如何修复安卓 java中的sqliteException
我试图将值插入到数据库以及内容提供程序中，但得到空sqlite异常。在使用content provider类之前，我的数据会毫无问题地添加到数据库中。尝试内容提供商后，我遇到异常。另外，我不知道是否为内容提供商插入了值。。。。。 在SpecificActivity类中，我需要使用LoadImageAsyncTask类返回的drawable，但我在那里得到了null值。。。 帮我解决这些问题
public class FeedReaderContract {
public static class FeedEntry implements BaseColumns {
public static final String TABLE_NAME = "entry";
public static final String _ID = BaseColumns._ID;
public static final String COLUMN_NAME_TITLE = "title";
public static final String COLUMN_NAME_CONTENT = "content";
public static final String COLUMN_NAME_IMAGE = "image";
public static final String COLUMN_NAME_CHANNEL = "channel";
}
}
public class FeedReaderDbHelper extends SQLiteOpenHelper {
public static final int DATABASE_VERSION = 1;
public static final String DATABASE_NAME = "FeedReader.db";
Context context;
public Context getContext() {
return context;
}
private static final String SQL_CREATE_ENTRIES =
"CREATE TABLE " + FeedReaderContract.FeedEntry.TABLE_NAME + " (" +
FeedReaderContract.FeedEntry._ID + " INTEGER PRIMARY KEY, " +
FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE + " TEXT, " +
FeedReaderContract.FeedEntry.COLUMN_NAME_CONTENT + " TEXT, " +
FeedReaderContract.FeedEntry.COLUMN_NAME_CHANNEL + " TEXT, " +
FeedReaderContract.FeedEntry.COLUMN_NAME_IMAGE + " TEXT); ";
private static final String SQL_DELETE_ENTRIES =
"DROP TABLE IF EXISTS " + FeedReaderContract.FeedEntry.TABLE_NAME;
public FeedReaderDbHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.context = context;
}
public void onCreate(SQLiteDatabase db) {
NewsFeedProvider.db = db;
db.execSQL(SQL_CREATE_ENTRIES);
Log.e("sql db", "created");
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL(SQL_DELETE_ENTRIES);
onCreate(db);
}
public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + FeedReaderContract.FeedEntry.TABLE_NAME);
onCreate(db);
}
public void getData(long id) {
try {
Log.e("entered", "getdata");
SQLiteDatabase db = getReadableDatabase();
Cursor cursor = db.query(FeedReaderContract.FeedEntry.TABLE_NAME, new String[] {
FeedReaderContract.FeedEntry._ID, FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE, FeedReaderContract.FeedEntry.COLUMN_NAME_CHANNEL, FeedReaderContract.FeedEntry.COLUMN_NAME_CONTENT, FeedReaderContract.FeedEntry.COLUMN_NAME_IMAGE
}, FeedReaderContract.FeedEntry._ID + "=?", new String[] {
String.valueOf(id)
}, null, null, null, null);
ArrayList < NewsReport > newsReports = new ArrayList < > ();
List itemIds = new ArrayList < > ();
while (cursor.moveToNext()) {
newsReports.add(new NewsReport(cursor.getString(cursor.getColumnIndex(FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE)),
cursor.getString(cursor.getColumnIndex(FeedReaderContract.FeedEntry.COLUMN_NAME_CHANNEL)),
cursor.getString(cursor.getColumnIndex(FeedReaderContract.FeedEntry.COLUMN_NAME_CONTENT)),
cursor.getString(cursor.getColumnIndex(FeedReaderContract.FeedEntry.COLUMN_NAME_IMAGE))));
long itemId = cursor.getLong(
cursor.getColumnIndexOrThrow(FeedReaderContract.FeedEntry._ID));
itemIds.add(itemId);
Log.e("id", "" + itemId);
}
cursor.close();
Log.e("newsreportsize", "dbhelper" + newsReports.size());
if (newsReports.size() != 0) {
for (int i = 0; i < newsReports.size(); i++) {
Log.e("news pic", "" + newsReports.get(i).getPic());
Log.e("news title", "" + newsReports.get(i).getTitle());
