It is recommended to have an appropriate header parameter in the client request and in the server response to indicate how the entity body is serialized when transmitted over a wire.
Accept: This request header field defines a list of acceptable response formats for the response, for example,Accept: application/json,application/xmlThe
javax.ws.rs.client.WebTargetclass allows you to specify theAcceptheader via therequest()method for a JAX-RS client applicationContent-Type: This header field defines the type of the request or response message body content, for example,Content-Type: text/plain; charset=UTF-8