解析JSON和創建對象

在我的應用我已經解析這個JSON：解析JSON和創建對象

programs.json

{ 
    "programs": { 
    "program": [ 
     { 
     "programNumber": "1", 
     "imgURL": "http://www.photovideolife.com/userfiles/Placeholder%2001.jpg", 
     "description": "Lorem ipsum dolor sit er elit", 
     "episode": [ 
      { 
      "pN": "1", 
      "episodeNumber": "1", 
      "transmissionName": "Titolo", 
      "date": "29 Giu 2013", 
      "time": "14:30", 
      "channel": "Real Time", 
      "channelLogo": "https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png" 
      }, 
      { 
      "pN": "1", 
      "episodeNumber": "1", 
      "transmissionName": "Titolo", 
      "date": "29 Giu 2013", 
      "time": "16:30", 
      "channel": "DMAX", 
      "channelLogo": "http://tv.zam.it/canali/dmax.png" 
      }, 
      { 
      "pN": "1", 
      "episodeNumber": "2", 
      "transmissionName": "Titolo", 
      "date": "01 Lug 2013", 
      "time": "14:30", 
      "channel": "Real Time", 
      "channelLogo": "https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png" 
      }, 
      { 
      "pN": "1", 
      "episodeNumber": "2", 
      "transmissionName": "Titolo", 
      "date": "01 Lug 2013", 
      "time": "16:30", 
      "channel": "DMAX", 
      "channelLogo": "http://tv.zam.it/canali/dmax.png" 
      } 
     ] 
     }, 
     { 
     "programNumber": "2", 
     "imgURL": "http://mesa.umich.edu/files/mesa/field/image/placeholder2.png", 
     "description": "Lorem ipsum dolor sit er elit", 
     "Episode": [ 
      { 
      "pN": "2", 
      "episodeNumber": "1", 
      "transmissionName": "Titolo 1", 
      "date": "30 Giu 2013", 
      "time": "13:30", 
      "channel": "Real Time", 
      "channelLogo": "https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png" 
      }, 
      { 
      "pN": "2", 
      "episodeNumber": "1", 
      "transmissionName": "Titolo 1", 
      "date": "30 Giu 2013", 
      "time": "18:30", 
      "channel": "DMAX", 
      "channelLogo": "http://tv.zam.it/canali/dmax.png" 
      }, 
      { 
      "pN": "2", 
      "episodeNumber": "2", 
      "transmissionName": "Titolo 1", 
      "date": "01 Lug 2013", 
      "time": "13:30", 
      "channel": "Real Time", 
      "channelLogo": "https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png" 
      }, 
      { 
      "pN": "2", 
      "episodeNumber": "2", 
      "transmissionName": "Titolo 1", 
      "date": "01 Lug 2013", 
      "time": "18:30", 
      "channel": "DMAX", 
      "channelLogo": "http://tv.zam.it/canali/dmax.png" 
      } 
     ] 
     }, 
     { 
     "programNumber": "3", 
     "imgURL": "http://wp.contempographicdesign.com/wp_paramount/wp-content/themes/paramount/images/image_placeholder_lrg.jpg", 
     "description": "Lorem ipsum dolor sit er elit", 
     "Episode": [ 
      { 
      "pN": "3", 
      "episodeNumber": "1", 
      "transmissionName": "Titolo 2", 
      "date": "30 Giu 2013", 
      "time": "10:30", 
      "channel": "Real Time", 
      "channelLogo": "https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png" 
      }, 
      { 
      "pN": "3", 
      "episodeNumber": "1", 
      "transmissionName": "Titolo 2", 
      "date": "30 Giu 2013", 
      "time": "17:30", 
      "channel": "DMAX", 
      "channelLogo": "http://tv.zam.it/canali/dmax.png" 
      }, 
      { 
      "pN": "3", 
      "episodeNumber": "2", 
      "transmissionName": "Titolo 2", 
      "date": "01 Lug 2013", 
      "time": "10:30", 
      "channel": "Real Time", 
      "channelLogo": "https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png" 
      }, 
      { 
      "pN": "3", 
      "episodeNumber": "2", 
      "transmissionName": "Titolo 2", 
      "date": "01 Lug 2013", 
      "time": "17:30", 
      "channel": "DMAX", 
      "channelLogo": "http://tv.zam.it/canali/dmax.png" 
      } 
     ] 
     } 
    ] 
    } 
}

