configure jOOQ code-generation to generate nullability annotations

Author: ThoSap

README.md

@@ -286,6 +286,17 @@ make generate-jooq
 ./gradlew :generated:jooqCodegen
 ```
 
+The generator writes JSpecify nullability annotations into the generated sources, so NullAway reads the real nullness of every generated method instead of guessing.  
+Two consequences are worth knowing:
+
+- jOOQ does not officially support the `TYPE_USE` positioning that JSpecify requires yet ([jOOQ/jOOQ#10759](https://github.com/jOOQ/jOOQ/issues/10759)).  
+  The positioning is correct here only because the generated code uses no generics, collections, maps, arrays or forced types with inner
+  classes.  
+  Keep the `includes` list free of such objects, or review the annotation positions after a regeneration.
+- Every generated class carries `@SuppressWarnings({"all", ...})`, which Error Prone honours.  
+  That suppression, and nothing else, is why the generated sources are exempt from the checks in  `errorprone.args`, including `RequireExplicitNullMarking`.  
+  Do not add `NullAway:TreatGeneratedAsUnannotated`: it would make NullAway discard the nullability annotations that this generator now writes.
+
 ### Docker Environment
 
 See [Docker Environment](docs/docker-environment.md) for setting up a local development environment using Quarkus Dev Services.

generated/build.gradle.kts

@@ -9,6 +9,7 @@ dependencies {
      */
     api(libs.jooq)
     compileOnly(libs.jooqMeta)
+    compileOnlyApi(libs.jspecify)
     // PostgreSQL JDBC Driver for jOOQ generation
     jooqCodegen(libs.postgresql)
 }
@@ -49,6 +50,14 @@ jooq {
                 fluentSetters = true
                 generatedAnnotation = true
                 pojos = false
+                nonnullAnnotation = true
+                nullableAnnotation = true
+                // We use JSpecify annotations already even though jOOQ does not officially support JSpecify's TYPE_USE positioning yet.
+                // See https://github.com/jOOQ/jOOQ/issues/10759
+                // This only works as our generated code is not using any generics, collections, maps, arrays
+                // or forced types with inner classes, and therefore the positioning of the annotations is accidentally correct.
+                nonnullAnnotationType = "org.jspecify.annotations.NonNull"
+                nullableAnnotationType = "org.jspecify.annotations.Nullable"
             }
             target {
                 packageName = "it.aboutbits.postgresql.core.infrastructure.persistence"