java - builder pattern json deserialize -

i have problem. used example of jackson json deserializing builder pattern empty json. use jackson-databind version 2.8.4 missing something? code follows:

the value class

import com.fasterxml.jackson.databind.annotation.jsondeserialize;  @jsondeserialize(builder=valuebuilder.class) public class value {    private final int x, y;    protected value(int x, int y) {        this.x = x;        this.y = y;    } } 

the valuebuilder class

import com.fasterxml.jackson.annotation.jsoncreator;  //@jsonpojobuilder(buildmethodname = "build", withprefix = "with") public class valuebuilder {    private int x;    private int y;     // can use @jsoncreator use non-default ctor, inject values etc    public valuebuilder() { }     // if name "withxxx", works is: otherwise use @jsonproperty("x") or @jsonsetter("x")! public valuebuilder withx(int x) {     this.x = x;     return this; // or, construct new instance, return } public valuebuilder withy(int y) {     this.y = y;     return this; } @jsoncreator public value build() {     return new value(x, y);   } } 

the start class

public class start {    public static void main(string[] args) throws ioexception {        value newvalue = new valuebuilder().withx(2).withy(4).build();        objectmapper mapper = new objectmapper();        string jsonstring =  mapper.writevalueasstring(newvalue);        system.out.println(jsonstring);      } } 

you're missing accessible getters x , y in value class - objectmapper requires access in order serialize.

add following value class definition:

public int getx() {     return x; } public int gety() {     return y;    } 

no need additional annotations in context.

your json print out like:

{"x":2,"y":4} 

you make fields public reach same result, defile proper encapsulation.