refactor

.gitattributes

@@ -0,0 +1,2 @@
+/mvnw text eol=lf
+*.cmd text eol=crlf

.gitignore

@@ -0,0 +1,34 @@
+.envrc
+HELP.md
+target/
+.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,19 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, 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.
+wrapperVersion=3.3.2
+distributionType=only-script
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.11/apache-maven-3.9.11-bin.zip

mvnw

@@ -0,0 +1,259 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, 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.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Apache Maven Wrapper startup batch script, version 3.3.2
+#
+# Optional ENV vars
+# -----------------
+#   JAVA_HOME - location of a JDK home dir, required when download maven via java source
+#   MVNW_REPOURL - repo url base for downloading maven distribution
+#   MVNW_USERNAME/MVNW_PASSWORD - user and password for downloading maven
+#   MVNW_VERBOSE - true: enable verbose log; debug: trace the mvnw script; others: silence the output
+# ----------------------------------------------------------------------------
+
+set -euf
+[ "${MVNW_VERBOSE-}" != debug ] || set -x
+
+# OS specific support.
+native_path() { printf %s\\n "$1"; }
+case "$(uname)" in
+CYGWIN* | MINGW*)
+  [ -z "${JAVA_HOME-}" ] || JAVA_HOME="$(cygpath --unix "$JAVA_HOME")"
+  native_path() { cygpath --path --windows "$1"; }
+  ;;
+esac
+
+# set JAVACMD and JAVACCMD
+set_java_home() {
+  # For Cygwin and MinGW, ensure paths are in Unix format before anything is touched
+  if [ -n "${JAVA_HOME-}" ]; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ]; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+      JAVACCMD="$JAVA_HOME/jre/sh/javac"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+      JAVACCMD="$JAVA_HOME/bin/javac"
+
+      if [ ! -x "$JAVACMD" ] || [ ! -x "$JAVACCMD" ]; then
+        echo "The JAVA_HOME environment variable is not defined correctly, so mvnw cannot run." >&2
+        echo "JAVA_HOME is set to \"$JAVA_HOME\", but \"\$JAVA_HOME/bin/java\" or \"\$JAVA_HOME/bin/javac\" does not exist." >&2
+        return 1
+      fi
+    fi
+  else
+    JAVACMD="$(
+      'set' +e
+      'unset' -f command 2>/dev/null
+      'command' -v java
+    )" || :
+    JAVACCMD="$(
+      'set' +e
+      'unset' -f command 2>/dev/null
+      'command' -v javac
+    )" || :
+
+    if [ ! -x "${JAVACMD-}" ] || [ ! -x "${JAVACCMD-}" ]; then
+      echo "The java/javac command does not exist in PATH nor is JAVA_HOME set, so mvnw cannot run." >&2
+      return 1
+    fi
+  fi
+}
+
+# hash string like Java String::hashCode
+hash_string() {
+  str="${1:-}" h=0
+  while [ -n "$str" ]; do
+    char="${str%"${str#?}"}"
+    h=$(((h * 31 + $(LC_CTYPE=C printf %d "'$char")) % 4294967296))
+    str="${str#?}"
+  done
+  printf %x\\n $h
+}
+
+verbose() { :; }
+[ "${MVNW_VERBOSE-}" != true ] || verbose() { printf %s\\n "${1-}"; }
+
+die() {
+  printf %s\\n "$1" >&2
+  exit 1
+}
+
+trim() {
+  # MWRAPPER-139:
+  #   Trims trailing and leading whitespace, carriage returns, tabs, and linefeeds.
+  #   Needed for removing poorly interpreted newline sequences when running in more
+  #   exotic environments such as mingw bash on Windows.
+  printf "%s" "${1}" | tr -d '[:space:]'
+}
+
+# parse distributionUrl and optional distributionSha256Sum, requires .mvn/wrapper/maven-wrapper.properties
+while IFS="=" read -r key value; do
+  case "${key-}" in
+  distributionUrl) distributionUrl=$(trim "${value-}") ;;
+  distributionSha256Sum) distributionSha256Sum=$(trim "${value-}") ;;
+  esac
+done <"${0%/*}/.mvn/wrapper/maven-wrapper.properties"
+[ -n "${distributionUrl-}" ] || die "cannot read distributionUrl property in ${0%/*}/.mvn/wrapper/maven-wrapper.properties"
+
+case "${distributionUrl##*/}" in
+maven-mvnd-*bin.*)
+  MVN_CMD=mvnd.sh _MVNW_REPO_PATTERN=/maven/mvnd/
+  case "${PROCESSOR_ARCHITECTURE-}${PROCESSOR_ARCHITEW6432-}:$(uname -a)" in
+  *AMD64:CYGWIN* | *AMD64:MINGW*) distributionPlatform=windows-amd64 ;;
+  :Darwin*x86_64) distributionPlatform=darwin-amd64 ;;
+  :Darwin*arm64) distributionPlatform=darwin-aarch64 ;;
+  :Linux*x86_64*) distributionPlatform=linux-amd64 ;;
+  *)
+    echo "Cannot detect native platform for mvnd on $(uname)-$(uname -m), use pure java version" >&2
+    distributionPlatform=linux-amd64
+    ;;
+  esac
+  distributionUrl="${distributionUrl%-bin.*}-$distributionPlatform.zip"
+  ;;
+maven-mvnd-*) MVN_CMD=mvnd.sh _MVNW_REPO_PATTERN=/maven/mvnd/ ;;
+*) MVN_CMD="mvn${0##*/mvnw}" _MVNW_REPO_PATTERN=/org/apache/maven/ ;;
+esac
+
+# apply MVNW_REPOURL and calculate MAVEN_HOME
+# maven home pattern: ~/.m2/wrapper/dists/{apache-maven-<version>,maven-mvnd-<version>-<platform>}/<hash>
+[ -z "${MVNW_REPOURL-}" ] || distributionUrl="$MVNW_REPOURL$_MVNW_REPO_PATTERN${distributionUrl#*"$_MVNW_REPO_PATTERN"}"
+distributionUrlName="${distributionUrl##*/}"
+distributionUrlNameMain="${distributionUrlName%.*}"
+distributionUrlNameMain="${distributionUrlNameMain%-bin}"
+MAVEN_USER_HOME="${MAVEN_USER_HOME:-${HOME}/.m2}"
+MAVEN_HOME="${MAVEN_USER_HOME}/wrapper/dists/${distributionUrlNameMain-}/$(hash_string "$distributionUrl")"
+
+exec_maven() {
