Upgrading to Spring Boot 3 causing annotation processing errors

Upgrading to Spring Boot 3 can sometimes lead to annotation processing errors, especially if your project includes outdated dependencies or unsupported configurations. This article provides multiple solutions to address the issue, along with possible causes and fixes.

Common Causes for Annotation Processing Errors

1. Deprecated or Removed Classes/Methods: Classes or methods used in your code may have been modified or removed in Spring Boot 3.
2. Dependency Compatibility: Libraries in your pom.xml might not be compatible with Spring Boot 3.
3. Lombok Configuration Issues: Lombok versions or configurations may cause conflicts during annotation processing.
4. Reflection Metadata: Annotation processing may fail due to stricter reflection handling in Spring Boot 3.

Solutions to Resolve Annotation Processing Errors

Solution 1: Update Imports and Dependencies

Errors might occur due to changes in class or method paths after upgrading. Follow these steps:

• Remove conflicting imports: If certain classes (e.g., ResultBuilder, getRuleName()) aren’t resolving, delete their import statements. Let your IDE re-import the correct classes automatically.
• Check pom.xml dependencies: Verify if the libraries providing these classes/methods are compatible with Spring Boot 3. Update to compatible versions if needed.
• Verify Lombok: Ensure that Lombok’s version is compatible (discussed in Solution 2).

Solution 2: Fix Lombok Dependency

Annotation processing errors are often related to Lombok configuration. Update your pom.xml as follows:

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.18.24</version> <!-- Use the latest version -->
    <scope>provided</scope>
</dependency>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>11</source> 
                <target>11</target>
                <annotationProcessorPaths>
                    <path>
                        <groupId>org.projectlombok</groupId>
                        <artifactId>lombok</artifactId>
                        <version>${lombok.version}</version>
                    </path>
                </annotationProcessorPaths>
            </configuration>
        </plugin>
    </plugins>
</build>

Replace <version> and <source>/<target> with versions compatible with your project.

Solution 3: Upgrade SpringDoc Version

If you’re using SpringDoc and experiencing errors, update its version:

<springdoc.version>1.8.0</springdoc.version>

This update resolved annotation errors for many users, though it may introduce new issues. Be prepared to address those as they arise.

Solution 4: Enable Reflection Metadata

Spring Boot 3 disables reflection by default, which may cause annotation processing errors. Modify your Maven configuration:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>${maven-compiler-plugin.version}</version>
    <configuration>
        <source>${java.version}</source>
        <target>${java.version}</target>
        <parameters>true</parameters> <!-- Enable reflection metadata -->
        <annotationProcessorPaths>
            <path>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-configuration-processor</artifactId>
                <version>${spring-boot.version}</version>
            </path>
        </annotationProcessorPaths>
    </configuration>
</plugin>

This ensures that required metadata is generated during the build process.

Final Thoughts

Upgrading to Spring Boot 3 often brings significant changes that require adjustments to dependencies and configurations. Here’s a quick checklist to ensure a smoother transition:

1. Verify and update imports for any removed or modified classes/methods.
2. Update your dependencies in pom.xml to compatible versions.
3. Double-check Lombok settings and its compatibility.
4. Enable reflection metadata for proper annotation processing.

By following these solutions, you should be able to resolve most annotation processing errors after upgrading to Spring Boot 3.

Keywords

• Spring Boot 3 annotation processing errors
• Fix Lombok issues Spring Boot 3
• Spring Boot 3 reflection metadata
• Maven configuration Spring Boot upgrade
• Resolving Spring Boot dependency errors