Add demo for new Spring Boot Upgrade report

Author: fabapp2

demos/spring-boot-3-upgrade-demo/.gitignore

@@ -0,0 +1 @@
+demo-spring-song-app

demos/spring-boot-3-upgrade-demo/run-demo.sh

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+#!/bin/sh
+
+scriptDir=$(dirname "${BASH_SOURCE[0]}")
+projectRoot=$scriptDir/../..
+webApp=$projectRoot/applications/spring-boot-upgrade
+demoApp="$scriptDir/demo-spring-song-app"
+applicationJar="${webApp}/target/spring-boot-upgrade.jar"
+
+function pause(){
+  echo    "=============================================================================================="
+  echo    " -> $*"
+  echo    " Press Enter to continue..."
+  read -p "=============================================================================================="
+}
+
+function build() {
+  # build sbm
+  pushd "${projectRoot}" || exit
+  mvn clean install -DskipTests
+  popd
+}
+
+function buildIfGitStatusNotClean() {
+  git update-index --really-refresh >> /dev/null
+  if [[ ! `git diff-index --quiet HEAD` ]] || [[ ! -f "${webApp}/target/spring-boot-upgrade.jar" ]]; then
+    echo "git status not clean, building project"
+    build
+  fi
+}
+
+
+# cleanup
+rm -rf "$demoApp"
+
+buildIfGitStatusNotClean
+
+# checkout demo project
+git clone https://github.com/sanagaraj-pivotal/demo-spring-song-app.git $demoApp
+pushd "$demoApp" || exit
+git checkout -b boot-3-upgrade-demo tags/demo
+idea .
+popd
+
+pause "kill process currently running under port 8080"
+lsof -i :8080 | awk '{system("kill -9 " $2)}'
+
+# start webapp
+java -jar --add-opens java.base/sun.nio.ch=ALL-UNNAMED --add-opens java.base/java.io=ALL-UNNAMED $applicationJar $demoApp