+  unset MVNW_VERBOSE MVNW_USERNAME MVNW_PASSWORD MVNW_REPOURL || :
+  exec "$MAVEN_HOME/bin/$MVN_CMD" "$@" || die "cannot exec $MAVEN_HOME/bin/$MVN_CMD"
+}
+
+if [ -d "$MAVEN_HOME" ]; then
+  verbose "found existing MAVEN_HOME at $MAVEN_HOME"
+  exec_maven "$@"
+fi
+
+case "${distributionUrl-}" in
+*?-bin.zip | *?maven-mvnd-?*-?*.zip) ;;
+*) die "distributionUrl is not valid, must match *-bin.zip or maven-mvnd-*.zip, but found '${distributionUrl-}'" ;;
+esac
+
+# prepare tmp dir
+if TMP_DOWNLOAD_DIR="$(mktemp -d)" && [ -d "$TMP_DOWNLOAD_DIR" ]; then
+  clean() { rm -rf -- "$TMP_DOWNLOAD_DIR"; }
+  trap clean HUP INT TERM EXIT
+else
+  die "cannot create temp dir"
+fi
+
+mkdir -p -- "${MAVEN_HOME%/*}"
+
+# Download and Install Apache Maven
+verbose "Couldn't find MAVEN_HOME, downloading and installing it ..."
+verbose "Downloading from: $distributionUrl"
+verbose "Downloading to: $TMP_DOWNLOAD_DIR/$distributionUrlName"
+
+# select .zip or .tar.gz
+if ! command -v unzip >/dev/null; then
+  distributionUrl="${distributionUrl%.zip}.tar.gz"
+  distributionUrlName="${distributionUrl##*/}"
+fi
+
+# verbose opt
+__MVNW_QUIET_WGET=--quiet __MVNW_QUIET_CURL=--silent __MVNW_QUIET_UNZIP=-q __MVNW_QUIET_TAR=''
+[ "${MVNW_VERBOSE-}" != true ] || __MVNW_QUIET_WGET='' __MVNW_QUIET_CURL='' __MVNW_QUIET_UNZIP='' __MVNW_QUIET_TAR=v
+
+# normalize http auth
+case "${MVNW_PASSWORD:+has-password}" in
+'') MVNW_USERNAME='' MVNW_PASSWORD='' ;;
+has-password) [ -n "${MVNW_USERNAME-}" ] || MVNW_USERNAME='' MVNW_PASSWORD='' ;;
+esac
+
+if [ -z "${MVNW_USERNAME-}" ] && command -v wget >/dev/null; then
+  verbose "Found wget ... using wget"
+  wget ${__MVNW_QUIET_WGET:+"$__MVNW_QUIET_WGET"} "$distributionUrl" -O "$TMP_DOWNLOAD_DIR/$distributionUrlName" || die "wget: Failed to fetch $distributionUrl"
+elif [ -z "${MVNW_USERNAME-}" ] && command -v curl >/dev/null; then
+  verbose "Found curl ... using curl"
+  curl ${__MVNW_QUIET_CURL:+"$__MVNW_QUIET_CURL"} -f -L -o "$TMP_DOWNLOAD_DIR/$distributionUrlName" "$distributionUrl" || die "curl: Failed to fetch $distributionUrl"
+elif set_java_home; then
+  verbose "Falling back to use Java to download"
+  javaSource="$TMP_DOWNLOAD_DIR/Downloader.java"
+  targetZip="$TMP_DOWNLOAD_DIR/$distributionUrlName"
+  cat >"$javaSource" <<-END
+	public class Downloader extends java.net.Authenticator
+	{
+	  protected java.net.PasswordAuthentication getPasswordAuthentication()
+	  {
+	    return new java.net.PasswordAuthentication( System.getenv( "MVNW_USERNAME" ), System.getenv( "MVNW_PASSWORD" ).toCharArray() );
+	  }
+	  public static void main( String[] args ) throws Exception
+	  {
+	    setDefault( new Downloader() );
+	    java.nio.file.Files.copy( java.net.URI.create( args[0] ).toURL().openStream(), java.nio.file.Paths.get( args[1] ).toAbsolutePath().normalize() );
+	  }
+	}
+	END
+  # For Cygwin/MinGW, switch paths to Windows format before running javac and java
+  verbose " - Compiling Downloader.java ..."
+  "$(native_path "$JAVACCMD")" "$(native_path "$javaSource")" || die "Failed to compile Downloader.java"
+  verbose " - Running Downloader.java ..."
+  "$(native_path "$JAVACMD")" -cp "$(native_path "$TMP_DOWNLOAD_DIR")" Downloader "$distributionUrl" "$(native_path "$targetZip")"
+fi
+
+# If specified, validate the SHA-256 sum of the Maven distribution zip file
+if [ -n "${distributionSha256Sum-}" ]; then
+  distributionSha256Result=false
+  if [ "$MVN_CMD" = mvnd.sh ]; then
+    echo "Checksum validation is not supported for maven-mvnd." >&2
+    echo "Please disable validation by removing 'distributionSha256Sum' from your maven-wrapper.properties." >&2
+    exit 1
+  elif command -v sha256sum >/dev/null; then
+    if echo "$distributionSha256Sum  $TMP_DOWNLOAD_DIR/$distributionUrlName" | sha256sum -c >/dev/null 2>&1; then
+      distributionSha256Result=true
+    fi
+  elif command -v shasum >/dev/null; then
+    if echo "$distributionSha256Sum  $TMP_DOWNLOAD_DIR/$distributionUrlName" | shasum -a 256 -c >/dev/null 2>&1; then
+      distributionSha256Result=true
+    fi
+  else
+    echo "Checksum validation was requested but neither 'sha256sum' or 'shasum' are available." >&2
+    echo "Please install either command, or disable validation by removing 'distributionSha256Sum' from your maven-wrapper.properties." >&2
+    exit 1
+  fi
+  if [ $distributionSha256Result = false ]; then
+    echo "Error: Failed to validate Maven distribution SHA-256, your Maven distribution might be compromised." >&2
+    echo "If you updated your Maven version, you need to update the specified distributionSha256Sum property." >&2
+    exit 1
+  fi
+fi
+
+# unzip and move
+if command -v unzip >/dev/null; then
+  unzip ${__MVNW_QUIET_UNZIP:+"$__MVNW_QUIET_UNZIP"} "$TMP_DOWNLOAD_DIR/$distributionUrlName" -d "$TMP_DOWNLOAD_DIR" || die "failed to unzip"
+else
+  tar xzf${__MVNW_QUIET_TAR:+"$__MVNW_QUIET_TAR"} "$TMP_DOWNLOAD_DIR/$distributionUrlName" -C "$TMP_DOWNLOAD_DIR" || die "failed to untar"
+fi
+printf %s\\n "$distributionUrl" >"$TMP_DOWNLOAD_DIR/$distributionUrlNameMain/mvnw.url"
+mv -- "$TMP_DOWNLOAD_DIR/$distributionUrlNameMain" "$MAVEN_HOME" || [ -d "$MAVEN_HOME" ] || die "fail to move MAVEN_HOME"
+
+clean || :
+exec_maven "$@"

