如何在android中使用GSON解析json解析

Posted 2023-04-19

【中文标题】如何在android中使用GSON解析json解析

【英文标题】：How to parse json parsing Using GSON in android

【发布时间】：2014-05-10 07:52:55

【问题描述】：

我正在使用GSON 来解析 Json 数据。我的 Json 数据如下：

    "count": "12",
    "colbreak": 1,
    "name": "unary rels",
    "score": "9090",
    "Words": [
        
            "count": 6,
            "word": "prp_għaċ-",
            "name": "prp_għaċ-",
            "score": 9.1,
            "Words": "kol",
            "seek": 2231297
        
    ],
    "seek": 0

GsonParse.java

public class GsonParse 


 @SerializedName("count")
 public String count;

 @SerializedName("colbreak")
 public String colbreak;

 @SerializedName("name")
 public String count;
 @SerializedName("score")
 public String score;

 @SerializedName("Words")
 public List<Words> mWords = new ArrayList<Words>();

 @SerializedName("seek")
 public String seek;

我正在使用下面的方法来解析这个 JSON 数据。

public static <T> ArrayList<T> JsonParse(T t, String response) 
        // convert String into InputStream
        InputStream in = new ByteArrayInputStream(response.getBytes());
        JsonReader reader;
        ArrayList<T> lcs = new ArrayList<T>();
        try 
            reader = new JsonReader(new InputStreamReader(in, "UTF-8"));
            Gson gson = new Gson();

            reader.beginObject();
            while (reader.hasNext()) 

                T cse = (T) gson.fromJson(reader, t.getClass());
                lcs.add(cse);
            

            reader.endObject();

            /*
             * reader.nextName(); reader.nextString(); reader.nextName();
             * reader.nextString();
             */
            reader.close();
         catch (UnsupportedEncodingException e) 
            // TODO Auto-generated catch block
            e.printStackTrace();
         catch (IOException e) 
            // TODO Auto-generated catch block
            e.printStackTrace();
        

        return (ArrayList<T>) lcs;
    

我面临以下错误。

03-31 10:14:26.968: E/androidRuntime(18578): com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was NAME at line 1 column 73

【问题讨论】：

请发布错误日志。

请同时发布Words class。

@Sid 如何解析这个 json 字符串？

【参考方案1】：

您可以尝试像这样读取 gson 值：

try 
      AssetManager assetManager = getAssets();
  InputStream ims = assetManager.open("file.txt");

  Gson gson = new Gson();
  Reader reader = new InputStreamReader(ims);

  GsonParse gsonObj = gson.fromJson(reader, GsonParse.class);

     catch(IOException e) 
       e.printStackTrace();
 

假设您只是收到这一块而不是列表。而且这些数据当前位于 assets 文件夹中的一个文件中。您可以将其更改为要从中读取的流。

你使用的类应该是这样的：

GsonParse.class

public class GsonParse 
 @SerializedName("count")
 private String count;

 @SerializedName("colbreak")
 private String colbreak;

 @SerializedName("name")
 private String name;

 @SerializedName("score")
 private String score;

 @SerializedName("Words")
 private List<Words> mWords = new ArrayList<Words>();

 @SerializedName("seek")
 private String seek;

public String getCount() 
    return count;


public void setCount(String count) 
    this.count = count;


public String getColbreak() 
    return colbreak;


public void setColbreak(String colbreak) 
    this.colbreak = colbreak;


private String getName() 
    return name;


private void setName(String name) 
    this.name = name;


public String getScore() 
    return score;


public void setScore(String score) 
    this.score = score;


public List<Words> getmWords() 
    return mWords;


public void setmWords(List<Words> mWords) 
    this.mWords = mWords;


public String getSeek() 
    return seek;


public void setSeek(String seek) 
    this.seek = seek;

Words.class

public class Words 
@SerializedName(value ="count")
private String count;
@SerializedName(value="word")
private String word;
@SerializedName(value="score")
private String name;
@SerializedName(value="Words")
private String words;
@SerializedName(value="seek")
private String seek;

    public String getCount() 
    return count;

public void setCount(String count) 
    this.count = count;

public String getWord() 
    return word;

public void setWord(String word) 
    this.word = word;

public String getName() 
    return name;

public void setName(String name) 
    this.name = name;

public String getWords() 
    return words;

public void setWords(String words) 
    this.words = words;

public String getSeek() 
    return seek;

public void setSeek(String seek) 
    this.seek = seek;

words.class中缺少一个参数，你可以添加它。

GSON 不直接支持 UTF-8 字符。所以当使用 http 接收响应时，您必须在 http 本身的响应中将其转换为 utf-8 格式。

您可以尝试使用：

String jsonString = new Gson().toJson(objectToEncode);
byte[] utf8JsonString = jsonString.getBytes("UTF8");
responseToClient.write(utf8JsonString, 0, utf8JsonString.Length);

【讨论】：

Gson 不使用 get/swt 为什么要制作它们？至少如果你想添加 get/set 使字段私有

@MarcoAcierno 是的 gson 不使用它们，只是为了获取数据:).. 正确它们应该是私有的。我简单地选择了用户的类 :).. 我改变了.. :)

