Throw an exception if nothing is set in the @Schema annotation field

[uc4w6c]

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Describe the bug

An exception will be thrown if no field is set in the @Schema annotation or if only the default value is set.
(default value example: @Schema(maxLength = Integer.MAX_VALUE))

example

@GetMapping
public String index(@RequestParam @Schema String id) {
  return null;
}

log

java.lang.NullPointerException: Cannot invoke "io.swagger.v3.oas.annotations.media.ArraySchema.schema()" because the return value of "io.swagger.v3.oas.annotations.Parameter.array()" is null
	at org.springdoc.core.service.GenericParameterService.setSchema(GenericParameterService.java:338) ~[springdoc-openapi-starter-common-2.1.0.jar:2.1.0]
	at org.springdoc.core.service.GenericParameterService.buildParameterFromDoc(GenericParameterService.java:299) ~[springdoc-openapi-starter-common-2.1.0.jar:2.1.0]
	at org.springdoc.core.service.AbstractRequestService.build(AbstractRequestService.java:321) ~[springdoc-openapi-starter-common-2.1.0.jar:2.1.0]
	at org.springdoc.api.AbstractOpenApiResource.calculatePath(AbstractOpenApiResource.java:474) ~[springdoc-openapi-starter-common-2.1.0.jar:2.1.0]
	at org.springdoc.api.AbstractOpenApiResource.calculatePath(AbstractOpenApiResource.java:654) ~[springdoc-openapi-starter-common-2.1.0.jar:2.1.0]
	at org.springdoc.webmvc.api.OpenApiResource.lambda$calculatePath$11(OpenApiResource.java:219) ~[springdoc-openapi-starter-webmvc-api-2.1.0.jar:2.1.0]
	at java.base/java.util.Optional.ifPresent(Optional.java:178) ~[na:na]
	at org.springdoc.webmvc.api.OpenApiResource.calculatePath(OpenApiResource.java:200) ~[springdoc-openapi-starter-webmvc-api-2.1.0.jar:2.1.0]
	at org.springdoc.webmvc.api.OpenApiResource.lambda$getPaths$2(OpenApiResource.java:170) ~[springdoc-openapi-starter-webmvc-api-2.1.0.jar:2.1.0]
	at java.base/java.util.Optional.ifPresent(Optional.java:178) ~[na:na]
	at org.springdoc.webmvc.api.OpenApiResource.getPaths(OpenApiResource.java:149) ~[springdoc-openapi-starter-webmvc-api-2.1.0.jar:2.1.0]
	at org.springdoc.api.AbstractOpenApiResource.getOpenApi(AbstractOpenApiResource.java:334) ~[springdoc-openapi-starter-common-2.1.0.jar:2.1.0]
	at org.springdoc.webmvc.api.OpenApiResource.openapiJson(OpenApiResource.java:124) ~[springdoc-openapi-starter-webmvc-api-2.1.0.jar:2.1.0]
	at org.springdoc.webmvc.api.OpenApiWebMvcResource.openapiJson(OpenApiWebMvcResource.java:111) ~[springdoc-openapi-starter-webmvc-api-2.1.0.jar:2.1.0]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77) ~[na:na]
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
	at java.base/java.lang.reflect.Method.invoke(Method.java:568) ~[na:na]
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:207) ~[spring-web-6.0.6.jar:6.0.6]
	at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:152) ~[spring-web-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:884) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1081) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:974) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1011) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:705) ~[tomcat-embed-core-10.1.5.jar:6.0]
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.0.6.jar:6.0.6]
	at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:814) ~[tomcat-embed-core-10.1.5.jar:6.0]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:223) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-6.0.6.jar:6.0.6]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.6.jar:6.0.6]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-6.0.6.jar:6.0.6]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.6.jar:6.0.6]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.0.6.jar:6.0.6]
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.0.6.jar:6.0.6]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:185) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:158) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:177) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:119) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:400) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:859) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1734) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-10.1.5.jar:10.1.5]
	at java.base/java.lang.Thread.run(Thread.java:833) ~[na:na]

To Reproduce
Steps to reproduce the behavior:

• What version of spring-boot you are using? 2.7.10, 3.0.5
• What modules and versions of springdoc-openapi are you using? v1.6.15, v2.1.0
• What is the actual and the expected result using OpenAPI Description (yml or json)?
• Provide with a sample code (HelloController) or Test that reproduces the problem

Expected behavior

• A clear and concise description of what you expected to happen.
• What is the expected result using OpenAPI Description (yml or json)?

Screenshots
If applicable, add screenshots to help explain your problem.

Additional context
Add any other context about the problem here.