mvnw.cmd

@@ -0,0 +1,149 @@
+<# : batch portion
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Apache Maven Wrapper startup batch script, version 3.3.2
+@REM
+@REM Optional ENV vars
+@REM   MVNW_REPOURL - repo url base for downloading maven distribution
+@REM   MVNW_USERNAME/MVNW_PASSWORD - user and password for downloading maven
+@REM   MVNW_VERBOSE - true: enable verbose log; others: silence the output
+@REM ----------------------------------------------------------------------------
+
+@IF "%__MVNW_ARG0_NAME__%"=="" (SET __MVNW_ARG0_NAME__=%~nx0)
+@SET __MVNW_CMD__=
+@SET __MVNW_ERROR__=
+@SET __MVNW_PSMODULEP_SAVE=%PSModulePath%
+@SET PSModulePath=
+@FOR /F "usebackq tokens=1* delims==" %%A IN (`powershell -noprofile "& {$scriptDir='%~dp0'; $script='%__MVNW_ARG0_NAME__%'; icm -ScriptBlock ([Scriptblock]::Create((Get-Content -Raw '%~f0'))) -NoNewScope}"`) DO @(
+  IF "%%A"=="MVN_CMD" (set __MVNW_CMD__=%%B) ELSE IF "%%B"=="" (echo %%A) ELSE (echo %%A=%%B)
+)
+@SET PSModulePath=%__MVNW_PSMODULEP_SAVE%
+@SET __MVNW_PSMODULEP_SAVE=
+@SET __MVNW_ARG0_NAME__=
+@SET MVNW_USERNAME=
+@SET MVNW_PASSWORD=
+@IF NOT "%__MVNW_CMD__%"=="" (%__MVNW_CMD__% %*)
+@echo Cannot start maven from wrapper >&2 && exit /b 1
+@GOTO :EOF
+: end batch / begin powershell #>
+
+$ErrorActionPreference = "Stop"
+if ($env:MVNW_VERBOSE -eq "true") {
+  $VerbosePreference = "Continue"
+}
+
+# calculate distributionUrl, requires .mvn/wrapper/maven-wrapper.properties
+$distributionUrl = (Get-Content -Raw "$scriptDir/.mvn/wrapper/maven-wrapper.properties" | ConvertFrom-StringData).distributionUrl
+if (!$distributionUrl) {
+  Write-Error "cannot read distributionUrl property in $scriptDir/.mvn/wrapper/maven-wrapper.properties"
+}
+
+switch -wildcard -casesensitive ( $($distributionUrl -replace '^.*/','') ) {
+  "maven-mvnd-*" {
+    $USE_MVND = $true
+    $distributionUrl = $distributionUrl -replace '-bin\.[^.]*$',"-windows-amd64.zip"
+    $MVN_CMD = "mvnd.cmd"
+    break
+  }
+  default {
+    $USE_MVND = $false
+    $MVN_CMD = $script -replace '^mvnw','mvn'
+    break
+  }
+}
+
+# apply MVNW_REPOURL and calculate MAVEN_HOME
+# maven home pattern: ~/.m2/wrapper/dists/{apache-maven-<version>,maven-mvnd-<version>-<platform>}/<hash>
+if ($env:MVNW_REPOURL) {
+  $MVNW_REPO_PATTERN = if ($USE_MVND) { "/org/apache/maven/" } else { "/maven/mvnd/" }
+  $distributionUrl = "$env:MVNW_REPOURL$MVNW_REPO_PATTERN$($distributionUrl -replace '^.*'+$MVNW_REPO_PATTERN,'')"
+}
+$distributionUrlName = $distributionUrl -replace '^.*/',''
+$distributionUrlNameMain = $distributionUrlName -replace '\.[^.]*$','' -replace '-bin$',''
+$MAVEN_HOME_PARENT = "$HOME/.m2/wrapper/dists/$distributionUrlNameMain"
+if ($env:MAVEN_USER_HOME) {
+  $MAVEN_HOME_PARENT = "$env:MAVEN_USER_HOME/wrapper/dists/$distributionUrlNameMain"
+}
+$MAVEN_HOME_NAME = ([System.Security.Cryptography.MD5]::Create().ComputeHash([byte[]][char[]]$distributionUrl) | ForEach-Object {$_.ToString("x2")}) -join ''
+$MAVEN_HOME = "$MAVEN_HOME_PARENT/$MAVEN_HOME_NAME"
