/lib/chronicle-core-1.16.4.jar:${project.dir}/lib/chronicle-queue-4.16.3.jar:${project.dir}/lib/chronicle-threads-1.16.0.jar:${project.dir}/lib/chronicle-wire-1.16.1.jar:${project.dir}/lib/commons-cli-1.1.jar:${project.dir}/lib/commons-codec-1.9.jar:${project.dir}/lib/commons-lang3-3.11.jar:${project.dir}/lib/commons-math3-3.2.jar:${project.dir}/lib/concurrent-trees-2.4.0.jar:${project.dir}/lib/ecj-4.6.1.jar:${project.dir}/lib/guava-27.0-jre.jar:${project.dir}/lib/high-scale-lib-1.0.6.jar:${project.dir}/lib/hppc-0.8.1.jar:${project.dir}/lib/j2objc-annotations-1.3.jar:${project.dir}/lib/jackson-annotations-2.9.10.jar:${project.dir}/lib/jackson-core-2.9.10.jar:${project.dir}/lib/jackson-databind-2.9.10.4.jar:${project.dir}/lib/jamm-0.3.2.jar:${project.dir}/lib/javax.inject.jar:${project.dir}/lib/jbcrypt-0.3m.jar:${project.dir}/lib/jcl-over-slf4j-1.7.25.jar:${project.dir}/lib/jcommander-1.30.jar:${project.dir}/lib/jctools-core-3.1.0.jar:${project.dir}/lib/jflex-1.6.0.jar:${project.dir}/lib/jna-5.6.0.jar:${project.dir}/lib/json-simple-1.1.jar:${project.dir}/lib/jstackjunit-0.0.1.jar:${project.dir}/lib/jvm-attach-api-1.5.jar:${project.dir}/lib/log4j-over-slf4j-1.7.25.jar:${project.dir}/lib/logback-classic-1.2.3.jar:${project.dir}/lib/logback-core-1.2.3.jar:${project.dir}/lib/lz4-java-1.7.1.jar:${project.dir}/lib/metrics-core-3.1.5.jar:${project.dir}/lib/metrics-jvm-3.1.5.jar:${project.dir}/lib/metrics-logback-3.1.5.jar:${project.dir}/lib/mxdump-0.14.jar:${project.dir}/lib/netty-all-4.1.54.Final.jar:${project.dir}/lib/netty-tcnative-boringssl-static-2.0.34.Final.jar:${project.dir}/lib/ohc-core-0.5.1.jar:${project.dir}/lib/ohc-core-j8-0.5.1.jar:${project.dir}/lib/psjava-0.1.19.jar:${project.dir}/lib/reporter-config-base-3.0.3.jar:${project.dir}/lib/reporter-config3-3.0.3.jar:${project.dir}/lib/sigar-1.6.4.jar:${project.dir}/lib/sjk-cli-0.14.jar:${project.dir}/lib/sjk-core-0.14.jar:${project.dir}/lib/sjk-json-0.14.jar:${project.dir}/lib/sjk-stacktrace-0.14.jar:${project.dir}/lib/slf4j-api-1.7.25.jar:${project.dir}/lib/snakeyaml-1.26.jar:${project.dir}/lib/snappy-java-1.1.2.6.jar:${project.dir}/lib/snowball-stemmer-1.3.0.581.1.jar:${project.dir}/lib/stream-2.5.2.jar:${project.dir}/lib/zstd-jni-1.3.8-5.jar:${project.dir}/build/lib/jars/ST4-4.0.8.jar:${project.dir}/build/lib/jars/animal-sniffer-annotations-1.14.jar:${project.dir}/build/lib/jars/ant-1.9.7.jar:${project.dir}/build/lib/jars/ant-junit-1.9.7.jar:${project.dir}/build/lib/jars/ant-launcher-1.9.7.jar:${project.dir}/build/lib/jars/antlr-3.5.2.jar:${project.dir}/build/lib/jars/antlr-runtime-3.5.2.jar:${project.dir}/build/lib/jars/apache-rat-0.10.jar:${project.dir}/build/lib/jars/apache-rat-core-0.10.jar:${project.dir}/build/lib/jars/apache-rat-tasks-0.10.jar:${project.dir}/build/lib/jars/assertj-core-3.15.0.jar:${project.dir}/build/lib/jars/awaitility-4.0.3.jar:${project.dir}/build/lib/jars/byte-buddy-1.10.5.jar:${project.dir}/build/lib/jars/byte-buddy-agent-1.10.5.jar:${project.dir}/build/lib/jars/byteman-4.0.6.jar:${project.dir}/build/lib/jars/byteman-bmunit-4.0.6.jar:${project.dir}/build/lib/jars/byteman-install-4.0.6.jar:${project.dir}/build/lib/jars/byteman-submit-4.0.6.jar:${project.dir}/build/lib/jars/cassandra-driver-core-3.9.0-shaded.jar:${project