using inner class object in outer class java

using inner class object in outer class java

I am facing a problem converting json object to POJO class.
I have a public class called Service and it has an inner class User. I
want to use the inner class as a container/object to hold the variables
for all my outer class methods. I am trying to do the below, but I am
getting compilation errors. Please show how I can do this and please
correct the mistake I am doing in my code below.
Trial 1:
public class Service {
// Method
public boolean createUserAccount(JsonNode node) throws Exception {
ObjectMapper mapper = new ObjectMapper();
User user=null;
try {
Service service=new Service();
user = mapper.readValue(node, User.class);
} catch (Exception e) {throw new Exception("failed to bind json",
e);}
System.out.println("Use this anywhere in method"+userNode.firstName);
}
}
// Inner class
public static class User {
public String firstName;
public String lastName;
}
}
OUTPUT:
NULL POINTER EXCEPTION AND user=null even after execution of
mapper.readValue() statement