我以前有这种简单的 JSON 数据，我可以成功解析属性并将它们保存到 SQLite 数据库中。

[
  {
  "project_title" : " ",
  "organization_title" : " ",
  "website": "",
  "address": "",
  "keyword" : "",
  "short_code" : "",
  "project_description" : "",
  "smallImageUrl" : "",
  "bigImageUrl" : "",
  "price" : "",
  "country" : "",
  "donationAmount" : "",
  "categories" : "",
  "campaign_id" : "",
  "currency_isoname": "",
  "paypal_email" : "",
  "elv_available" : ""
  }
]

但现在我有这个有点复杂的 JSON 文件:

[
  {
    "location": {
      "deleted_at": "null",
      "documentary_video_length": "81",
      "id": "15",
      "latitude": "52.4134145988286",
      "longitude": "13.0904620846177",
      "position": "5",
      "updated_at": "2011-08-26T15:30:27+02:00",
      "name": "Glienicker Br\u00fccke",
      "text": "",
      "documentary_video_url": "",
      "documentary_thumbnail_url": "",
      "audio_text_url": "",
      "footages": [
        {
          "id": "31",
          "latitude": "52.4134145988286",
          "longitude": "13.0904620846177",
          "position": "12",
          "name": "Glienicker Br\u00fccke 1933",
          "text": "sdcs",
          "thumbnail_url": "",
          "video_url": "",
          "video_length": "2",
          "time_period": {
            "id": "24",
            "name": "1933"
          }
        },
        {
          "id": "32",
          "latitude": "52.4134145988286",
          "longitude": "13.0904620846177",
          "position": "12",
          "name": "Glienicker Br\u00fccke 1985",
          "text": "fvd",
          "thumbnail_url": "",
          "video_url": "",
          "video_length": 35,
          "time_period": {
            "id": 30,
            "name": "1985"
          }
        },
        {
          "id": "33",
          "latitude": "52.4134145988286",
          "longitude": "13.0904620846177",
          "position": "12",
          "name": "Glienicker Br\u00fccke 1989",
          "text": "fghg",
          "thumbnail_url": "",
          "video_url": "",
          "video_length": "41",
          "time_period": {
            "id": "12",
            "name": "1989"
          }
        }
      ]
    }
  }
]

这些是我用来解析 JSON 并将其属性保存到 SQLite 数据库中的类。

IntentService 类

public class Sync extends IntentService {

    public Sync() {
        super("Sync");
    }
    @Override
    protected void onHandleIntent(Intent intent) {
        Database.OpenHelper dbhelper = new Database.OpenHelper(getBaseContext());
        SQLiteDatabase db = dbhelper.getWritableDatabase();
        DefaultHttpClient httpClient = new DefaultHttpClient();
        db.beginTransaction();
        HttpGet request = new HttpGet(
                "https://....");
        try {
            HttpResponse response = httpClient.execute(request);
            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                InputStream instream = response.getEntity().getContent();
                BufferedReader r = new BufferedReader(new InputStreamReader(
                        instream, "UTF-8"), 8000);
                StringBuilder total = new StringBuilder();
                String line;
                while ((line = r.readLine()) != null) {
                    total.append(line);
                }
                instream.close();
                String bufstring = total.toString();
                JSONArray arr = new JSONArray(bufstring);
                Database.Tables tab = Database.Tables.AllTables
                        .get(Database.Project.NAME);
                tab.DeleteAll(db);
                for (int i = 0; i < arr.length(); i++) {
                    tab.InsertJSON(db, (JSONObject) arr.get(i));
                }
                db.setTransactionSuccessful();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        db.endTransaction();
        db.close();
        getContentResolver().notifyChange(
                Uri.withAppendedPath(Provider.CONTENT_URI,
                        Database.Project.NAME), null);

    }

}

SQLite 数据库类

public class Database {

    final OpenHelper openHelper;
    static final String DATABASE_NAME = "mydb";
    static final int DATABASE_VERSION = 6;

    public Database(Context context) throws Exception {
        openHelper = new OpenHelper(context);
    }

    public void Destroy() {
        openHelper.close();
    }

    public static enum ColumnsTypes {
        integer, varchar, guid, datetime, numeric
    };

    static final String COLLATE = "COLLATE LOCALIZED";
    static final String EMPTY = "";

    public static interface Project {
        public static final String NAME = "Project";
        public static String C_PROJECTTITLE = "project_title";
        public static String C_ORGANIZATIONTITLE = "organization_title";
        public static String C_WEBSITE = "website";
        public static String C_ADDRESS = "address";
        public static String C_KEYWORD = "keyword";
        public static String C_SHORTCODE = "short_code";
        public static String C_PROJECTDESCRIPTION = "project_description";
        public static String C_SMALLIMAGE = "smallImageUrl";
        public static String C_BIGIMAGE = "bigImageUrl";
        public static String C_PRICE = "price";
        public static String C_COUNTRY = "country";
        public static String C_DONATIONAMOUNT = "donationAmount";
        public static String C_CATEGORIES = "categories";
        public static String C_CAMPAIGNID = "campaign_id";
        public static String C_PAYPALEMAIL = "paypal_email";
        public static String C_ELVAVAILABLE = "elv_available";
        public static String C_CURRENCY = "currency_isoname";