.dir}/build/lib/jars/checker-qual-2.0.0.jar:${project.dir}/build/lib/jars/commons-beanutils-1.7.0.jar:${project.dir}/build/lib/jars/commons-beanutils-core-1.8.0.jar:${project.dir}/build/lib/jars/commons-cli-1.2.jar:${project.dir}/build/lib/jars/commons-codec-1.4.jar:${project.dir}/build/lib/jars/commons-collections-3.2.1.jar:${project.dir}/build/lib/jars/commons-compress-1.5.jar:${project.dir}/build/lib/jars/commons-configuration-1.6.jar:${project.dir}/build/lib/jars/commons-digester-1.8.jar:${project.dir}/build/lib/jars/commons-el-1.0.jar:${project.dir}/build/lib/jars/commons-httpclient-3.0.1.jar:${project.dir}/build/lib/jars/commons-io-2.2.jar:${project.dir}/build/lib/jars/commons-lang-2.4.jar:${project.dir}/build/lib/jars/commons-math-2.1.jar:${project.dir}/build/lib/jars/commons-math3-3.2.jar:${project.dir}/build/lib/jars/commons-net-1.4.1.jar:${project.dir}/build/lib/jars/compile-command-annotations-1.2.0.jar:${project.dir}/build/lib/jars/dtest-api-0.0.6.jar:${project.dir}/build/lib/jars/ecj-4.6.1.jar:${project.dir}/build/lib/jars/error_prone_annotations-2.0.18.jar:${project.dir}/build/lib/jars/ftplet-api-1.0.0.jar:${project.dir}/build/lib/jars/ftpserver-core-1.0.0.jar:${project.dir}/build/lib/jars/ftpserver-deprecated-1.0.0-M2.jar:${project.dir}/build/lib/jars/guava-23.5-android.jar:${project.dir}/build/lib/jars/hadoop-core-1.0.3.jar:${project.dir}/build/lib/jars/hadoop-minicluster-1.0.3.jar:${project.dir}/build/lib/jars/hadoop-test-1.0.3.jar:${project.dir}/build/lib/jars/hamcrest-2.1.jar:${project.dir}/build/lib/jars/hamcrest-core-1.3.jar:${project.dir}/build/lib/jars/hsqldb-1.8.0.10.jar:${project.dir}/build/lib/jars/j2objc-annotations-1.1.jar:${project.dir}/build/lib/jars/jackson-annotations-2.7.0.jar:${project.dir}/build/lib/jars/jackson-core-2.7.9.jar:${project.dir}/build/lib/jars/jackson-core-asl-1.0.1.jar:${project.dir}/build/lib/jars/jackson-databind-2.7.9.3.jar:${project.dir}/build/lib/jars/jackson-mapper-asl-1.0.1.jar:${project.dir}/build/lib/jars/jacocoagent.jar:${project.dir}/build/lib/jars/jasper-compiler-5.5.12.jar:${project.dir}/build/lib/jars/jasper-runtime-5.5.12.jar:${project.dir}/build/lib/jars/java-allocation-instrumenter-3.1.0.jar:${project.dir}/build/lib/jars/javassist-3.26.0-GA.jar:${project.dir}/build/lib/jars/jcommander-1.30.jar:${project.dir}/build/lib/jars/jersey-core-1.0.jar:${project.dir}/build/lib/jars/jersey-server-1.0.jar:${project.dir}/build/lib/jars/jets3t-0.7.1.jar:${project.dir}/build/lib/jars/jetty-6.1.26.jar:${project.dir}/build/lib/jars/jetty-util-6.1.26.jar:${project.dir}/build/lib/jars/jffi-1.2.16-native.jar:${project.dir}/build/lib/jars/jffi-1.2.16.jar:${project.dir}/build/lib/jars/jmh-core-1.21.jar:${project.dir}/build/lib/jars/jmh-generator-annprocess-1.21.jar:${project.dir}/build/lib/jars/jna-4.1.0.jar:${project.dir}/build/lib/jars/jnr-constants-0.9.9.jar:${project.dir}/build/lib/jars/jnr-ffi-2.1.7.jar:${project.dir}/build/lib/jars/jnr-posix-3.0.44.jar:${project.dir}/build/lib/jars/jnr-x86asm-1.0.2.jar:${project.dir}/build/lib/jars/jopt-simple-4.6.jar:${project.dir}/build/lib/jars/jsp-2.1-6.1.14.jar:${project.dir}/build/lib/jars/jsp-api-2.1-6.1.14.jar:${project.dir}/build/lib/jars/jsr305-2.0.2.jar:${project.dir}/build/lib/jars/jsr311-api-1.0.jar:${project