├── .github └── workflows │ └── build.yml ├── .gitignore ├── .mvn └── wrapper │ ├── MavenWrapperDownloader.java │ ├── maven-wrapper.jar │ └── maven-wrapper.properties ├── .sdkmanrc ├── README.md ├── img ├── Kernel Threads List.png ├── Kernel Threads Overview.png ├── Virtual Threads DefaultCarrierPool List.png ├── Virtual Threads DefaultCarrierPool Overview.png ├── Virtual Threads List.png └── Virtual Threads Overview.png ├── mvnw ├── mvnw.cmd ├── pom.xml └── src └── main ├── java └── com │ └── example │ └── loomservlet │ └── ServletOfTheLoomApplication.java └── resources └── application.properties /.github/workflows/build.yml: -------------------------------------------------------------------------------- 1 | name: Java CI 2 | 3 | on: 4 | push: 5 | branches: [main] 6 | pull_request: 7 | branches: [main] 8 | 9 | jobs: 10 | build: 11 | runs-on: ubuntu-latest 12 | name: Java + Loom early access build 13 | steps: 14 | - name: Checkout source code 15 | uses: actions/checkout@v3 16 | - name: setup 17 | uses: oracle-actions/setup-java@v1 18 | with: 19 | website: jdk.java.net 20 | release: 19 21 | - name: Build with Maven Wrapper 22 | run: ./mvnw clean verify 23 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | HELP.md 2 | target/ 3 | !.mvn/wrapper/maven-wrapper.jar 4 | !**/src/main/**/target/ 5 | !**/src/test/**/target/ 6 | 7 | ### STS ### 8 | .apt_generated 9 | .classpath 10 | .factorypath 11 | .project 12 | .settings 13 | .springBeans 14 | .sts4-cache 15 | 16 | ### IntelliJ IDEA ### 17 | .idea 18 | *.iws 19 | *.iml 20 | *.ipr 21 | 22 | ### NetBeans ### 23 | /nbproject/private/ 24 | /nbbuild/ 25 | /dist/ 26 | /nbdist/ 27 | /.nb-gradle/ 28 | build/ 29 | !**/src/main/**/build/ 30 | !**/src/test/**/build/ 31 | 32 | ### VS Code ### 33 | .vscode/ 34 | -------------------------------------------------------------------------------- /.mvn/wrapper/MavenWrapperDownloader.java: -------------------------------------------------------------------------------- 1 | /* 2 | * Copyright 2007-present the original author or authors. 3 | * 4 | * Licensed under the Apache License, Version 2.0 (the "License"); 5 | * you may not use this file except in compliance with the License. 6 | * You may obtain a copy of the License at 7 | * 8 | * https://www.apache.org/licenses/LICENSE-2.0 9 | * 10 | * Unless required by applicable law or agreed to in writing, software 11 | * distributed under the License is distributed on an "AS IS" BASIS, 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 | * See the License for the specific language governing permissions and 14 | * limitations under the License. 15 | */ 16 | 17 | import java.net.*; 18 | import java.io.*; 19 | import java.nio.channels.*; 20 | import java.util.Properties; 21 | 22 | public class MavenWrapperDownloader { 23 | 24 | private static final String WRAPPER_VERSION = "0.5.6"; 25 | /** 26 | * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided. 27 | */ 28 | private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/" 29 | + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar"; 30 | 31 | /** 32 | * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to 33 | * use instead of the default one. 34 | */ 35 | private static final String MAVEN_WRAPPER_PROPERTIES_PATH = 36 | ".mvn/wrapper/maven-wrapper.properties"; 37 | 38 | /** 39 | * Path where the maven-wrapper.jar will be saved to. 40 | */ 41 | private static final String MAVEN_WRAPPER_JAR_PATH = 42 | ".mvn/wrapper/maven-wrapper.jar"; 43 | 44 | /** 45 | * Name of the property which should be used to override the default download url for the wrapper. 46 | */ 47 | private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl"; 48 | 49 | public static void main(String args[]) { 50 | System.out.println("- Downloader started"); 51 | File baseDirectory = new File(args[0]); 52 | System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath()); 53 | 54 | // If the maven-wrapper.properties exists, read it and check if it contains a custom 55 | // wrapperUrl parameter. 