+
+if (Test-Path -Path "$MAVEN_HOME" -PathType Container) {
+  Write-Verbose "found existing MAVEN_HOME at $MAVEN_HOME"
+  Write-Output "MVN_CMD=$MAVEN_HOME/bin/$MVN_CMD"
+  exit $?
+}
+
+if (! $distributionUrlNameMain -or ($distributionUrlName -eq $distributionUrlNameMain)) {
+  Write-Error "distributionUrl is not valid, must end with *-bin.zip, but found $distributionUrl"
+}
+
+# prepare tmp dir
+$TMP_DOWNLOAD_DIR_HOLDER = New-TemporaryFile
+$TMP_DOWNLOAD_DIR = New-Item -Itemtype Directory -Path "$TMP_DOWNLOAD_DIR_HOLDER.dir"
+$TMP_DOWNLOAD_DIR_HOLDER.Delete() | Out-Null
+trap {
+  if ($TMP_DOWNLOAD_DIR.Exists) {
+    try { Remove-Item $TMP_DOWNLOAD_DIR -Recurse -Force | Out-Null }
+    catch { Write-Warning "Cannot remove $TMP_DOWNLOAD_DIR" }
+  }
+}
+
+New-Item -Itemtype Directory -Path "$MAVEN_HOME_PARENT" -Force | Out-Null
+
+# Download and Install Apache Maven
+Write-Verbose "Couldn't find MAVEN_HOME, downloading and installing it ..."
+Write-Verbose "Downloading from: $distributionUrl"
+Write-Verbose "Downloading to: $TMP_DOWNLOAD_DIR/$distributionUrlName"
+
+$webclient = New-Object System.Net.WebClient
+if ($env:MVNW_USERNAME -and $env:MVNW_PASSWORD) {
+  $webclient.Credentials = New-Object System.Net.NetworkCredential($env:MVNW_USERNAME, $env:MVNW_PASSWORD)
+}
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+$webclient.DownloadFile($distributionUrl, "$TMP_DOWNLOAD_DIR/$distributionUrlName") | Out-Null
+
+# If specified, validate the SHA-256 sum of the Maven distribution zip file
+$distributionSha256Sum = (Get-Content -Raw "$scriptDir/.mvn/wrapper/maven-wrapper.properties" | ConvertFrom-StringData).distributionSha256Sum
+if ($distributionSha256Sum) {
+  if ($USE_MVND) {
+    Write-Error "Checksum validation is not supported for maven-mvnd. `nPlease disable validation by removing 'distributionSha256Sum' from your maven-wrapper.properties."
+  }
+  Import-Module $PSHOME\Modules\Microsoft.PowerShell.Utility -Function Get-FileHash
+  if ((Get-FileHash "$TMP_DOWNLOAD_DIR/$distributionUrlName" -Algorithm SHA256).Hash.ToLower() -ne $distributionSha256Sum) {
+    Write-Error "Error: Failed to validate Maven distribution SHA-256, your Maven distribution might be compromised. If you updated your Maven version, you need to update the specified distributionSha256Sum property."
+  }
+}
+
+# unzip and move
+Expand-Archive "$TMP_DOWNLOAD_DIR/$distributionUrlName" -DestinationPath "$TMP_DOWNLOAD_DIR" | Out-Null
+Rename-Item -Path "$TMP_DOWNLOAD_DIR/$distributionUrlNameMain" -NewName $MAVEN_HOME_NAME | Out-Null
+try {
+  Move-Item -Path "$TMP_DOWNLOAD_DIR/$MAVEN_HOME_NAME" -Destination $MAVEN_HOME_PARENT | Out-Null
+} catch {
+  if (! (Test-Path -Path "$MAVEN_HOME" -PathType Container)) {
+    Write-Error "fail to move MAVEN_HOME"
+  }
+} finally {
+  try { Remove-Item $TMP_DOWNLOAD_DIR -Recurse -Force | Out-Null }
+  catch { Write-Warning "Cannot remove $TMP_DOWNLOAD_DIR" }
+}
+
+Write-Output "MVN_CMD=$MAVEN_HOME/bin/$MVN_CMD"