.dir}/build/lib/jars/junit-4.12.jar:${project.dir}/build/lib/jars/jvm-attach-api-1.5.jar:${project.dir}/build/lib/jars/kfs-0.3.jar:${project.dir}/build/lib/jars/metrics-core-3.2.2.jar:${project.dir}/build/lib/jars/mina-core-2.0.0-M5.jar:${project.dir}/build/lib/jars/mockito-core-3.2.4.jar:${project.dir}/build/lib/jars/mxdump-0.14.jar:${project.dir}/build/lib/jars/objenesis-2.6.jar:${project.dir}/build/lib/jars/ohc-core-0.5.1.jar:${project.dir}/build/lib/jars/ohc-core-j8-0.5.1.jar:${project.dir}/build/lib/jars/org.jacoco.agent-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/org.jacoco.ant-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/org.jacoco.core-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/org.jacoco.report-0.7.5.201505241946.jar:${project.dir}/build/lib/jars/oro-2.0.8.jar:${project.dir}/build/lib/jars/psjava-0.1.19.jar:${project.dir}/build/lib/jars/quicktheories-0.25.jar:${project.dir}/build/lib/jars/reflections-0.9.12.jar:${project.dir}/build/lib/jars/servlet-api-2.5-6.1.14.jar:${project.dir}/build/lib/jars/sjk-cli-0.14.jar:${project.dir}/build/lib/jars/sjk-core-0.14.jar:${project.dir}/build/lib/jars/sjk-hflame-0.14.jar:${project.dir}/build/lib/jars/sjk-jfr-standalone-0.7.jar:${project.dir}/build/lib/jars/sjk-jfr5-0.5.jar:${project.dir}/build/lib/jars/sjk-jfr6-0.7.jar:${project.dir}/build/lib/jars/sjk-json-0.14.jar:${project.dir}/build/lib/jars/sjk-nps-0.5.jar:${project.dir}/build/lib/jars/sjk-stacktrace-0.14.jar:${project.dir}/build/lib/jars/slf4j-api-1.7.25.jar:${project.dir}/build/lib/jars/xmlenc-0.52.jar:</property>
             </properties>
             <folders>
                 <source-folder>
diff --git a/lib/jctools-core-1.2.1.jar b/lib/jctools-core-1.2.1.jar
deleted file mode 100644
index fa1137bb0d..0000000000
Binary files a/lib/jctools-core-1.2.1.jar and /dev/null differ
diff --git a/lib/jctools-core-3.1.0.jar b/lib/jctools-core-3.1.0.jar
new file mode 100644
index 0000000000..eb643442c6
Binary files /dev/null and b/lib/jctools-core-3.1.0.jar differ
diff --git a/lib/licenses/jctools-core-1.2.1.txt b/lib/licenses/jctools-core-3.1.0.txt
similarity index 99%
rename from lib/licenses/jctools-core-1.2.1.txt
rename to lib/licenses/jctools-core-3.1.0.txt
index d645695673..984f94429d 100644
--- a/lib/licenses/jctools-core-1.2.1.txt
+++ b/lib/licenses/jctools-core-3.1.0.txt
@@ -1,5 +1,4 @@
-
-                                 Apache License
+Apache License
                            Version 2.0, January 2004
                         http://www.apache.org/licenses/
 
@@ -179,7 +178,7 @@
    APPENDIX: How to apply the Apache License to your work.
 
       To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "[]"
+      boilerplate notice, with the fields enclosed by brackets "{}"
       replaced with your own identifying information. (Don't include
       the brackets!)  The text should be enclosed in the appropriate
       comment syntax for the file format. We also recommend that a
@@ -187,7 +186,7 @@
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright [yyyy] [name of copyright owner]
+   Copyright {yyyy} {name of copyright owner}
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
@@ -200,3 +199,5 @@
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
+
+