Upgrade to Spring Boot 4.0.0

Signed-off-by: Patrick Baumgartner <contact@patbaumgartner.com>

Author: patbaumgartner

README.md

@@ -60,13 +60,13 @@ A similar setup is provided for MySQL and PostgreSQL if a persistent database co
 You can start MySQL or PostgreSQL locally with whatever installer works for your OS or use docker:
 
 ```bash
-docker run -e MYSQL_USER=petclinic -e MYSQL_PASSWORD=petclinic -e MYSQL_ROOT_PASSWORD=root -e MYSQL_DATABASE=petclinic -p 3306:3306 mysql:9.2
+docker run -e MYSQL_USER=petclinic -e MYSQL_PASSWORD=petclinic -e MYSQL_ROOT_PASSWORD=root -e MYSQL_DATABASE=petclinic -p 3306:3306 mysql:9.5
 ```
 
 or
 
 ```bash
-docker run -e POSTGRES_USER=petclinic -e POSTGRES_PASSWORD=petclinic -e POSTGRES_DB=petclinic -p 5432:5432 postgres:18.0
+docker run -e POSTGRES_USER=petclinic -e POSTGRES_PASSWORD=petclinic -e POSTGRES_DB=petclinic -p 5432:5432 postgres:18.1
 ```
 
 Further documentation is provided for [MySQL](https://github.com/spring-projects/spring-petclinic/blob/main/src/main/resources/db/mysql/petclinic_db_setup_mysql.txt)

build.gradle

@@ -1,10 +1,10 @@
 plugins {
   id 'java'
   id 'checkstyle'
-  id 'org.springframework.boot' version '4.0.0-RC2'
+  id 'org.springframework.boot' version '4.0.0'
   id 'io.spring.dependency-management' version '1.1.7'
   id 'org.graalvm.buildtools.native' version '0.11.1'
-  id 'org.cyclonedx.bom' version '3.0.0'
+  id 'org.cyclonedx.bom' version '3.0.2'
   id 'io.spring.javaformat' version '0.0.47'
   id "io.spring.nohttp" version "0.0.11"
   id 'net.ltgt.errorprone' version '4.3.0'
@@ -25,9 +25,9 @@ repositories {
   mavenCentral()
 }
 
-ext.checkstyleVersion = "11.1.0"
+ext.checkstyleVersion = "12.1.2"
 ext.springJavaformatCheckstyleVersion = "0.0.47"
-ext.webjarsLocatorLiteVersion = "1.1.1"
+ext.webjarsLocatorLiteVersion = "1.1.2"
 ext.webjarsFontawesomeVersion = "4.7.0"
 ext.webjarsBootstrapVersion = "5.3.8"
 ext.errorProneVersion = "2.42.0"
@@ -78,7 +78,6 @@ checkstyleNohttp {
 }
 
 tasks.withType(JavaCompile).configureEach {
-  options.release = 17
   options.errorprone {
     disableAllChecks = true
   }

docker-compose.yml

@@ -1,6 +1,6 @@
 services:
   mysql:
-    image: mysql:9.2
+    image: mysql:9.5
     ports:
       - "3306:3306"
     environment:
@@ -12,7 +12,7 @@ services:
     volumes:
       - "./conf.d:/etc/mysql/conf.d:ro"
   postgres:
-    image: postgres:18.0
+    image: postgres:18.1
     ports:
       - "5432:5432"
     environment:

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.0-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.1-bin.zip
 networkTimeout=10000
 validateDistributionUrl=true
 zipStoreBase=GRADLE_USER_HOME

k8s/db.yml

@@ -41,7 +41,7 @@ spec:
         app: demo-db
     spec:
       containers:
-        - image: postgres:18.0
+        - image: postgres:18.1
           name: postgresql
           env:
             - name: POSTGRES_USER

mvnw

@@ -5,7 +5,7 @@
   <parent>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-parent</artifactId>
-    <version>4.0.0-RC2</version>
+    <version>4.0.0</version>
     <relativePath></relativePath>
   </parent>
 
@@ -19,20 +19,19 @@
 
     <!-- Generic properties -->
     <java.version>25</java.version>
-    <maven.compiler.release>17</maven.compiler.release>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <!-- Important for reproducible builds. Update using e.g. ./mvnw versions:set -DnewVersion=... -->
-    <project.build.outputTimestamp>2024-11-28T14:37:52Z</project.build.outputTimestamp>
+    <project.build.outputTimestamp>2025-11-22T16:15:42Z</project.build.outputTimestamp>
 
     <!-- Web dependencies -->
-    <webjars-locator.version>1.1.1</webjars-locator.version>
+    <webjars-locator.version>1.1.2</webjars-locator.version>
     <webjars-bootstrap.version>5.3.8</webjars-bootstrap.version>
     <webjars-font-awesome.version>4.7.0</webjars-font-awesome.version>
 
-    <checkstyle.version>11.1.0</checkstyle.version>
+    <checkstyle.version>12.1.2</checkstyle.version>
     <error-prone.version>2.42.0</error-prone.version>
-    <jacoco.version>0.8.13</jacoco.version>
+    <jacoco.version>0.8.14</jacoco.version>
     <libsass.version>0.3.4</libsass.version>
     <lifecycle-mapping>1.0.0</lifecycle-mapping>
     <maven-checkstyle.version>3.6.0</maven-checkstyle.version>
@@ -290,10 +289,10 @@
         <executions>
           <execution>
             <id>default-compile</id>
-            <phase>compile</phase>
             <goals>
               <goal>compile</goal>
             </goals>
+            <phase>compile</phase>
             <configuration>
               <compilerArgs>
                 <arg>-XDcompilePolicy=simple</arg>

pom.xml

@@ -17,7 +17,6 @@
 
 import java.util.Optional;
 
-import jakarta.annotation.Nonnull;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.JpaRepository;

src/main/java/org/springframework/samples/petclinic/owner/OwnerRepository.java

@@ -33,9 +33,9 @@
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.aot.DisabledInAotMode;
 import org.springframework.web.client.RestTemplate;
-import org.testcontainers.containers.MySQLContainer;
 import org.testcontainers.junit.jupiter.Container;
 import org.testcontainers.junit.jupiter.Testcontainers;
+import org.testcontainers.mysql.MySQLContainer;
 import org.testcontainers.utility.DockerImageName;
 
 @SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
@@ -47,7 +47,7 @@ class MySqlIntegrationTests {
 
 	@ServiceConnection
 	@Container
-	static MySQLContainer<?> container = new MySQLContainer<>(DockerImageName.parse("mysql:9.2"));
+	static MySQLContainer container = new MySQLContainer(DockerImageName.parse("mysql:9.5"));
 
 	@LocalServerPort
 	int port;

src/test/java/org/springframework/samples/petclinic/MySqlIntegrationTests.java

@@ -21,7 +21,7 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Profile;
-import org.testcontainers.containers.MySQLContainer;
+import org.testcontainers.mysql.MySQLContainer;
 import org.testcontainers.utility.DockerImageName;
 
 /**
@@ -35,8 +35,8 @@ public class MysqlTestApplication {
 	@ServiceConnection
 	@Profile("mysql")
 	@Bean
-	static MySQLContainer<?> container() {
-		return new MySQLContainer<>(DockerImageName.parse("mysql:9.2"));
+	static MySQLContainer container() {
+		return new MySQLContainer(DockerImageName.parse("mysql:9.5"));
 	}
 
 	public static void main(String[] args) {