        public final static String[] C = new String[] { C_PROJECTTITLE,
                C_ORGANIZATIONTITLE, C_WEBSITE, C_ADDRESS, C_KEYWORD, C_SHORTCODE,
                C_PROJECTDESCRIPTION, C_SMALLIMAGE, C_BIGIMAGE, C_PRICE,
                C_COUNTRY, C_DONATIONAMOUNT, C_CATEGORIES, C_CAMPAIGNID, C_PAYPALEMAIL, C_ELVAVAILABLE, C_CURRENCY };
        public final static ColumnsTypes[] CT = new ColumnsTypes[] {
                ColumnsTypes.varchar, ColumnsTypes.varchar,
                ColumnsTypes.varchar, ColumnsTypes.varchar,
                ColumnsTypes.varchar, ColumnsTypes.varchar,
                ColumnsTypes.varchar, ColumnsTypes.varchar,
                ColumnsTypes.varchar,ColumnsTypes.varchar, ColumnsTypes.varchar,
                ColumnsTypes.varchar,ColumnsTypes.varchar,
                ColumnsTypes.varchar,ColumnsTypes.varchar, ColumnsTypes.varchar, ColumnsTypes.varchar};
        public final static boolean[] CN = new boolean[] { false, false, false,
                false, false, false, false, false, false, false, false, false, false, false, false, false,false };
        public final static String[] CS = new String[] { COLLATE, COLLATE,
                COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE, COLLATE };
    }

    public static class Tables {
        String[] columns = null;
        ColumnsTypes[] columnsTypes = null;
        String[] columnsSpecials = null;
        String name = null;
        boolean[] columnsNullable = null;

        Tables(String name, String[] columns, ColumnsTypes[] columnsTypes,
                String[] columnsSpecials, boolean[] columnsNullable) {
            this.name = name;
            this.columns = columns;
            this.columnsTypes = columnsTypes;
            this.columnsSpecials = columnsSpecials;
            this.columnsNullable = columnsNullable;
        }

        public String DropStatment() {
            return "DROP TABLE IF EXISTS " + name;
        }

        public void DeleteAll(SQLiteDatabase db) {
            db.delete(name, null,null);
        }

        public long InsertJSON(SQLiteDatabase db, JSONObject obj)
                throws JSONException {
            ContentValues vals = new ContentValues();
            for (String col : columns) {
                vals.put(col, obj.getString(col));
            }
            return db.insert(name, null, vals);
        }

        public String CreateStatment() {
            StringBuilder sb = new StringBuilder("CREATE TABLE ");
            sb.append(name);
            sb.append(" ([");
            for (int i = 0; i < columns.length; i++) {
                sb.append(columns[i]);
                sb.append("] ");
                sb.append(columnsTypes[i].name());
                sb.append(' ');
                sb.append(columnsSpecials[i]);
                if (!columnsNullable[i])
                    sb.append(" NOT NULL ");
                sb.append(", [");
            }
            sb.append("_id] INTEGER PRIMARY KEY AUTOINCREMENT);");
            return sb.toString();
        }

        public final static Map<String, Tables> AllTables;
        static {
            HashMap<String, Tables> aMap = new HashMap<String, Tables>();
            aMap.put(Project.NAME, new Tables(Project.NAME, Project.C,
                    Project.CT, Project.CS, Project.CN));
            AllTables = Collections.unmodifiableMap(aMap);
        }
    }

    public static class OpenHelper extends SQLiteOpenHelper {

        public OpenHelper(Context context) {
            super(context, DATABASE_NAME, null, DATABASE_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            try {
                for (Tables table : Tables.AllTables.values()) {
                    String create = table.CreateStatment();
                    db.execSQL(create);
                }
            } catch (Exception e) {
                Log.e("Exception", e.toString());
            }
        }

        public OpenHelper Recreate() {
            onUpgrade(getWritableDatabase(), 1, 2);
            return this;
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            for (Tables table : Tables.AllTables.values()) {
                db.execSQL(table.DropStatment());
            }
            onCreate(db);
        }

    }       

ContentProvider 类

public class Provider extends ContentProvider {

    @Override
    public int delete(Uri arg0, String arg1, String[] arg2) {
        return 0;
    }

