Support building with Java 17

Needed to remove ErrorProne and Nullaway compiler plugins

Fixes #2136

.github/workflows/gradle-build.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java: [ '25' ]
+        java: [ '17' ]
 
     steps:
       - uses: actions/checkout@v4

.github/workflows/maven-build.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        java: [ '25' ]
+        java: [ '17' ]
 
     steps:
       - uses: actions/checkout@v4

.mvn/jvm.config

@@ -1,10 +0,0 @@
---add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.model=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED
---add-exports jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED
---add-opens jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED
---add-opens jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED

.sdkmanrc

@@ -1,3 +0,0 @@
-# Enable auto-env through the sdkman_auto_env config
-# Add key=value pairs of SDKs to use below
-java=25-librca

README.md

@@ -14,7 +14,7 @@ See the presentation here:
 ## Run Petclinic locally
 
 Spring Petclinic is a [Spring Boot](https://spring.io/guides/gs/spring-boot) application built using [Maven](https://spring.io/guides/gs/maven/) or [Gradle](https://spring.io/guides/gs/gradle/).
-Java 25 or later is required for the build, but the application can run with Java 17 or newer:
+Java 17 or later is required for the build, and the application can run with Java 17 or newer:
 
 ```bash
 git clone https://github.com/spring-projects/spring-petclinic.git

build.gradle

@@ -7,7 +7,6 @@ plugins {
   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'
 }
 
 gradle.startParameter.excludedTaskNames += [ "checkFormatAot", "checkFormatAotTest" ]
@@ -17,7 +16,7 @@ version = '4.0.0-SNAPSHOT'
 
 java {
   toolchain {
-    languageVersion = JavaLanguageVersion.of(25)
+    languageVersion = JavaLanguageVersion.of(17)
   }
 }
 
@@ -30,14 +29,12 @@ ext.springJavaformatCheckstyleVersion = "0.0.47"
 ext.webjarsLocatorLiteVersion = "1.1.2"
 ext.webjarsFontawesomeVersion = "4.7.0"
 ext.webjarsBootstrapVersion = "5.3.8"
-ext.errorProneVersion = "2.42.0"
-ext.nullAwayVersion = "0.12.10"
 
 dependencies {
   implementation 'org.springframework.boot:spring-boot-starter-cache'
   implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
   implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
-  implementation 'org.springframework.boot:spring-boot-starter-webmvc'
+  implementation 'org.springframework.boot:spring-boot-starter-web'
   implementation 'org.springframework.boot:spring-boot-starter-validation'
   implementation 'javax.cache:cache-api'
   implementation 'jakarta.xml.bind:jakarta.xml.bind-api'
@@ -59,8 +56,6 @@ dependencies {
   testImplementation 'org.testcontainers:testcontainers-mysql'
   checkstyle "io.spring.javaformat:spring-javaformat-checkstyle:${springJavaformatCheckstyleVersion}"
   checkstyle "com.puppycrawl.tools:checkstyle:${checkstyleVersion}"
-  errorprone "com.google.errorprone:error_prone_core:${errorProneVersion}"
-  errorprone "com.uber.nullaway:nullaway:${nullAwayVersion}"
 }
 
 tasks.named('test') {
@@ -77,20 +72,6 @@ checkstyleNohttp {
   configFile = file('src/checkstyle/nohttp-checkstyle.xml')
 }
 
-tasks.withType(JavaCompile).configureEach {
-  options.errorprone {
-    disableAllChecks = true
-  }
-  if (name.equals("compileJava")) {
-    options.errorprone {
-      error("NullAway")
-      option("NullAway:OnlyNullMarked", "true")
-      option("NullAway:CustomContractAnnotations", "org.springframework.lang.Contract")
-      option("NullAway:JSpecifyMode", "true")
-    }
-  }
-}
-
 tasks.named("formatMain").configure { dependsOn("checkstyleMain") }
 tasks.named("formatMain").configure { dependsOn("checkstyleNohttp") }
 

pom.xml

@@ -18,11 +18,11 @@
   <properties>
 
     <!-- Generic properties -->
-    <java.version>25</java.version>
+    <java.version>17</java.version>
     <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>2025-11-22T16:15:42Z</project.build.outputTimestamp>
+    <project.build.outputTimestamp>2024-11-28T14:37:52Z</project.build.outputTimestamp>
 
     <!-- Web dependencies -->
     <webjars-locator.version>1.1.2</webjars-locator.version>
@@ -30,14 +30,13 @@
     <webjars-font-awesome.version>4.7.0</webjars-font-awesome.version>
 
     <checkstyle.version>12.1.2</checkstyle.version>
-    <error-prone.version>2.42.0</error-prone.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>
     <nohttp-checkstyle.version>0.0.11</nohttp-checkstyle.version>
-    <nullaway.version>0.12.10</nullaway.version>
     <spring-format.version>0.0.47</spring-format.version>
+
   </properties>
 
   <dependencies>
@@ -56,7 +55,7 @@
     </dependency>
     <dependency>
       <groupId>org.springframework.boot</groupId>
-      <artifactId>spring-boot-starter-webmvc</artifactId>
+      <artifactId>spring-boot-starter-web</artifactId>
     </dependency>
     <dependency>
       <groupId>org.springframework.boot</groupId>
@@ -66,6 +65,16 @@
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-thymeleaf</artifactId>
     </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-test</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-restclient</artifactId>
+      <scope>test</scope>
+    </dependency>
 
     <!-- Databases - Uses H2 by default -->
     <dependency>
@@ -114,9 +123,8 @@
     <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-devtools</artifactId>
-      <optional>true</optional>
+      <scope>test</scope>
     </dependency>
-
     <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-data-jpa-test</artifactId>
@@ -283,38 +291,6 @@
           <failOnUnableToExtractRepoInfo>false</failOnUnableToExtractRepoInfo>
         </configuration>
       </plugin>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-compiler-plugin</artifactId>
-        <executions>
-          <execution>
-            <id>default-compile</id>
-            <goals>
-              <goal>compile</goal>
-            </goals>
-            <phase>compile</phase>
-            <configuration>
-              <compilerArgs>
-                <arg>-XDcompilePolicy=simple</arg>
-                <arg>--should-stop=ifError=FLOW</arg>
-                <arg>-Xplugin:ErrorProne -XepDisableAllChecks -Xep:NullAway:ERROR -XepOpt:NullAway:OnlyNullMarked=true -XepOpt:NullAway:CustomContractAnnotations=org.springframework.lang.Contract -XepOpt:NullAway:JSpecifyMode=true</arg>
-              </compilerArgs>
-              <annotationProcessorPaths>
-                <path>
-                  <groupId>com.google.errorprone</groupId>
-                  <artifactId>error_prone_core</artifactId>
-                  <version>${error-prone.version}</version>
-                </path>
-                <path>
-                  <groupId>com.uber.nullaway</groupId>
-                  <artifactId>nullaway</artifactId>
-                  <version>${nullaway.version}</version>
-                </path>
-              </annotationProcessorPaths>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
       <!-- Spring Boot Actuator displays sbom-related information if a CycloneDX SBOM file is
       present at the classpath -->
       <plugin>