JSON Initial capital key issue with parsing in GSON

Question

I have previously JSON response in REST API like below,

Example,

{"id":"1234"}.

I created an POJO class to set it like below.

import com.google.gson.annotations.Expose;
import com.google.gson.annotations.SerializedName;

public class Example {

    @SerializedName("id")
    @Expose
    private String id;

    /**
     *
     * @return
     * The id
     */
    public String getId() {
        return id;
    }

    /**
     *
     * @param id
     * The id
     */
    public void setId(String id) {
        this.id = id;
    }
}

And I am parsing with GSON like below

Example response = new Gson().fromJson(jsonResponse, Example .class);

Now, response is changed to

{"Id":"1234"}

And my whole parsing is returning me null due to initial capital letter.

I tried many things to solve it out but I can't get any solution for it. I have only suggestions like

you should change name of @SerializedName with initial capital (but I have thousands of objects)

Is there any solution that GSON won't depend upon capitalization or lower case of key?

try putting capital ID in @SerializedName("Id") instead of @SerializedName("id") — Nitesh, Oct 05 '15 at 07:06
You can just globally replace all `@SerializedName("id")` with `@SerializedName("Id")`. — mixel, Oct 05 '15 at 07:07
@Nitesh thanks for your suggestion but I need alternative to do such change. because I have thousands of object with SerializedName .. — Chintan Rathod, Oct 05 '15 at 07:07
@mixel don't you think, that answer which you marked duplicate is of 2011. and this question is asked on 2015 year. 4 years of gap make simply a good library changes. — Chintan Rathod, Oct 05 '15 at 07:10
can you check this http://stackoverflow.com/questions/22096274/serialization-object-to-json-using-gson-how-to-set-field-names-in-camelcase — Satyen Udeshi, Oct 05 '15 at 07:18
@ChintanRathod Not much changed since 2011 https://sites.google.com/site/gson/gson-roadmap — mixel, Oct 05 '15 at 07:19

Niko Adrianus Yuwono · Answer 1 · 2015-10-05T07:25:12.707

3

I think you can use FieldNamingPolicy in your Gson Builder like this :

Gson gson = new GsonBuilder()
                .setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES)
                .create();

I think in your case you will need to use LOWER_CASE_WITH_UNDERSCORES or LOWER_CASE_WITH_DASHES based which separator you want to use.

From the docs if you set this flag it will convert camel cased form to a lower case field name.

EDIT:
The SerializedName annotation will override any field naming policy so you need to be careful with it -> source

edited Oct 05 '15 at 07:25

answered Oct 05 '15 at 07:21

Niko Adrianus Yuwono

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I think that `UPPER_CAMEL_CASE` is better suited for his needs. – mixel Oct 05 '15 at 07:24
Nope.. After implementing your solution, it can't solve my problem with UPPER_CAMEL_CASE. – Chintan Rathod Oct 05 '15 at 08:05
That's why I recommended you to use LOWER_CASE_WITH_UNDERSCORES or LOWER_CASE_WITH_DASHES because you want to change "Id" to "id" right? – Niko Adrianus Yuwono Oct 05 '15 at 08:08

JSON Initial capital key issue with parsing in GSON

1 Answers1