pom.xml

@@ -0,0 +1,193 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>3.5.4</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>app</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>app</name>
+	<description>Demo project for Spring Boot</description>
+	<url />
+	<licenses>
+		<license />
+	</licenses>
+	<developers>
+		<developer />
+	</developers>
+	<scm>
+		<connection />
+		<developerConnection />
+		<tag />
+		<url />
+	</scm>
+	<properties>
+		<java.version>24</java.version>
+		<grpc.version>1.72.0</grpc.version>
+		<protobuf-java.version>4.30.2</protobuf-java.version>
+		<spring-grpc.version>0.9.0</spring-grpc.version>
+		<jjwt.version>0.12.6</jjwt.version>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-oauth2-authorization-server</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-security</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.security</groupId>
+			<artifactId>spring-security-crypto</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.bouncycastle</groupId>
+			<artifactId>bcprov-jdk18on</artifactId>
+			<version>1.81</version>
+		</dependency>
+		<dependency>
+			<groupId>io.grpc</groupId>
+			<artifactId>grpc-services</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.grpc</groupId>
+			<artifactId>spring-grpc-server-web-spring-boot-starter</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>io.jsonwebtoken</groupId>
+			<artifactId>jjwt-api</artifactId>
+			<version>${jjwt.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>io.jsonwebtoken</groupId>
+			<artifactId>jjwt-impl</artifactId>
+			<version>${jjwt.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>io.jsonwebtoken</groupId>
+			<artifactId>jjwt-jackson</artifactId>
+			<version>${jjwt.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springdoc</groupId>
+			<artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
+			<version>2.8.9</version>
+		</dependency>
+
+
+		<dependency>
+			<groupId>org.postgresql</groupId>
+			<artifactId>postgresql</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.grpc</groupId>
+			<artifactId>spring-grpc-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.security</groupId>
+			<artifactId>spring-security-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.grpc</groupId>
+				<artifactId>spring-grpc-dependencies</artifactId>
+				<version>${spring-grpc.version}</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<configuration>
+					<annotationProcessorPaths>
+						<path>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+						</path>
+						<path>
+							<groupId>org.springframework.boot</groupId>
+							<artifactId>spring-boot-configuration-processor</artifactId>
+						</path>
+					</annotationProcessorPaths>
+				</configuration>
+			</plugin>
+			<!-- <plugin>
+				<groupId>io.github.ascopes</groupId>
+				<artifactId>protobuf-maven-plugin</artifactId>
+				<version>3.4.2</version>
+				<configuration>
+					<protocVersion>${protobuf-java.version}</protocVersion>
+					<binaryMavenPlugins>
+						<binaryMavenPlugin>
+							<groupId>io.grpc</groupId>
+							<artifactId>protoc-gen-grpc-java</artifactId>
+							<version>${grpc.version}</version>
+							<options>@generated=omit</options>
+						</binaryMavenPlugin>
+					</binaryMavenPlugins>
+				</configuration>
+				<executions>
+					<execution>
+						<id>generate</id>
+						<goals>
+							<goal>generate</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin> -->
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<configuration>
+					<excludes>
+						<exclude>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+						</exclude>
+					</excludes>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

src/main/java/com/example/app/AppApplication.java

@@ -0,0 +1,13 @@
+package com.example.app;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class AppApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(AppApplication.class, args);
+	}
+
+}

src/main/java/com/example/app/configurations/DataSourceConfiguration.java

@@ -0,0 +1,17 @@
+package com.example.app.configurations;
+
+import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+
+@Configuration(proxyBeanMethods = false)
+public class DataSourceConfiguration {
+    @Bean
+    @Primary
+    @ConfigurationProperties("app.datasource")
+    public DataSourceProperties dataSourceProperties() {
+        return new DataSourceProperties();
+    }
+}

src/main/java/com/example/app/configurations/PasswordEncoderConfiguration.java

@@ -0,0 +1,14 @@
+package com.example.app.configurations;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.crypto.argon2.Argon2PasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+
+@Configuration
+public class PasswordEncoderConfiguration {
+    @Bean
+    public static PasswordEncoder passwordEncoder() {
+        return Argon2PasswordEncoder.defaultsForSpringSecurity_v5_8();
+    }
+}