56 | File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH); 57 | String url = DEFAULT_DOWNLOAD_URL; 58 | if (mavenWrapperPropertyFile.exists()) { 59 | FileInputStream mavenWrapperPropertyFileInputStream = null; 60 | try { 61 | mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile); 62 | Properties mavenWrapperProperties = new Properties(); 63 | mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream); 64 | url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url); 65 | } 66 | catch (IOException e) { 67 | System.out 68 | .println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'"); 69 | } 70 | finally { 71 | try { 72 | if (mavenWrapperPropertyFileInputStream != null) { 73 | mavenWrapperPropertyFileInputStream.close(); 74 | } 75 | } 76 | catch (IOException e) { 77 | // Ignore ... 78 | } 79 | } 80 | } 81 | System.out.println("- Downloading from: " + url); 82 | 83 | File outputFile = new File(baseDirectory 84 | .getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH); 85 | if (!outputFile.getParentFile().exists()) { 86 | if (!outputFile.getParentFile().mkdirs()) { 87 | System.out.println( 88 | "- ERROR creating output directory '" + outputFile.getParentFile() 89 | .getAbsolutePath() + "'"); 90 | } 91 | } 92 | System.out.println("- Downloading to: " + outputFile.getAbsolutePath()); 93 | try { 94 | downloadFileFromURL(url, outputFile); 95 | System.out.println("Done"); 96 | System.exit(0); 97 | } 98 | catch (Throwable e) { 99 | System.out.println("- Error downloading"); 100 | e.printStackTrace(); 101 | System.exit(1); 102 | } 103 | } 104 | 105 | private static void downloadFileFromURL(String urlString, File destination) throws Exception { 106 | if (System.getenv("MVNW_USERNAME") != null && System 107 | .getenv("MVNW_PASSWORD") != null) { 108 | String username = System.getenv("MVNW_USERNAME"); 109 | char[] password = System.getenv("MVNW_PASSWORD").toCharArray(); 110 | Authenticator.setDefault(new Authenticator() { 111 | @Override 112 | protected PasswordAuthentication getPasswordAuthentication() { 113 | return new PasswordAuthentication(username, password); 114 | } 115 | }); 116 | } 117 | URL website = new URL(urlString); 118 | ReadableByteChannel rbc; 119 | rbc = Channels.newChannel(website.openStream()); 120 | FileOutputStream fos = new FileOutputStream(destination); 121 | fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE); 122 | fos.close(); 123 | rbc.close(); 124 | } 125 | 126 | } 127 | -------------------------------------------------------------------------------- /.mvn/wrapper/maven-wrapper.jar: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/.mvn/wrapper/maven-wrapper.jar -------------------------------------------------------------------------------- /.mvn/wrapper/maven-wrapper.properties: -------------------------------------------------------------------------------- 1 | distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip 2 | wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar 3 | -------------------------------------------------------------------------------- /.sdkmanrc: -------------------------------------------------------------------------------- 1 | java=19.ea.32-open 2 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | Project Loom Experiment using Spring Boot, Spring WebMVC, and Postgres 2 | ====================================================================== 3 | 4 | This repository contains an experiment that uses a Spring Boot application with [Virtual Threads](https://wiki.openjdk.java.net/display/loom/Main). 5 | 6 | Involved components: 7 | 8 | * Spring Framework 6.0 M5 9 | * Spring Boot 3.0 M4 10 | * Apache Tomcat 10.1.0 M17 11 | * HikariCP 5.0.1 (Loom issue: https://github.com/brettwooldridge/HikariCP/issues/1463) 12 | * PGJDBC 42.4.0 (PR that turns `synchronized` into Loom-friendly Locks: https://github.com/pgjdbc/pgjdbc/issues/1951) 13 | 14 | This experiment evolves incrementally, find the previous state at https://github.com/mp911de/spring-boot-virtual-threads-experiment/tree/boot-2.4. 15 | 16 | You need Java 19 (EAP) with `--enable-preview` to run the example. 