我想創造一些對象，從這個JSON文件存儲數據，所以我使用Gson庫來使這個解析非常簡單。我無法使用此庫中創建對象，我創建了4個對象：

EpisodeData我在其中存儲該信息（PN，episodeNumber，日期，時間，渠道和channelLogo）
情節這是一個EpisodeData
計劃的陣列它的情節數組
程序中，我存儲陣列計劃

這裏是對象的代碼：

EpisodeData.java

public class EpisodeData implements Serializable { 

    /** 
    * 
    */ 
    private static final long serialVersionUID = 1L; 
    public String pN, episodeNumber, transmissionName, date, time, channel, channelLogo; 
}

Episode.java

public class Episode implements Serializable { 

    /** 
    * 
    */ 
    private static final long serialVersionUID = 1L; 
    public EpisodeData[] episodeData; 
}

Program.java

public class Program implements Serializable { 

    /** 
    * 
    */ 
    private static final long serialVersionUID = 1L; 
    public Episode[] episode; 
}

Programs.java

public class Programs implements Serializable { 

    /** 
    * 
    */ 
    private static final long serialVersionUID = 1L; 
    public Program program; 

}

所以，我提出（與AsyncHttpClient）連接到從服務器上下載的JSON文件，我開始分析它，但我有麻煩了。我張貼在這裏的代碼片段：

public void onSuccess(String json) { 
    super.onSuccess(json); 
    Gson decoder = new Gson(); 
    Programs programs = decoder.fromJson(json, Programs.class); 
    Log.d("PROGRAMS", "" + programs.program); 
}

爲什麼我不能訪問到情節和EpisodeData？爲什麼當我嘗試登錄programs.program時，它返回null？

我希望你能幫助我找到這個問題的解決方案謝謝

來源

2013-08-06 lucgian84

您沒有爲獲取數據創建問題類。檢查[此演示]（https://github.com/lalit3686/GSONDemo） –

你說它的代碼不起作用...我試圖在我的星系S2，它顯示我一個白色的活動 – lucgian84

情節應該儘可能多屬性就像你想要解析的一樣，按照它們進入json的方式命名。當他們以「 - 」開頭時，既不能重命名類，也不能解析它們，因爲它們的名稱與Gson期望的不同。嘗試在調用decoder.fromJson之前嘗試使用pN替換-pN，使用episodeNumber替換-episodeNumber等，然後再調用decoder.fromJson，如下所示：json.replaceAll（「 - pN」，「pN」）;等等 –

問題出在基礎對象上。它不應該是程序，而應該是具有「程序」屬性的另一個對象。除此之外，Programs對象還有一個Program作爲屬性的數組，而不是一個實例。

基礎對象：

public class JsonRootObject { 

    public Programs programs; 

}

程序對象：

public class Programs implements Serializable { 

    private static final long serialVersionUID = 1L; 
    public Program []program; 

}

程序對象：

public class Program implements Serializable { 

    private static final long serialVersionUID = 1L; 
    public Episode[] episode; 
}

情節對象：

public class Episode implements Serializable { 

    private static final long serialVersionUID = 1L; 
    public String pN, episodeNumber, transmissionName, date, time, channel, channelLogo; 
    @Override 
    public String toString() { 
     return "Episode [pN=" + pN + ", episodeNumber=" + episodeNumber 
       + ", transmissionName=" + transmissionName + ", date=" 
       + date + ", time=" + time + ", channel=" + channel 
       + ", channelLogo=" + channelLogo + "]"; 
    } 
}

EpisodeData不是必需的，因爲Episode是最後一級。

最後，你可以用它解析：

Gson decoder = new Gson(); 
JsonRootObject programs = decoder.fromJson(json, JsonRootObject.class);

我添加了一個toString方法，以集類來測試解析器，這是結果：

System.out.println(programs.programs.program[0].episode[0]); 

08-06 05:31:58.236: I/System.out(1249): Episode [pN=1, episodeNumber=1, transmissionName=Titolo, date=29 Giu 2013, time=14:30, channel=Real Time, channelLogo=https://lh6.googleusercontent.com/-XSh-9ngYJu4/ThiY-xl2EeI/AAAAAAAABmc/iz04VpL5hOs/s800/realtime.png]

希望幫助:)

來源

2013-08-06 09:33:40

它的工作原理！非常感謝你！ – lucgian84

我想你應該添加@@ SerializedName（「 - PN」）上述領域的PN聲明，這樣做是爲了其他領域太。

來源

2013-08-06 08:22:27 JaredLuo

我已經在我的問題中更新了我的JSON，看一看 – lucgian84

解析JSON和創建對象

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