我的 JSON 输出有什么问题？ retrofit.converter.ConversionException

Question

我正在尝试对一些 json 进行 retro fit，但看不出我的 json 字符串有什么问题，我不断收到同样的错误。

我期待一个单词对象列表，但我错过了什么？有什么想法吗？

retrofit.converter.ConversionException: com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $

JSON:

{
    "words": [
        {
            "id": "1",
            "word": "submarine",
            "word_syllables": "sub-mar-ine",
            "picture": "none.jpg",
            "picture_dir": "",
            "soundfile": "",
            "user_id": "1",
            "created": "2015-04-08 16:32:07",
            "modified": "0000-00-00 00:00:00"
        },
        {
            "id": "2",
            "word": "computer",
            "word_syllables": "com-pute-r",
            "picture": "computer.jpg",
            "picture_dir": "",
            "soundfile": "",
            "user_id": "0",
            "created": "2015-04-08 16:32:07",
            "modified": "0000-00-00 00:00:00"
        }
    ]
}

改造Android代码：

private void requestData(){

    RestAdapter adapter=new RestAdapter.Builder()
    .setEndpoint(ENDPOINT)
    .build();

    WordsAPI api=adapter.create(WordsAPI.class);

    api.getRestWordFeed(new Callback<List<Word>>(){

            @Override
            public void failure(RetrofitError arg0) {
                // TODO Auto-generated method stub
                Log.v("error",arg0.getMessage());
            }

            @Override
            public void success(List arg0, Response arg1) {
                // TODO Auto-generated method stub  
                wordList=arg0;
                printList();                    
            }
    });

}

API接口：

package com.example.testretrofitlib;

import java.util.List;

import retrofit.Callback;
import retrofit.http.GET;

public interface WordsAPI { 

    @GET("/rest_words/index.json")
    public void getRestWordFeed(Callback<List<Word>> response);


}

Answer 1

JSON 的单词对象列表嵌入在具有 "words" 属性的对象的值中。该错误只是指出，它期待一个数组定界符 [ 而不是它找到了该对象的开头。

您可以修复 JSON（删除 {"words": <ACTUAL_ARRAY> } 并只留下两个元素的数组）或修改您在 getRestWordFeed 中期望的数据结构。

Answer 2

您的 JSON 是一个具有一个属性的对象：'words' 这是一个词对象数组。您的错误："Expected BEGIN_ARRAY but was BEGIN_OBJECT" 表示您需要一个数组，但 return 编辑了一个对象。一种解决方案是 return 以下 json:

[
    {
        "id": "1",
        "word": "submarine",
        "word_syllables": "sub-mar-ine",
        "picture": "none.jpg",
        "picture_dir": "",
        "soundfile": "",
        "user_id": "1",
        "created": "2015-04-08 16:32:07",
        "modified": "0000-00-00 00:00:00"
    },
    {
        "id": "2",
        "word": "computer",
        "word_syllables": "com-pute-r",
        "picture": "computer.jpg",
        "picture_dir": "",
        "soundfile": "",
        "user_id": "0",
        "created": "2015-04-08 16:32:07",
        "modified": "0000-00-00 00:00:00"
    }
]

我的 JSON 输出有什么问题？ retrofit.converter.ConversionException

What's wrong with my JSON Output? retrofit.converter.ConversionException

java

android

json

gson

retrofit