17 | 18 | Customization of a vanilla Spring Boot with Tomcat application: 19 | 20 | ```java 21 | @Bean 22 | AsyncTaskExecutor applicationTaskExecutor() { 23 | // enable async servlet support 24 | ExecutorService executorService = Executors.newVirtualThreadPerTaskExecutor(); 25 | return new TaskExecutorAdapter(executorService::execute); 26 | } 27 | 28 | @Bean 29 | TomcatProtocolHandlerCustomizer protocolHandlerVirtualThreadExecutorCustomizer() { 30 | 31 | return protocolHandler -> { 32 | protocolHandler.setExecutor(Executors.newVirtualThreadPerTaskExecutor()); 33 | }; 34 | } 35 | ``` 36 | 37 | After starting the application, run `GET http://localhpst:8080/where-am-i` to verify you're running on a virtual thread: 38 | 39 | ``` 40 | $ http :8080/where-am-i 41 | HTTP/1.1 200 42 | Connection: keep-alive 43 | Content-Length: 51 44 | Content-Type: text/plain;charset=UTF-8 45 | Date: Wed, 27 Jul 2022 09:34:23 GMT 46 | Keep-Alive: timeout=60 47 | 48 | VirtualThread[#82]/runnable@ForkJoinPool-1-worker-1 49 | ``` 50 | 51 | License 52 | ------- 53 | 54 | * [Apache License 2.0](https://www.apache.org/licenses/LICENSE-2.0) 55 | -------------------------------------------------------------------------------- /img/Kernel Threads List.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/img/Kernel Threads List.png -------------------------------------------------------------------------------- /img/Kernel Threads Overview.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/img/Kernel Threads Overview.png -------------------------------------------------------------------------------- /img/Virtual Threads DefaultCarrierPool List.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/img/Virtual Threads DefaultCarrierPool List.png -------------------------------------------------------------------------------- /img/Virtual Threads DefaultCarrierPool Overview.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/img/Virtual Threads DefaultCarrierPool Overview.png -------------------------------------------------------------------------------- /img/Virtual Threads List.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/img/Virtual Threads List.png -------------------------------------------------------------------------------- /img/Virtual Threads Overview.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/mp911de/spring-boot-virtual-threads-experiment/6efa152aafe1b888fca495fe6f6015ef6ee500ee/img/Virtual Threads Overview.png -------------------------------------------------------------------------------- /mvnw: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | # ---------------------------------------------------------------------------- 3 | # Licensed to the Apache Software Foundation (ASF) under one 4 | # or more contributor license agreements. See the NOTICE file 5 | # distributed with this work for additional information 6 | # regarding copyright ownership. The ASF licenses this file 7 | # to you under the Apache License, Version 2.0 (the 8 | # "License"); you may not use this file except in compliance 9 | # with the License. You may obtain a copy of the License at 10 | # 11 | # https://www.apache.org/licenses/LICENSE-2.0 12 | # 13 | # Unless required by applicable law or agreed to in writing, 14 | # software distributed under the License is distributed on an 15 | # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 | # KIND, either express or implied. See the License for the 17 | # specific language governing permissions and limitations 18 | # under the License. 19 | # ---------------------------------------------------------------------------- 20 | 21 | # ---------------------------------------------------------------------------- 22 | # Maven Start Up Batch script 23 | # 24 | # Required ENV vars: 25 | # ------------------ 26 | # JAVA_HOME - location of a JDK home dir 27 | # 28 | # Optional ENV vars 29 | # ----------------- 30 | # M2_HOME - location of maven2's installed home dir 31 | # MAVEN_OPTS - parameters passed to the Java VM when running Maven 32 | # e.g. to debug Maven itself, use 33 | # set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000 34 | # MAVEN_SKIP_RC - flag to disable loading of mavenrc files 35 | # ---------------------------------------------------------------------------- 36 | 37 | if [ -z "$MAVEN_SKIP_RC" ] ; then 38 | 39 | if [ -f /etc/mavenrc ] ; then 40 | . /etc/mavenrc 41 | fi 42 | 43 | if [ -f "$HOME/.mavenrc" ] ; then 44 | . "$HOME/.mavenrc" 45 | fi 46 | 47 | fi 48 | 49 | # OS specific support. $var _must_ be set to either true or false. 