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how to create json response in spring boot java like this as shown when the following attributes are not present in json request

I am creating an controller where there is certain attributes in json which is an doing in postman a POST request like this if all attributes are posted then its fine
if one then is missing then it would look like this
i want this response when some attribute is missing how to implement this

This is normally implemented in two steps:
Implement a validation mechanism for the method that handles the incoming request. Normally you would throw an exception here if the input is incorrect, in your example a missing JSON key.
Implement a global error handler that will process the exception from point 1 and format the response as JSON.
For point 1 the usual choice is the Java Bean Validation framework because it's integrated with Spring Boot and allows to define validation constraints with annotations like #NotEmpty. You can take a look at this example.
For point 2 the usual choice is #RestControllerAdvice or #ControllerAdvice. You would have to understand your service web server setup to implement it properly e.g. it might behave differently if you use Spring WebFlux.

Spring MVC: get content negotiation result in a #ExceptionHandler

I want to write an #ExceptionHandler so JSON requests will get an error response in JSON as well. For non-JSON requests, I want the servlet container to send its default HTML response.
To do this, I'll need to do some content negotiation. Spring MVC handles it for normal requests via annotations, but no such annotation is available for #ExceptionHandlers.
I am wondering how can I programmatically call the content negotiation code?

So apparently, content negotiation happens after the error handler is called, so I have to do most of the heavy lifting myself.
The method to use is ContentNegotiationManager.resolveMediaTypes(), which gives a list of types that one will have to go through and make a decision.
An example of how to do this can be found the source of ContentNegotiatingViewResolver.getMediaTypes()

Spring MVC like processing of AMQP messages

What I want to do is process AMQP messages in a very similar way the Http Requests are processed using spring-webmvc annotations such as #RequestMapping, #RequestParam etc. But, instead of the Http Request my source object will be an AMQP message. The AMQP message request will have two headers, for example -
method="POST"
url="/api/myobjects/{someParam}"
and the payload will contain data in json format.
If you have noticed, this is nothing but HTTP REST api mapped to AMQP message.
I want to be able to write a controller like handler, for example -
#Controller
public class MyObjectHandler {
#RequestMapping(value="/api/myobjects/{someParam}", method="POST")
public MyObject createMyObject(#Payload MyObject myObj, #PathParam String someParam) {
//... some processing
return myObj;
}
// ...more handlers
}
I have looked at spring-amqp/rabbitmq annotations and also spring integration annotations. They are close to what I want, but would not allow routing to handler methods based on header parameters, especially the REST url.
I don't expect that a readymade solution would be available for this. Just want to make sure I choose the best possible option. Some of the options I think are (in order of precedence)
If the spring-webmvc annotation processing mechanism is extensible, just extend it to use AMQP message as source instead of Http Request
Modify the spring-webmvc annotation processing mechanism to take the AMQP message as input instead of Http Request
Write your own solution with custom annotaions and their processors, which I think is a very involving task
Or any other possible approach than above?
Any guidance/direction is appreciated.

I think the starting point is likely AbstractMethodMessageHandler in spring-messaging.
There's currently a SimpAnnotationMethodMessageHandler implementation for websockets which invokes #Controllers.
You could use a #RabbisListener method that has a Message<?> parameter (Spring AMQP will convert the underlying Rabbit message to a spring-messaging message, including the headers). Then, invoke the message handler to route to the appropriate controller method.
If you come up with a robust implementation, please consider contributing it.

Apache Camel - http Producer don't use GET-Method with enrich Pattern

I have a RESTful Webservice which I want to use with a content enricher in a Camel-Route.
See this similar Code:
from("direct:in") // Here comes XML
.to("validator:something.xsd") // validate it
.unmarshal("something-jaxb") // put it into a POJO
.setHeader(Exchange.HTTP_URI, simple("http://localhost:12345/restws/${header.foo}")) // Create the dynamic URI with simple
.setHeader(Exchange.HTTP_METHOD, constant("GET")) // set the HTTP-Method to use
.enrich("http://dummy", new MyAggregator()) // fetch some Information from a Restful Webservice
.to("direct:out"); // send the Message to another route
If I run this, I get the following error:
No type converter available to convert from type: de.my.Class to the required type: java.io.InputStream with value de.my.Class#620ee765.
It seems to me, he tries to send the body of the Exchange to the http-Endpoint, although I set the HTTP-Method to GET. I've read the documentation (https://camel.apache.org/http.html) and below Calling using GET or POST it describes that the Algorithm which selects the Method first look at the Header (1. Use method provided in header).
I found some workarounds, which describes how to move the body to a Exchange-property and move it back again after the Webservice-Call, but this can't be it...
EDIT:
Like Claus Ibsen mentioned enrich doesn't support dynamic uris. Fixed this in the example!

Neither enrich nor pollEnrich supports dynamic uris for their endpoints. Instead of using enrich, you can use the recipient list which support dynamic uris, and the aggregation strategy as well.

If it's "full of lists" of resources, sounds like you would want to split the lists and do a get on each resource

What's in the pojo? Your GET parameter should be a resource identifier and query parameters. That requires a custom converter.
http://fusesource.com/docs/esb/4.2/rest/RESTIntro.html
maybe consider using restlet instead... it's easier I think.
http://camel.apache.org/restlet.html

JAX-RS: retrieve alternate format based on URL pattern

I have a simple JAX-RS service running in a Tomcat 6 container. Is it possible to display not only text but XML in the browser, in a comparable manner as in Rails by appending .xml or .json?
The service I have is based on this tutorial.

Short answer is no, JAX-RS does not allow you to switch the response content type simply by appending 'xml' or 'json' to the URL.
The specification explicitly defines how content negotiation happens - via the Accept HTTP header from the client side, matching with the #Produces annotation on the server side. So going by the spec, if you want to get a different content type then you would specify as such in an Accept header, and that content type would be returned (as long as the server supports it).
Having said that, JAX-RS implementations are free to implement custom (non-portable) extensions to support behavior similar to what you describe. An example would be RESTEasy, which allows you to define the desired content type as a query parameter Section 17.2 - Query String Parameter-based negotiation.
You could also design your resource classes to easily support the desired behavior - some examples can be seen in the Apache CXF Content Negotiation guide.