src/main/java/com/example/app/configurations/SecurityConfiguration.java

@@ -0,0 +1,64 @@
+package com.example.app.configurations;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.ProviderManager;
+import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.http.SessionCreationPolicy;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.SecurityFilterChain;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+import com.example.app.filters.JwtAuthFilter;
+
+import lombok.RequiredArgsConstructor;
+
+@Configuration
+@EnableWebSecurity
+@RequiredArgsConstructor
+public class SecurityConfiguration {
+    private final JwtAuthFilter jwtAuthFilter;
+    private final UserDetailsService userDetailsService;
+    private final PasswordEncoder passwordEncoder;
+
+    @Bean
+    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
+        http
+                // Disable CSRF (not needed for stateless JWT)
+                .csrf(csrf -> csrf.disable())
+
+                // Configure endpoint authorization
+                .authorizeHttpRequests(auth -> auth
+                        .requestMatchers("/users/auth", "/users", "/docs/**",
+                                "/v3/api-docs")
+                        .permitAll()
+
+                        .requestMatchers("/auth/user/**").hasAuthority("ROLE_USER")
+                        .requestMatchers("/auth/admin/**").hasAuthority("ROLE_ADMIN")
+
+                        .anyRequest().authenticated())
+
+                // Stateless session (required for JWT)
+                .sessionManagement(sess -> sess.sessionCreationPolicy(SessionCreationPolicy.STATELESS))
+
+                // Add JWT filter before Spring Security's default filter
+                .addFilterBefore(jwtAuthFilter, UsernamePasswordAuthenticationFilter.class);
+
+        return http.build();
+    }
+
+    /*
+     * Authentication manager bean
+     * Required for programmatic authentication (e.g., in /generateToken)
+     */
+    @Bean
+    public AuthenticationManager authenticationManager() throws Exception {
+        DaoAuthenticationProvider authenticationProvider = new DaoAuthenticationProvider(userDetailsService);
+        authenticationProvider.setPasswordEncoder(passwordEncoder);
+        return new ProviderManager(authenticationProvider);
+    }
+}

src/main/java/com/example/app/controllers/UserAccountController.java

@@ -0,0 +1,30 @@
+package com.example.app.controllers;
+
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.example.app.dtos.UserAccountCreationDto;
+import com.example.app.services.UserAccountService;
+
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequestMapping("/users")
+@RequiredArgsConstructor
+public class UserAccountController {
+    private final UserAccountService userAccountService;
+
+    @PostMapping
+    public Long save(@RequestBody UserAccountCreationDto dto) {
+        return userAccountService.save(dto).getId();
+    }
+
+    @DeleteMapping("/{id}")
+    public void deleteById(@PathVariable Long id) {
+        userAccountService.deleteById(id);
+    }
+}

src/main/java/com/example/app/controllers/UserAuthController.java

@@ -0,0 +1,38 @@
+package com.example.app.controllers;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.example.app.dtos.JwtRequestDto;
+import com.example.app.mappers.JwtRequestMapper;
+import com.example.app.misc.JwtRequest;
+import com.example.app.services.JwtService;
+
+@RestController
+@RequestMapping("/users/auth")
+public class UserAuthController {
+    @Autowired
+    private JwtService jwtService;
+    @Autowired
+    private AuthenticationManager authenticationManager;
+    @Autowired
+    JwtRequestMapper mapper;
+
+    @PostMapping()
+    public String authenticateAndGetToken(@RequestBody JwtRequestDto dto) {
+        JwtRequest jwtRequest = mapper.fromDto(dto);
+        Authentication authentication = authenticationManager.authenticate(
+                new UsernamePasswordAuthenticationToken(jwtRequest.getUsername(), jwtRequest.getPassword()));
+        if (authentication.isAuthenticated()) {
+            return jwtService.generateToken(jwtRequest.getUsername());
+        }
+        throw new UsernameNotFoundException("Invalid user request");
+    }
+}

src/main/java/com/example/app/dtos/JwtRequestDto.java

@@ -0,0 +1,11 @@
+package com.example.app.dtos;
+
+import lombok.Getter;
+import lombok.ToString;
+
+@Getter
+@ToString
+public class JwtRequestDto {
+    private String email;
+    private String password;
+}

src/main/java/com/example/app/dtos/UserAccountCreationDto.java

@@ -0,0 +1,13 @@
+package com.example.app.dtos;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+
+@Builder
+@Getter
+@AllArgsConstructor
+public class UserAccountCreationDto {
+    private final String email;
+    private final String password;
+}

src/main/java/com/example/app/dtos/UserAccountDto.java

@@ -0,0 +1,14 @@
+package com.example.app.dtos;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.Setter;
+
+@Builder
+@Getter
+@Setter
+@AllArgsConstructor
+public class UserAccountDto {
+    private String email;
+}

src/main/java/com/example/app/entities/Role.java

@@ -0,0 +1,31 @@
+package com.example.app.entities;
+
+import java.util.Set;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToMany;
+import jakarta.persistence.Table;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Table(name = "roles")
+@Builder
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class Role {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+    @Column(name = "name", nullable = false, unique = true)
+    private String name;
+    @ManyToMany(mappedBy = "roles")
+    private Set<UserAccount> userAccounts;
+}

