How to program to create a map schema using springdoc - springdoc

Question

I want to get a map schema in components, e.g.
components:
schemas:
Response:
type: object
additionalProperties:
type: string
Here is my code:
#Bean
public OpenAPI customOpenAPI() {
MapSchema mySchema = new MapSchema();
mySchema.setAdditionalProperties(new StringSchema());
return new OpenAPI().components(new Components()
.addSchemas("Response", mySchema)
);
}
But it will raise an exception:
{"timestamp":"2022-11-24 14:23:54.686","component":"","level":"WARN","thread-id":"http-nio-8080-exec-1","logger":"org.springdoc.core.OpenAPIService","message":"Json Processing Exception occurred: Cannot deserialize value of type `java.lang.Boolean` from Object value (token `JsonToken.START_OBJECT`)
at [Source: UNKNOWN; byte offset: #UNKNOWN] (through reference chain: io.swagger.v3.oas.models.OpenAPI["components"]->io.swagger.v3.oas.models.Components["schemas"]->java.util.LinkedHashMap["Response"])"}
{"timestamp":"2022-11-24 14:23:54.711","component":"","level":"ERROR","thread-id":"http-nio-8080-exec-1","logger":"org.apache.catalina.core.ContainerBase.[Tomcat].[localhost].[/].[dispatcherServlet]","message":"Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause"}
java.lang.NullPointerException: null
at java.base/java.util.Objects.requireNonNull(Objects.java:208)
at org.springdoc.core.OpenAPIService.buildOpenAPIWithOpenAPIDefinition(OpenAPIService.java:520)
at org.springdoc.core.OpenAPIService.build(OpenAPIService.java:259)
at org.springdoc.api.AbstractOpenApiResource.getOpenApi(AbstractOpenApiResource.java:314)
at org.springdoc.webmvc.api.OpenApiResource.openapiYaml(OpenApiResource.java:156)
at org.springdoc.webmvc.api.OpenApiWebMvcResource.openapiYaml(OpenApiWebMvcResource.java:133)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
If I changed the code to
#Bean
public OpenAPI customOpenAPI() {
MapSchema mySchema = new MapSchema();
mySchema.setAdditionalProperties(false); <-- I pass a boolean value instead of a schema
return new OpenAPI().components(new Components()
.addSchemas("Response", mySchema)
);
}
SpringDoc can generate the swagger doc successfully.
components:
schemas:
Response:
type: object
additionalProperties: false
Can you help to check what's wrong with my previous code ? Thanks.
I'm using spring-boot 2.7.5 and
org.springdoc/springdoc-openapi-webmvc-core 1.6.11