Missing parameter name in MongoDB repository causing MappingException

Question

I am in the process of converting my Spring Boot application to a native image using Spring Native and GraalVM. My application uses MongoDB, and I am encountering a MappingException when the application attempts to interact with the database through the repository layer.

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: org.springframework.data.mapping.MappingException: Parameter org.springframework.data.mapping.Parameter@bf07bd2a does not have a name] with root cause

What I've tried:

• Registering my document classes and repositories in the RuntimeHintsRegistrar implementation, but this has not resolved the issue.
• Using the GraalVM native image agent to generate reflection configuration, but the problem persists.

Answer 1

I resolved a MappingException in my Spring Boot application (converted to a native image with Spring Native and GraalVM) by adding a compiler argument in the Gradle build script. This change ensured that parameter names are available at runtime, which is necessary for correct operation of frameworks that rely on parameter names for mapping purposes (like Spring Data).

Here's the specific change I made in build.gradle:

allprojects {
    gradle.projectsEvaluated {
        tasks.withType(JavaCompile) {
            ...
            options.compilerArgs << '-parameters' // Adding this line
        }
    }
}

The options.compilerArgs << '-parameters' line adds a compiler argument to include debug information about method parameter names in the compiled bytecode. This is crucial for the Spring framework, as it needs to know the names of method parameters (especially in controller methods and repositories) for proper binding and processing. By default, Java does not store formal parameter names in the compiled bytecode, so adding this compiler argument is necessary to preserve them, which in turn resolves the MappingException related to parameter name mapping in Spring Boot applications compiled with GraalVM for native images.