src/main/java/com/example/app/entities/UserAccount.java

@@ -0,0 +1,40 @@
+package com.example.app.entities;
+
+import java.util.Set;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.JoinTable;
+import jakarta.persistence.ManyToMany;
+import jakarta.persistence.Table;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import lombok.ToString;
+
+@Table(name = "user_accounts")
+@Entity
+@Builder
+@Getter
+@Setter
+@ToString
+@NoArgsConstructor
+@AllArgsConstructor
+public class UserAccount {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+    @Column(name = "email", nullable = false, unique = true)
+    private String email;
+    @Column(name = "password_hash", nullable = false)
+    private String passwordHash;
+    @ManyToMany
+    @JoinTable(name = "user_account_roles", joinColumns = @JoinColumn(name = "user_id"), inverseJoinColumns = @JoinColumn(name = "role_id"))
+    private Set<Role> roles;
+}

src/main/java/com/example/app/filters/JwtAuthFilter.java

@@ -0,0 +1,51 @@
+package com.example.app.filters;
+
+import java.io.IOException;
+import java.util.Optional;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
+import org.springframework.stereotype.Component;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import com.example.app.services.JwtService;
+
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+@Component
+public class JwtAuthFilter extends OncePerRequestFilter {
+    @Autowired
+    private UserDetailsService userDetailsService;
+    @Autowired
+    private JwtService jwtService;
+
+    @Override
+    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
+            throws IOException, ServletException {
+        final Optional<String> authHeader = Optional.ofNullable(request.getHeader("Authorization"));
+        Optional<String> token = authHeader
+                .filter(x -> x.startsWith("Bearer "))
+                .map(x -> x.substring(7));
+        Optional<String> username = token.flatMap(x -> jwtService.extractUsername(x));
+
+        if (username.isPresent()
+                && Optional.ofNullable(SecurityContextHolder.getContext().getAuthentication()).isEmpty()) {
+            UserDetails userDetails = userDetailsService.loadUserByUsername(username.get());
+            if (jwtService.validateToken(token.get(), userDetails)) {
+                UsernamePasswordAuthenticationToken authToken = new UsernamePasswordAuthenticationToken(userDetails,
+                        null, userDetails.getAuthorities());
+                authToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
+                SecurityContextHolder.getContext().setAuthentication(authToken);
+            }
+        }
+
+        filterChain.doFilter(request, response);
+    }
+}

src/main/java/com/example/app/mappers/JwtRequestMapper.java

@@ -0,0 +1,20 @@
+package com.example.app.mappers;
+
+import org.springframework.stereotype.Component;
+
+import com.example.app.dtos.JwtRequestDto;
+import com.example.app.misc.JwtRequest;
+
+@Component
+public class JwtRequestMapper implements Mapper<JwtRequest, JwtRequestDto> {
+    @Override
+    public JwtRequest fromDto(JwtRequestDto dto) {
+        return JwtRequest.builder().username(dto.getEmail()).password(dto.getPassword()).build();
+    }
+
+    @Override
+    public JwtRequestDto toDto(JwtRequest entity) {
+        throw new UnsupportedOperationException("Unimplemented method 'toDto'");
+    }
+
+}

src/main/java/com/example/app/mappers/Mapper.java

@@ -0,0 +1,7 @@
+package com.example.app.mappers;
+
+public interface Mapper<E, D> {
+    public E fromDto(D dto);
+
+    public D toDto(E entity);
+}

src/main/java/com/example/app/mappers/UserAccountCreationMapper.java

@@ -0,0 +1,32 @@
+package com.example.app.mappers;
+
+import org.springframework.stereotype.Component;
+
+import com.example.app.dtos.UserAccountCreationDto;
+import com.example.app.entities.UserAccount;
+
+import lombok.RequiredArgsConstructor;
+
+import org.springframework.security.crypto.password.PasswordEncoder;
+
+@Component
+@RequiredArgsConstructor
+public class UserAccountCreationMapper implements Mapper<UserAccount, UserAccountCreationDto> {
+    private final PasswordEncoder passwordEncoder;
+
+    @Override
+    public UserAccount fromDto(UserAccountCreationDto dto) {
+        return UserAccount
+                .builder()
+                .id(null)
+                .email(dto.getEmail())
+                .passwordHash(passwordEncoder.encode(dto.getPassword()))
+                .build();
+    }
+
+    @Override
+    public UserAccountCreationDto toDto(UserAccount entity) {
+        throw new UnsupportedOperationException("Unimplemented method 'toDto'");
+    }
+
+}

src/main/java/com/example/app/mappers/UserAccountMapper.java

@@ -0,0 +1,20 @@
+package com.example.app.mappers;
+
+import org.springframework.stereotype.Component;
+
+import com.example.app.dtos.UserAccountDto;
+import com.example.app.entities.UserAccount;
+
+@Component
+public class UserAccountMapper implements Mapper<UserAccount, UserAccountDto> {
+
+    @Override
+    public UserAccount fromDto(UserAccountDto dto) {
+        throw new UnsupportedOperationException("Unimplemented method 'fromDto'");
+    }
+
+    @Override
+    public UserAccountDto toDto(UserAccount entity) {
+        return UserAccountDto.builder().email(entity.getEmail()).build();
+    }
+}

src/main/java/com/example/app/misc/JwtRequest.java

@@ -0,0 +1,13 @@
+package com.example.app.misc;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+
+@Builder
+@Getter
+@AllArgsConstructor
+public class JwtRequest {
+    private String username;
+    private String password;
+}

