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POSimple Json to Java convertion using GSON
 

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  1. POSimple Json to Java convertion using GSON
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    <p>I've recently started using GSON library for deserializing JSON that comes from web service but I can't make it work. I decide to test GSON on some simple input - can't make it any simpler and it still doesn't work. I've looked through similar issues like <a href="https://stackoverflow.com/questions/1688099/converting-json-to-java/">Converting JSON to Java</a>, all of which suggest similar approach to solution. My guess is that I'm missing something really simple and obvious so a fresh view on the code would probably help. So here is what I have:</p> <p>JSON</p> <pre><code>{"A":{"name":"qwrety","value1":1,"value2":2}} </code></pre> <p>Java class</p> <pre><code>import com.google.gson.Gson; public class Main { public static void main(String[] args) { String json = /*getting JSON from server*/ Gson gson = new Gson(); A obj = gson.fromJson(json, A.class); System.out.println(obj); } } class A { private String name; private int value1; private int value2; public String getName() { return name; } public int getValue1() { return value1; } public int getValue2() { return value2; } public void setName(String name) { this.name = name; } public void setValue1(int value1) { this.value1 = value1; } public void setValue2(int value2) { this.value2 = value2; } public String toString() { return String.format("name: %s, value1: %d, value2: %d", name, value1, value2); } } </code></pre> <p>What I get in return is </p> <pre><code>name: null, value1: 0, value2: 0 </code></pre> <p>Anyone can tell what is wrong with this code?</p> <p><strong>UPD</strong> As @torbinsky and @Kevin-Dolan pointed out, the problem was because Java class structure didn't match the Json format. To fix this I added a new class </p> <pre><code>class Container { private A a; public A getA() { return a; } public void setA(A a) { this.a = a; } } </code></pre> <p>and changed the deserialisation call to following</p> <pre><code>Gson gson = new Gson(); Container obj = gson.fromJson(json, Container.class); System.out.println(obj.getA()); </code></pre> <p>However I anyway get "null" printed out</p>
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