Kotlin Reflection (kotlin-reflect)

Use KClass in your Kotlin-facing API so callers write MyType::class and you can read Kotlin info; convert to .java at the exact point you call into Java libraries. Store whichever the consumers key on.

starProjectedType turns a KClass into a KType where every generic parameter is replaced by a star (*), meaning 'unknown'. You use it when you have a KClass at runtime but no concrete type arguments to fill in.

A suspend function compiles to a normal method with an extra hidden Continuation parameter. Java reflection just sees that odd extra parameter; kotlin-reflect tells you it's actually suspend via isSuspend.

Use Java reflection when you don't need Kotlin-specific info, want to avoid the extra kotlin-reflect dependency and startup cost, or interop with Java frameworks. Bridge with .java and .kotlin and the jvm extension functions.

Round-tripping a class through .java and back to .kotlin gives you an equal KClass, and comparing with == works. The conversions are cheap lookups, not new copies of your data.

Each parameter of a callable is a KParameter with a kind (instance receiver, extension receiver, or value), an index, a name, a type, and flags like isOptional and isVararg. You use these to know the right order for call() or to build the map for callBy().

Loop over the class's declaredMemberProperties, call get(instance) on each to read the value, and use property.returnType for the type. Watch out for private properties (set isAccessible) and nullable values.

simpleName is the short class name; qualifiedName is the full dotted name including package. Both are nullable: anonymous objects and local classes have no real name, so they return null.

Measure first. If reflection is only used a little, cache the resolved handles. If it's on a hot path or you're size-constrained, replace it with compile-time code generation so you can drop the library entirely.

A KClass forgets the generic arguments, so it can't tell List<String> from List<Int>. KType keeps them, letting the library pick the right serializer for each element. typeOf<T>() captures that full type at the call site.