src/main/java/com/example/app/repositories/UserAccountRepository.java

@@ -0,0 +1,11 @@
+package com.example.app.repositories;
+
+import java.util.Optional;
+
+import org.springframework.data.repository.CrudRepository;
+
+import com.example.app.entities.UserAccount;
+
+public interface UserAccountRepository extends CrudRepository<UserAccount, Long> {
+    public Optional<UserAccount> findByEmail(String email);
+}

src/main/java/com/example/app/services/JwtService.java

@@ -0,0 +1,77 @@
+package com.example.app.services;
+
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+import java.util.function.Function;
+
+import javax.crypto.SecretKey;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.stereotype.Service;
+
+import io.jsonwebtoken.Claims;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.io.Decoders;
+import io.jsonwebtoken.security.Keys;
+import lombok.Getter;
+
+@Getter
+@Service
+public class JwtService {
+    @Value("${SECRET}")
+    private String SECRET;
+
+    public String generateToken(String username) {
+        Map<String, Object> claims = new HashMap<>();
+        return generateToken(claims, username);
+    }
+
+    private String generateToken(Map<String, Object> claims, String username) {
+        return Jwts
+                .builder()
+                .claims(claims)
+                .subject(username)
+                .issuedAt(new Date())
+                .expiration(new Date(System.currentTimeMillis() + 1000 * 60 * 30))
+                .signWith(getSignKey())
+                .compact();
+    }
+
+    private SecretKey getSignKey() {
+        byte[] keyBytes = Decoders.BASE64.decode(SECRET);
+        return Keys.hmacShaKeyFor(keyBytes);
+    }
+
+    public Optional<String> extractUsername(String token) {
+        return extractClaim(token, Claims::getSubject);
+    }
+
+    public Optional<Date> extractExpiration(String token) {
+        return extractClaim(token, Claims::getExpiration);
+    }
+
+    public <T> Optional<T> extractClaim(String token, Function<Claims, T> claimResolver) {
+        final Claims claims = extractAllClaims(token);
+        return Optional.ofNullable(claimResolver.apply(claims));
+    }
+
+    private Claims extractAllClaims(String token) {
+        return Jwts
+                .parser()
+                .verifyWith(getSignKey())
+                .build()
+                .parseSignedClaims(token)
+                .getPayload();
+    }
+
+    private boolean isTokenExpired(String token) {
+        return extractExpiration(token).map(x -> x.before(new Date())).orElse(false);
+    }
+
+    public boolean validateToken(String token, UserDetails user) {
+        return extractUsername(token).map(x -> x.equals(user.getUsername())).orElse(false) && !isTokenExpired(token);
+    }
+}

src/main/java/com/example/app/services/UserAccountDetails.java

@@ -0,0 +1,60 @@
+package com.example.app.services;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.UserDetails;
+
+import com.example.app.entities.Role;
+import com.example.app.entities.UserAccount;
+
+public class UserAccountDetails implements UserDetails {
+    private String email;
+    private String passwordHash;
+    private List<GrantedAuthority> authorities;
+
+    public UserAccountDetails(UserAccount userAccount) {
+        this.email = userAccount.getEmail();
+        this.passwordHash = userAccount.getPasswordHash();
+        this.authorities = userAccount.getRoles().stream().map(Role::getName).map(SimpleGrantedAuthority::new)
+                .collect(Collectors.toList());
+    }
+
+    @Override
+    public Collection<? extends GrantedAuthority> getAuthorities() {
+        return authorities;
+    }
+
+    @Override
+    public String getUsername() {
+        return email;
+    }
+
+    @Override
+    public String getPassword() {
+        return passwordHash;
+    }
+
+    @Override
+    public boolean isAccountNonExpired() {
+        return true;
+    }
+
+    @Override
+    public boolean isAccountNonLocked() {
+        return true;
+    }
+
+    @Override
+    public boolean isCredentialsNonExpired() {
+        return true;
+    }
+
+    @Override
+    public boolean isEnabled() {
+        return true;
+    }
+}

src/main/java/com/example/app/services/UserAccountService.java

@@ -0,0 +1,36 @@
+package com.example.app.services;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+
+import com.example.app.dtos.UserAccountCreationDto;
+import com.example.app.entities.UserAccount;
+import com.example.app.mappers.UserAccountCreationMapper;
+import com.example.app.repositories.UserAccountRepository;
+
+@Service
+public class UserAccountService implements UserDetailsService {
+    @Autowired
+    private UserAccountRepository repository;
+    @Autowired
+    private UserAccountCreationMapper mapper;
+
+    public UserAccount save(UserAccountCreationDto dto) {
+        final UserAccount user = mapper.fromDto(dto);
+        return repository.save(user);
+    }
+
+    public void deleteById(Long id) {
+        repository.deleteById(id);
+    }
+
+    @Override
+    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
+        return repository.findByEmail(username).map(UserAccountDetails::new).orElseThrow(
+                () -> new UsernameNotFoundException(String.format("User of `email=%s` not found", username)));
+    }
+
+}

src/main/resources/application.properties

@@ -0,0 +1,5 @@
+spring.application.name=app
+spring.jpa.hibernate.ddl-auto=update
+springdoc.swagger-ui.path=/docs/swagger-ui.html
+springdoc.api-docs.path=/docs/api-docs
+app.datasource.url=${DATASOURCE_URL}

src/test/java/com/example/app/AppApplicationTests.java

@@ -0,0 +1,13 @@
+package com.example.app;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class AppApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}