50 | cygwin=false; 51 | darwin=false; 52 | mingw=false 53 | case "`uname`" in 54 | CYGWIN*) cygwin=true ;; 55 | MINGW*) mingw=true;; 56 | Darwin*) darwin=true 57 | # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home 58 | # See https://developer.apple.com/library/mac/qa/qa1170/_index.html 59 | if [ -z "$JAVA_HOME" ]; then 60 | if [ -x "/usr/libexec/java_home" ]; then 61 | export JAVA_HOME="`/usr/libexec/java_home`" 62 | else 63 | export JAVA_HOME="/Library/Java/Home" 64 | fi 65 | fi 66 | ;; 67 | esac 68 | 69 | if [ -z "$JAVA_HOME" ] ; then 70 | if [ -r /etc/gentoo-release ] ; then 71 | JAVA_HOME=`java-config --jre-home` 72 | fi 73 | fi 74 | 75 | if [ -z "$M2_HOME" ] ; then 76 | ## resolve links - $0 may be a link to maven's home 77 | PRG="$0" 78 | 79 | # need this for relative symlinks 80 | while [ -h "$PRG" ] ; do 81 | ls=`ls -ld "$PRG"` 82 | link=`expr "$ls" : '.*-> \(.*\)$'` 83 | if expr "$link" : '/.*' > /dev/null; then 84 | PRG="$link" 85 | else 86 | PRG="`dirname "$PRG"`/$link" 87 | fi 88 | done 89 | 90 | saveddir=`pwd` 91 | 92 | M2_HOME=`dirname "$PRG"`/.. 93 | 94 | # make it fully qualified 95 | M2_HOME=`cd "$M2_HOME" && pwd` 96 | 97 | cd "$saveddir" 98 | # echo Using m2 at $M2_HOME 99 | fi 100 | 101 | # For Cygwin, ensure paths are in UNIX format before anything is touched 102 | if $cygwin ; then 103 | [ -n "$M2_HOME" ] && 104 | M2_HOME=`cygpath --unix "$M2_HOME"` 105 | [ -n "$JAVA_HOME" ] && 106 | JAVA_HOME=`cygpath --unix "$JAVA_HOME"` 107 | [ -n "$CLASSPATH" ] && 108 | CLASSPATH=`cygpath --path --unix "$CLASSPATH"` 109 | fi 110 | 111 | # For Mingw, ensure paths are in UNIX format before anything is touched 112 | if $mingw ; then 113 | [ -n "$M2_HOME" ] && 114 | M2_HOME="`(cd "$M2_HOME"; pwd)`" 115 | [ -n "$JAVA_HOME" ] && 116 | JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`" 117 | fi 118 | 119 | if [ -z "$JAVA_HOME" ]; then 120 | javaExecutable="`which javac`" 121 | if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then 122 | # readlink(1) is not available as standard on Solaris 10. 123 | readLink=`which readlink` 124 | if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then 125 | if $darwin ; then 126 | javaHome="`dirname \"$javaExecutable\"`" 127 | javaExecutable="`cd \"$javaHome\" && pwd -P`/javac" 128 | else 129 | javaExecutable="`readlink -f \"$javaExecutable\"`" 130 | fi 131 | javaHome="`dirname \"$javaExecutable\"`" 132 | javaHome=`expr "$javaHome" : '\(.*\)/bin'` 133 | JAVA_HOME="$javaHome" 134 | export JAVA_HOME 135 | fi 136 | fi 137 | fi 138 | 139 | if [ -z "$JAVACMD" ] ; then 140 | if [ -n "$JAVA_HOME" ] ; then 141 | if [ -x "$JAVA_HOME/jre/sh/java" ] ; then 142 | # IBM's JDK on AIX uses strange locations for the executables 143 | JAVACMD="$JAVA_HOME/jre/sh/java" 144 | else 145 | JAVACMD="$JAVA_HOME/bin/java" 146 | fi 147 | else 148 | JAVACMD="`which java`" 149 | fi 150 | fi 151 | 152 | if [ ! -x "$JAVACMD" ] ; then 153 | echo "Error: JAVA_HOME is not defined correctly." >&2 154 | echo " We cannot execute $JAVACMD" >&2 155 | exit 1 156 | fi 157 | 158 | if [ -z "$JAVA_HOME" ] ; then 159 | echo "Warning: JAVA_HOME environment variable is not set." 160 | fi 161 | 162 | CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher 163 | 164 | # traverses directory structure from process work directory to filesystem root 165 | # first directory with .mvn subdirectory is considered project base directory 166 | find_maven_basedir() { 167 | 168 | if [ -z "$1" ] 169 | then 170 | echo "Path not specified to find_maven_basedir" 171 | return 1 172 | fi 173 | 174 | basedir="$1" 175 | wdir="$1" 176 | while [ "$wdir" != '/' ] ; do 177 | if [ -d "$wdir"/.mvn ] ; then 178 | basedir=$wdir 179 | break 180 | fi 181 | # workaround for JBEAP-8937 (on Solaris 10/Sparc) 182 | if [ -d "${wdir}" ]; then 183 | wdir=`cd "$wdir/.."; pwd` 184 | fi 185 | # end of workaround 186 | done 187 | echo "${basedir}" 188 | } 189 | 190 | # concatenates all lines of a file 191 | concat_lines() { 192 | if [ -f "$1" ]; then 193 | echo "$(tr -s '\n' ' ' < "$1")" 194 | fi 195 | } 196 | 197 | BASE_DIR=`find_maven_basedir "$(pwd)"` 198 | if [ -z "$BASE_DIR" ]; then 199 | exit 1; 200 | fi 201 | 202 | ########################################################################################## 203 | # Extension to allow automatically downloading the maven-wrapper.jar from Maven-central 204 | # This allows using the maven wrapper in projects that prohibit checking in binary data. 205 | ########################################################################################## 206 | if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then 207 | if [ "$MVNW_VERBOSE" = true ]; then 208 | echo "Found .mvn/wrapper/maven-wrapper.jar" 209 | fi 210 | else 211 | if [ "$MVNW_VERBOSE" = true ]; then 212 | echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..." 213 | fi 214 | if [ -n "$MVNW_REPOURL" ]; then 215 | jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar" 216 | else 217 | jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar" 218 | fi 219 | while IFS="=" read key value; do 220 | case "$key" in (wrapperUrl) jarUrl="$value"; break ;; 221 | esac 222 | done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties" 223 | if [ "$MVNW_VERBOSE" = true ]; then 224 | echo "Downloading from: $jarUrl" 225 | fi 226 | wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" 227 | if $cygwin; then 228 | wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"` 229 | fi 230 | 231 | if command -v wget > /dev/null; then 232 | if [ "$MVNW_VERBOSE" = true ]; then 233 | echo "Found wget ... using wget" 234 | fi 235 | if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then 236 | wget "$jarUrl" -O "$wrapperJarPath" 237 | else 238 | wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath" 239 | fi 240 | elif command -v curl > /dev/null; then 241 | if [ "$MVNW_VERBOSE" = true ]; then 242 | echo "Found curl ... using curl" 243 | fi 244 | if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then 245 | curl -o "$wrapperJarPath" "$jarUrl" -f 246 | else 247 | curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f 248 | fi 249 | 250 | else 251 | if [ "$MVNW_VERBOSE" = true ]; then 252 | echo "Falling back to using Java to download" 253 | fi 254 | javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java" 255 | # For Cygwin, switch paths to Windows format before running javac 256 | if $cygwin; then 257 | javaClass=`cygpath --path --windows "$javaClass"` 258 | fi 259 | if [ -e "$javaClass" ]; then 260 | if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then 261 | if [ "$MVNW_VERBOSE" = true ]; then 262 | echo " - Compiling MavenWrapperDownloader.java ..." 263 | fi 264 | # Compiling the Java class 265 | ("$JAVA_HOME/bin/javac" "$javaClass") 266 | fi 267 | if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then 268 | # Running the downloader 269 | if [ "$MVNW_VERBOSE" = true ]; then 270 | echo " - Running MavenWrapperDownloader.java ..." 271 | fi 272 | ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR") 273 | fi 274 | fi 275 | fi 276 | fi 277 | ########################################################################################## 278 | # End of extension 279 | ########################################################################################## 280 | 281 | export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"} 282 | if [ "$MVNW_VERBOSE" = true ]; then 283 | echo $MAVEN_PROJECTBASEDIR 284 | fi 285 | MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS" 286 | 287 | # For Cygwin, switch paths to Windows format before running java 288 | if $cygwin; then 289 | [ -n "$M2_HOME" ] && 290 | M2_HOME=`cygpath --path --windows "$M2_HOME"` 291 | [ -n "$JAVA_HOME" ] && 292 | JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"` 293 | [ -n "$CLASSPATH" ] && 294 | CLASSPATH=`cygpath --path --windows "$CLASSPATH"` 295 | [ -n "$MAVEN_PROJECTBASEDIR" ] && 296 | MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"` 297 | fi 298 | 299 | # Provide a "standardized" way to retrieve the CLI args that will 300 | # work with both Windows and non-Windows executions. 