無法轉換使用GSON的JSON對象POJO（在Android）

Question

我在控制器下面的方法：

public class FoundController { 

private JSONObject accessPoint; 
private JSONArray accessPoints; 
private List<WlanNetwork> accessPointlist; 
private Gson gson; 

public FoundController() { 
    this.accessPoint = new JSONObject(); 
    this.accessPoints = new JSONArray(); 
    this.accessPointlist = new ArrayList<>(); 
    this.gson = new Gson(); 
} 


public List<WlanNetwork> getFoundWlanNetworks() { 
    accessPoints = CommonHelper.getWifiList(Constants.Global.FILE_WPA_SUPLICANT_CONF); 
    accessPointlist = new ArrayList<WlanNetwork>(); 

    for (int i = 0; i < accessPoints.length(); i++) { 
     try { 
      Logger.d(accessPoints.getJSONObject(i).toString()); 
      WlanNetwork accessPointPOJO = gson.fromJson(accessPoints.getJSONObject(i).toString(), WlanNetwork.class); 
      Logger.d(accessPointPOJO.getSssid()); 
      accessPointlist.add(accessPointPOJO); 
     } catch (Exception e) { 
      Logger.e("Exception"); 
      Logger.e(e.getMessage()); 
     } 
    } 
    Logger.d(String.valueOf(accessPointlist.size())); 
    return accessPointlist; 
} 

}

方法：

accessPoints.getJSONObject(i).toString() 

返回：

{"key_mgmt":"NONE","priority\"":"97","ssid":"test"} 

但是，如果我想轉換使用ERT到POJO對象：

WlanNetwork accessPointPOJO = gson.fromJson(accessPoints.getJSONObject(i).toString(), WlanNetwork.class); 

我總是得到以下異常：

No message/exception is set 

Model類如下：

public class WlanNetwork { 
    private String sssid; 
    private String key_mgmt; 
    private String sim_slot; 
    private String imsi; 
    private String priority; 

    public WlanNetwork(String sssid, String key_mgmt, String sim_slot, String imsi, String priority) { 
     super(); 
     this.sssid = sssid; 
     this.key_mgmt = key_mgmt; 
     this.sim_slot = sim_slot; 
     this.imsi = imsi; 
     this.priority = priority; 
    } 

    public String getSssid() { 
     return sssid; 
    } 

    public void setSssid(String sssid) { 
     this.sssid = sssid; 
    } 

    public String getKey_mgmt() { 
     return key_mgmt; 
    } 

    public void setKey_mgmt(String key_mgmt) { 
     this.key_mgmt = key_mgmt; 
    } 

    public String getSim_slot() { 
     return sim_slot; 
    } 

    public void setSim_slot(String sim_slot) { 
     this.sim_slot = sim_slot; 
    } 

    public String getImsi() { 
     return imsi; 
    } 

    public void setImsi(String imsi) { 
     this.imsi = imsi; 
    } 

    public String getPriority() { 
     return priority; 
    } 

    public void setPriority(String priority) { 
     this.priority = priority; 
    } 
} 

我幾乎嘗試了一切，但沒有運氣。有什麼可以錯誤的嗎？

非常感謝您的任何建議。

編輯：

的printStackTrace返回

java.lang.NullPointerException 
10-16 12:54:56.421 11985-11985/com.testr W/System.err﹕ at com.orhanobut.logger.LoggerPrinter.log(LoggerPrinter.java:218) 
10-16 12:54:56.421 11985-11985/com.testr W/System.err﹕ at com.orhanobut.logger.LoggerPrinter.d(LoggerPrinter.java:109) 
10-16 12:54:56.421 11985-11985/com.testr W/System.err﹕ at com.orhanobut.logger.Logger.d(Logger.java:49) 
10-16 12:54:56.421 11985-11985/com.testr W/System.err﹕ at com.testr.controller.FoundController.getFoundWlanNetworks(FoundController.java:38) 
10-16 12:54:56.421 11985-11985/com.testr W/System.err﹕ at com.testr.view.fragment.Fragment_found.processWhatIsNeed(Fragment_found.java:51) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at com.testr.view.fragment.Fragment_found.onActivityCreated(Fragment_found.java:76) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.support.v4.app.Fragment.performActivityCreated(Fragment.java:1970) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1051) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1207) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:738) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1572) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:493) 
10-16 12:54:56.422 11985-11985/com.testr W/System.err﹕ at android.os.Handler.handleCallback(Handler.java:808) 
10-16 12:54:56.423 11985-11985/com.testr W/System.err﹕ at android.os.Handler.dispatchMessage(Handler.java:103) 
10-16 12:54:56.423 11985-11985/com.testr W/System.err﹕ at android.os.Looper.loop(Looper.java:193) 
10-16 12:54:56.423 11985-11985/com.testr W/System.err﹕ at android.app.ActivityThread.main(ActivityThread.java:5395) 
10-16 12:54:56.423 11985-11985/com.testr W/System.err﹕ at java.lang.reflect.Method.invokeNative(Native Method) 
10-16 12:54:56.423 11985-11985/com.testr W/System.err﹕ at java.lang.reflect.Method.invoke(Method.java:515) 
10-16 12:54:56.423 11985-11985/com.testr W/System.err﹕ at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:837) 
10-16 12:54:56.424 11985-11985/com.testr W/System.err﹕ at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:653) 
10-16 12:54:56.424 11985-11985/com.testr W/System.err﹕ at dalvik.system.NativeStart.main(Native Method) 

Answer 1

檢查JSON字符串。 「優先級」鍵附近有一個額外的報價和反斜槓。

{"key_mgmt":"NONE","priority\"":"97","ssid":"test"} 

而且服務響應鍵「ssid」與POJO類屬性「sssid」不匹配。更改POJO類的屬性名稱。