【参考方案2】：

你好使用下面的 gradle lib

compile 'com.google.code.gson:gson:2.2.4'

Json 类

import java.util.List;
public class GsonParse

/**
 * count : 12
 * colbreak : 1
 * name : unary rels
 * score : 9090
 * Words : ["count":6,"word":"prp_għaċ-","name":"prp_għaċ-","score":9.1,"Words":"kol","seek":2231297]
 * seek : 0
 */

private String count;
private int colbreak;
private String name;
private String score;
private int seek;
/**
 * count : 6
 * word : prp_għaċ-
 * name : prp_għaċ-
 * score : 9.1
 * Words : kol
 * seek : 2231297
 */

private List<WordsBean> Words;

public String getCount() 
    return count;


public void setCount(String count) 
    this.count = count;


public int getColbreak() 
    return colbreak;


public void setColbreak(int colbreak) 
    this.colbreak = colbreak;


public String getName() 
    return name;


public void setName(String name) 
    this.name = name;


public String getScore() 
    return score;


public void setScore(String score) 
    this.score = score;


public int getSeek() 
    return seek;


public void setSeek(int seek) 
    this.seek = seek;


public List<WordsBean> getWords() 
    return Words;


public void setWords(List<WordsBean> Words) 
    this.Words = Words;


public static class WordsBean 
    private int count;
    private String word;
    private String name;
    private double score;
    private String Words;
    private int seek;

    public int getCount() 
        return count;
    

    public void setCount(int count) 
        this.count = count;
    

    public String getWord() 
        return word;
    

    public void setWord(String word) 
        this.word = word;
    

    public String getName() 
        return name;
    

    public void setName(String name) 
        this.name = name;
    

    public double getScore() 
        return score;
    

    public void setScore(double score) 
        this.score = score;
    

    public String getWords() 
        return Words;
    

    public void setWords(String Words) 
        this.Words = Words;
    

    public int getSeek() 
        return seek;
    

    public void setSeek(int seek) 
        this.seek = seek;
    

调用 API 将响应放入下面的代码并检索数据

GsonParse gsonparse = gson.fromJson(response, GsonParse.class);
//gsonparse.getWords() // It will returns list of Words
//Also do loop and get more data using data
gsonparse.getColbreak();
gsonparse.getSeek();
for (GsonParse.WordsBean data:gsonparse.getWords())


    data.getName();

希望对你有所帮助..

【讨论】：

在获取数据时给出警告

【参考方案3】：

替换

@SerializedName("name")
public String count;

与

@SerializedName("name")
public String name;

我想问题是您同时使用 public String count; 和 @SerializedName("count") 和 @SerializedName("name")

谢谢。

【讨论】：

这让我很吃惊，但是为什么用户没有收到一个编译时错误，说明计数已经定义？

【参考方案4】：

试试这个：

JSONArray jsonarray = jsonObject.getJSONArray("responseData");
Type listType = new TypeToken<ArrayList<AllUsers>>().getType();
List<AllUsers> allUserses = 
    new GsonBuilder().create().fromJson(jsonarray.toString(), listType);

for(AllUsers user: allUserses)
         allUsersDao.insertOrReplace(user);

【讨论】：

尝试格式化你的代码，我猜一些解释不会造成任何伤害。

【参考方案5】：

您的代码中缺少很多东西..

请查看下面的代码并尝试此代码..

import java.util.List;

public class GsonParse 

    public GsonParse() 
    

    public String count = "";
    public String colbreak = "";
    public String name = "";
    public String score = "";
    public int seek = 0;
    List<WordsData> Words;

    public String getCount() 
        return count;
    

    public void setCount(String count) 
        this.count = count;
    

    public String getColbreak() 
        return colbreak;
    

    public void setColbreak(String colbreak) 
        this.colbreak = colbreak;
    

    public String getName() 
        return name;
    

    public void setName(String name) 
        this.name = name;
    

    public String getScore() 
        return score;
    

    public void setScore(String score) 
        this.score = score;
    

    public int getSeek() 
        return seek;
    

    public void setSeek(int seek) 
        this.seek = seek;
    

    public List<WordsData> getWords() 
        return Words;
    

    public void setWords(List<WordsData> words) 
        Words = words;
    

    public class WordsData 

        public WordsData() 
        

        public int count = 0;
        public String word = "";
        public String name = "";
        public double score = 0.0;
        public String Words = "";
        public int seek = 0;

        public int getCount() 
            return count;
        

        public void setCount(int count) 
            this.count = count;
        

        public String getWord() 
            return word;
        

        public void setWord(String word) 
            this.word = word;
        

        public String getName() 
            return name;
        

        public void setName(String name) 
            this.name = name;
        

        public double getScore() 
            return score;
        

        public void setScore(double score) 
            this.score = score;
        

        public String getWords() 
            return Words;
        

        public void setWords(String words) 
            Words = words;
        

        public int getSeek() 
            return seek;
        

        public void setSeek(int seek) 
            this.seek = seek;
        
    

更多详情请看example

【讨论】：

@dipali，如果 JSON 字段名称与您的实例变量名称不同，您只需要使用“@serializedName”。当字段名称与实例变量名称完全匹配时，gson 足够聪明。