301 | MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@" 302 | export MAVEN_CMD_LINE_ARGS 303 | 304 | WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain 305 | 306 | exec "$JAVACMD" \ 307 | $MAVEN_OPTS \ 308 | -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \ 309 | "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \ 310 | ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@" 311 | -------------------------------------------------------------------------------- /mvnw.cmd: -------------------------------------------------------------------------------- 1 | @REM ---------------------------------------------------------------------------- 2 | @REM Licensed to the Apache Software Foundation (ASF) under one 3 | @REM or more contributor license agreements. See the NOTICE file 4 | @REM distributed with this work for additional information 5 | @REM regarding copyright ownership. The ASF licenses this file 6 | @REM to you under the Apache License, Version 2.0 (the 7 | @REM "License"); you may not use this file except in compliance 8 | @REM with the License. You may obtain a copy of the License at 9 | @REM 10 | @REM https://www.apache.org/licenses/LICENSE-2.0 11 | @REM 12 | @REM Unless required by applicable law or agreed to in writing, 13 | @REM software distributed under the License is distributed on an 14 | @REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 | @REM KIND, either express or implied. See the License for the 16 | @REM specific language governing permissions and limitations 17 | @REM under the License. 18 | @REM ---------------------------------------------------------------------------- 19 | 20 | @REM ---------------------------------------------------------------------------- 21 | @REM Maven Start Up Batch script 22 | @REM 23 | @REM Required ENV vars: 24 | @REM JAVA_HOME - location of a JDK home dir 25 | @REM 26 | @REM Optional ENV vars 27 | @REM M2_HOME - location of maven2's installed home dir 28 | @REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands 29 | @REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending 30 | @REM MAVEN_OPTS - parameters passed to the Java VM when running Maven 31 | @REM e.g. to debug Maven itself, use 32 | @REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000 33 | @REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files 34 | @REM ---------------------------------------------------------------------------- 35 | 36 | @REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on' 37 | @echo off 38 | @REM set title of command window 39 | title %0 40 | @REM enable echoing by setting MAVEN_BATCH_ECHO to 'on' 41 | @if "%MAVEN_BATCH_ECHO%" == "on" echo %MAVEN_BATCH_ECHO% 42 | 43 | @REM set %HOME% to equivalent of $HOME 44 | if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%") 45 | 46 | @REM Execute a user defined script before this one 47 | if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre 48 | @REM check for pre script, once with legacy .bat ending and once with .cmd ending 49 | if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat" 50 | if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd" 51 | :skipRcPre 52 | 53 | @setlocal 54 | 55 | set ERROR_CODE=0 56 | 57 | @REM To isolate internal variables from possible post scripts, we use another setlocal 58 | @setlocal 59 | 60 | @REM ==== START VALIDATION ==== 61 | if not "%JAVA_HOME%" == "" goto OkJHome 62 | 63 | echo. 64 | echo Error: JAVA_HOME not found in your environment. >&2 65 | echo Please set the JAVA_HOME variable in your environment to match the >&2 66 | echo location of your Java installation. >&2 67 | echo. 68 | goto error 69 | 70 | :OkJHome 71 | if exist "%JAVA_HOME%\bin\java.exe" goto init 72 | 73 | echo. 74 | echo Error: JAVA_HOME is set to an invalid directory. >&2 75 | echo JAVA_HOME = "%JAVA_HOME%" >&2 76 | echo Please set the JAVA_HOME variable in your environment to match the >&2 77 | echo location of your Java installation. >&2 78 | echo. 79 | goto error 80 | 81 | @REM ==== END VALIDATION ==== 82 | 83 | :init 84 | 85 | @REM Find the project base dir, i.e. the directory that contains the folder ".mvn". 