What problem are you trying to solve?

AddOrUpdateAnnotationAttribute can not currently add values to an array. When you try that you get

ClassCastException: class org.openrewrite.java.tree.J$NewArray cannot be cast to class org.openrewrite.java.tree.J$Literal

Describe the solution you'd like

To be able to add a value as seen here

Before

@SpringBootApplication(scanBasePackages = {"com.abc"})

After

@SpringBootApplication(scanBasePackages = {"com.abc", "com.xyz"})

Have you considered any alternatives or workarounds?

We could create a new recipe, or explicitly not allow this.
Not clear yet if we should append to existing array, or overwrite existing value.