Consider the following statements: String s1 = new ObjectMapper().writeValueAsString(null); String s2 = new ObjectMapper().writeValueAsString(NullNode.getInstance()); In both the cases, serialized values s1 and s2 would be “null” (in String format). Jackson, by default, serializes null objects without any exception. What are the cases where we need to use NullNode, instead of directly serializing null? Answer “null” here is a string, not
Tag: objectmapper
Issues in serializing API request argument in Spring boot application
I have written one aspect to serialize the request arguments for APIs in Spring boot application, in DB as follows: @Pointcut(“within(com.tm.web.rest.*)”) public void …
Serializing map having value of different types to JSON using Jackson in Java
I would like to serialize a given hashmap into json and deserialize it back to the original map. Here I would like to make this generic so that it behaves seamlessly regardless of the type of the …
No serializer found when serializing one Object
I’m trying to return an Object as JSON. Using the /user/id endpoint, I want to display a User based on his Id. When calling this controllerMethod I get the following Exception: My contollerClass looks like this: I checked if al fields have a public getter and tried various options with @JSONIgnoreProperties, but I can’t find it. Displaying all users as
Jackson error “Illegal character… only regular white space allowed” when parsing JSON
I am trying to retrieve JSON data from a URL but get the following error: Illegal character ((CTRL-CHAR, code 31)): only regular white space (r, n,t) is allowed between tokens My code: final URI …