86 | @REM Fallback to current working directory if not found. 87 | 88 | set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR% 89 | IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir 90 | 91 | set EXEC_DIR=%CD% 92 | set WDIR=%EXEC_DIR% 93 | :findBaseDir 94 | IF EXIST "%WDIR%"\.mvn goto baseDirFound 95 | cd .. 96 | IF "%WDIR%"=="%CD%" goto baseDirNotFound 97 | set WDIR=%CD% 98 | goto findBaseDir 99 | 100 | :baseDirFound 101 | set MAVEN_PROJECTBASEDIR=%WDIR% 102 | cd "%EXEC_DIR%" 103 | goto endDetectBaseDir 104 | 105 | :baseDirNotFound 106 | set MAVEN_PROJECTBASEDIR=%EXEC_DIR% 107 | cd "%EXEC_DIR%" 108 | 109 | :endDetectBaseDir 110 | 111 | IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig 112 | 113 | @setlocal EnableExtensions EnableDelayedExpansion 114 | for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a 115 | @endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS% 116 | 117 | :endReadAdditionalConfig 118 | 119 | SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe" 120 | set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar" 121 | set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain 122 | 123 | set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar" 124 | 125 | FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO ( 126 | IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B 127 | ) 128 | 129 | @REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central 130 | @REM This allows using the maven wrapper in projects that prohibit checking in binary data. 131 | if exist %WRAPPER_JAR% ( 132 | if "%MVNW_VERBOSE%" == "true" ( 133 | echo Found %WRAPPER_JAR% 134 | ) 135 | ) else ( 136 | if not "%MVNW_REPOURL%" == "" ( 137 | SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar" 138 | ) 139 | if "%MVNW_VERBOSE%" == "true" ( 140 | echo Couldn't find %WRAPPER_JAR%, downloading it ... 141 | echo Downloading from: %DOWNLOAD_URL% 142 | ) 143 | 144 | powershell -Command "&{"^ 145 | "$webclient = new-object System.Net.WebClient;"^ 146 | "if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^ 147 | "$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^ 148 | "}"^ 149 | "[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^ 150 | "}" 151 | if "%MVNW_VERBOSE%" == "true" ( 152 | echo Finished downloading %WRAPPER_JAR% 153 | ) 154 | ) 155 | @REM End of extension 156 | 157 | @REM Provide a "standardized" way to retrieve the CLI args that will 158 | @REM work with both Windows and non-Windows executions. 159 | set MAVEN_CMD_LINE_ARGS=%* 160 | 161 | %MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %* 162 | if ERRORLEVEL 1 goto error 163 | goto end 164 | 165 | :error 166 | set ERROR_CODE=1 167 | 168 | :end 169 | @endlocal & set ERROR_CODE=%ERROR_CODE% 170 | 171 | if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost 172 | @REM check for post script, once with legacy .bat ending and once with .cmd ending 173 | if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat" 174 | if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd" 175 | :skipRcPost 176 | 177 | @REM pause the script if MAVEN_BATCH_PAUSE is set to 'on' 178 | if "%MAVEN_BATCH_PAUSE%" == "on" pause 179 | 180 | if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE% 181 | 182 | exit /B %ERROR_CODE% 183 | -------------------------------------------------------------------------------- /pom.xml: -------------------------------------------------------------------------------- 1 | 2 | 5 | 4.0.0 6 | 7 | org.springframework.boot 8 | spring-boot-starter-parent 9 | 3.0.0-M4 10 | 11 | 12 | com.example 13 | loom-servlet 14 | 0.0.1-SNAPSHOT 15 | loom-servlet 16 | Demo project for Spring