    private static final int PROJECTS = 1;
    private static final int PROJECT = 2;
    public static final String PROJECTS_MIME_TYPE = ContentResolver.CURSOR_DIR_BASE_TYPE
            + "/Project";
    public static final String PROJECT_MIME_TYPE = ContentResolver.CURSOR_ITEM_BASE_TYPE
            + "/Project";
    public static final String AUTHORITY = "spendino.de";
    public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY);
    static final UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);
    static final HashMap<String, String> map = new HashMap<String, String>();
    static {
        matcher.addURI(AUTHORITY, "Project", PROJECTS);
        matcher.addURI(AUTHORITY, "Project/#", PROJECT);
        map.put(BaseColumns._ID, BaseColumns._ID);
        map.put(Database.Project.C_BIGIMAGE, Database.Project.C_BIGIMAGE);
        map.put(Database.Project.C_COUNTRY, Database.Project.C_COUNTRY);
        map.put(Database.Project.C_KEYWORD, Database.Project.C_KEYWORD);
        map.put(Database.Project.C_ORGANIZATIONTITLE,
                Database.Project.C_ORGANIZATIONTITLE);
        map.put(Database.Project.C_PRICE, Database.Project.C_PRICE);
        map.put(Database.Project.C_PROJECTDESCRIPTION,
                Database.Project.C_PROJECTDESCRIPTION);
        map.put(Database.Project.C_PROJECTTITLE,
                Database.Project.C_PROJECTTITLE);
        map.put(Database.Project.C_SHORTCODE, Database.Project.C_SHORTCODE);
        map.put(Database.Project.C_SMALLIMAGE, Database.Project.C_SMALLIMAGE);
        map.put(Database.Project.C_DONATIONAMOUNT, Database.Project.C_DONATIONAMOUNT);
        map.put(Database.Project.C_WEBSITE, Database.Project.C_WEBSITE);
        map.put(Database.Project.C_ADDRESS, Database.Project.C_ADDRESS);
        map.put(Database.Project.C_CATEGORIES, Database.Project.C_CATEGORIES);
        map.put(Database.Project.C_CAMPAIGNID, Database.Project.C_CAMPAIGNID);
        map.put(Database.Project.C_PAYPALEMAIL, Database.Project.C_PAYPALEMAIL);
        map.put(Database.Project.C_ELVAVAILABLE, Database.Project.C_ELVAVAILABLE);
        map.put(Database.Project.C_CURRENCY, Database.Project.C_CURRENCY);
    }

    @Override
    public String getType(Uri uri) {
        switch (matcher.match(uri)) {
        case PROJECTS:
            return PROJECTS_MIME_TYPE;
        case PROJECT:
            return PROJECT_MIME_TYPE;
        default:
            throw new IllegalArgumentException("Unknown URL " + uri);
        }
    }

    @Override
    public Uri insert(Uri arg0, ContentValues arg1) {
        // TODO Auto-generated method stub
        return null;
    }

    private Database.OpenHelper mDB;

    @Override
    public boolean onCreate() {
        try {
            mDB = new Database.OpenHelper(getContext());
        } catch (Exception e) {
            Log.e("Exception", e.getLocalizedMessage());
            return false;
        }
        return true;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
            String[] selectionArgs, String sortOrder) {
        SQLiteQueryBuilder builder = new SQLiteQueryBuilder();
        switch (matcher.match(uri)) {
        case PROJECTS:
            String table = uri.getPathSegments().get(0);
            builder.setTables(table);
            break;
        case PROJECT:
            table = uri.getPathSegments().get(0);
            builder.setTables(table);
            selection = "_id=?";
            selectionArgs = new String[] { uri.getPathSegments().get(1) };
            break;
        default:
            throw new IllegalArgumentException("Unknown URL " + uri);
        }
        builder.setProjectionMap(map);

        Cursor cursor = builder.query(mDB.getReadableDatabase(), projection, selection,
                selectionArgs, null, null, sortOrder);

        if (cursor == null) {
            return null;
        }
        cursor.setNotificationUri(getContext().getContentResolver(), uri);
        return cursor;
    }

     public int update(Uri uri, ContentValues cv, String selection, String[] selectionArgs) {
         String table = null;
         SQLiteQueryBuilder builder = new SQLiteQueryBuilder();
        switch (matcher.match(uri)) {
         case PROJECTS:
                 table = uri.getPathSegments().get(0);
                 builder.setTables(table);
                 break;
         case PROJECT:
                 table = uri.getPathSegments().get(0);
                 builder.setTables(table);
                 selection = "_id=?";
                 selectionArgs = new String[] { uri.getPathSegments().get(1) };
                 break;
         default:
                 throw new IllegalArgumentException("Unknown URL " + uri);
         }
         return mDB.getWritableDatabase().update(table, cv, selection, selectionArgs);
 }


}

为了使新的 JSON 文件被解析并保存到 SQLite 数据库中，我需要对上述类进行哪些更改？ 我在这里发言是因为我的旧 JSON 文件中没有数组，但我想重新使用我已有的类。我知道我需要更改列名并根据 SQLite 数据库和提供程序类上的 JSON 属性自定义字符串

谢谢

最佳答案

您可以使用 Gson或 Jackson .这些库允许您轻松地构建类“bean”来解析/生成 JSON 输入/输出。

例如在 Gson 中，如果你有一个以这种方式构建的名为 Car 的类:

class Car{
  int wheels;
  String plate;
}

...如果您想解析一系列汽车，您可以通过这种方式轻松地扩充您的 JSON:

Gson gson = new Gson();
List<Car> cars = gson.fromJson(input, new TypeToken<List<Car>>(){}.getType());

非常酷的是，它能够理解您已经包含数组并毫不费力地对其进行解析(我指的是您的输入)。

干杯， 西蒙妮

关于java - 解析 JSON 并将它们保存在 SQLite 数据库中，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/10026855/