Boot 17 | 18 | 19 | 19 20 | 10.1.0-M17 21 | 22 | 23 | 24 | 25 | org.springframework.boot 26 | spring-boot-starter-data-jdbc 27 | 28 | 29 | org.springframework.boot 30 | spring-boot-starter-web 31 | 32 | 33 | 34 | org.postgresql 35 | postgresql 36 | runtime 37 | 38 | 39 | 40 | org.springframework.boot 41 | spring-boot-starter-test 42 | test 43 | 44 | 45 | 46 | 47 | 48 | 49 | org.apache.maven.plugins 50 | maven-compiler-plugin 51 | 52 | --enable-preview 53 | 54 | 55 | 56 | org.apache.maven.plugins 57 | maven-surefire-plugin 58 | 59 | --enable-preview 60 | 61 | 62 | 63 | org.springframework.boot 64 | spring-boot-maven-plugin 65 | 66 | --enable-preview 67 | 68 | 69 | 70 | 71 | 72 | 73 | 74 | spring-libs-milestone 75 | https://repo.spring.io/libs-milestone 76 | 77 | 78 | 79 | 80 | 81 | spring-libs-milestone 82 | https://repo.spring.io/libs-milestone 83 | 84 | 85 | 86 | 87 | -------------------------------------------------------------------------------- /src/main/java/com/example/loomservlet/ServletOfTheLoomApplication.java: -------------------------------------------------------------------------------- 1 | package com.example.loomservlet; 2 | 3 | import java.util.concurrent.Callable; 4 | import java.util.concurrent.ExecutorService; 5 | import java.util.concurrent.Executors; 6 | 7 | import org.springframework.boot.SpringApplication; 8 | import org.springframework.boot.autoconfigure.SpringBootApplication; 9 | import org.springframework.boot.web.embedded.tomcat.TomcatProtocolHandlerCustomizer; 10 | import org.springframework.context.annotation.Bean; 11 | import org.springframework.core.task.AsyncTaskExecutor; 12 | import org.springframework.core.task.support.TaskExecutorAdapter; 13 | import org.springframework.jdbc.core.JdbcTemplate; 14 | import org.springframework.web.bind.annotation.GetMapping; 15 | import org.springframework.web.bind.annotation.RestController; 16 | 17 | @SpringBootApplication 18 | public class ServletOfTheLoomApplication { 19 | 20 | public static void main(String[] args) { 21 | SpringApplication.run(ServletOfTheLoomApplication.class, args); 22 | } 23 | 24 | @Bean 25 | AsyncTaskExecutor applicationTaskExecutor() { 26 | // enable async servlet support 27 | ExecutorService executorService = Executors.newVirtualThreadPerTaskExecutor(); 28 | return new TaskExecutorAdapter(executorService::execute); 29 | } 30 | 31 | @Bean 32 | TomcatProtocolHandlerCustomizer protocolHandlerVirtualThreadExecutorCustomizer() { 33 | 34 | return protocolHandler -> { 35 | protocolHandler.setExecutor(Executors.newVirtualThreadPerTaskExecutor()); 36 | }; 37 | } 38 | 39 | @RestController 40 | static class MyController { 41 | 42 | final JdbcTemplate jdbcTemplate; 43 | 44 | MyController(JdbcTemplate jdbcTemplate) { 45 | this.jdbcTemplate = jdbcTemplate; 46 | } 47 | 48 | @GetMapping("/") 49 | String getValue() throws InterruptedException { 50 | 51 | // Simulate a blocking call for one second. The thread should be put aside for about a second. 52 | Thread.sleep(1000); 53 | return "OK"; 54 | } 55 | 56 | @GetMapping("/where-am-i") 57 | String getThreadName() { 58 | return Thread.currentThread().toString(); 59 | } 60 | 61 | @GetMapping("/where-am-i-async") 62 | Callable getAsyncThreadName() { 63 | return () -> Thread.currentThread().toString(); 64 | } 65 | 66 | @GetMapping("/sql") 67 | String getFromDatabase() { 68 | 69 | // Simulate blocking I/O where the server side controls the timeout. The thread should be put aside for about a second. 70 | return jdbcTemplate.queryForList("select pg_sleep(1);").toString(); 71 | } 72 | } 73 | 74 | } 75 | -------------------------------------------------------------------------------- /src/main/resources/application.properties: -------------------------------------------------------------------------------- 1 | spring.datasource.driver-class-name=org.postgresql.Driver 2 | spring.datasource.url=jdbc:postgresql://localhost:5432/postgres 3 | spring.datasource.username=postgres 4 | spring.datasource.password=postgres 5 | --------------------------------------------------------------------------------