Log.e("news content", "" + newsReports.get(i).getContent());
Log.e("news chanel", "" + newsReports.get(i).getNewsChannel());
}
}
} catch (Exception ex) {
Log.e("exception req data", "" + ex);
}
}
}
public class LoadImageAsyncTask extends AsyncTask < String, Void, Drawable > {
private Drawable drawable;
String imageUrl;
private Drawable image;
@Override
protected Drawable doInBackground(String...strings) {
try {
InputStream is = (InputStream) new URL(imageUrl).getContent();
Drawable d = Drawable.createFromStream(is, "src name");
Log.e("drwable", "" + d);
} catch (Exception e) {
Log.e("Specific Activity", "Converting drawable" + e);
}
return drawable;
}
@Override
protected void onPostExecute(Drawable drawableImage) {
super.onPostExecute(drawableImage);
setImage(drawableImage);
}
public void setImage(Drawable drawable) {
new SpecificNewsReportActivity().drawable = drawable;
Log.e("set image", "" + drawable);
this.drawable = drawable;
}
public Drawable getImage() {
Log.e("get image", "" + drawable);
return drawable;
}
}
public class NewsFeedProvider extends ContentProvider {
static final String PROVIDER_NAME = "com.example.newsreport";
static final String URL = "content://" + PROVIDER_NAME + "/newsfeed";
static final Uri CONTENT_URL = Uri.parse(URL);
static final int uriCode = 1;
static String newsTitle;
static String newsContent;
static String newsImage;
static String newsChannel;
static final UriMatcher uriMatcher;
private FeedReaderDbHelper dbHelper;
private static HashMap < String, String > values;
public static SQLiteDatabase db;
static {
uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
uriMatcher.addURI(PROVIDER_NAME, "newsfeed", uriCode);
}
@Override
public boolean onCreate() {
dbHelper = new FeedReaderDbHelper(getContext());
return true;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables(FeedReaderContract.FeedEntry.TABLE_NAME);
switch (uriMatcher.match(uri)) {
case uriCode:
queryBuilder.setProjectionMap(values);
break;
default:
throw new IllegalArgumentException("Unknown URI" + uri);
}
//Cursor cursor=queryBuilder.query(dbHelper.getReadableDatabase(),projection,selection,selectionArgs,null,null,sortOrder);
Cursor cursor = dbHelper.getReadableDatabase().query(FeedReaderContract.FeedEntry.TABLE_NAME, projection, FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE + "= ?", selectionArgs, null, null, sortOrder);
cursor.setNotificationUri(getContext().getContentResolver(), uri);
return cursor;
}
@Override
public String getType(Uri uri) {
switch (uriMatcher.match(uri)) {
case uriCode:
return "vnd.安卓.cursor.dir/newsfeed";
default:
throw new IllegalArgumentException("Unsupported URI" + uri);
}
}
@Override
public Uri insert(Uri uri, ContentValues contentValues) {
SQLiteDatabase db = dbHelper.getWritableDatabase();
long rowId = db.insert(FeedReaderContract.FeedEntry.TABLE_NAME, null, contentValues);
if (rowId > 0) {
Uri _uri = ContentUris.withAppendedId(CONTENT_URL, rowId);
getContext().getContentResolver().notifyChange(_uri, null);
Log.e("insert", "feedreader" + contentValues);
return _uri;
} else {
Toast.makeText(getContext(), "Row insert failed", Toast.LENGTH_SHORT).show();
return null;
}
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
int rowsDeleted = 0;
SQLiteDatabase db = dbHelper.getWritableDatabase();
switch (uriMatcher.match(uri)) {
case uriCode:
rowsDeleted = db.delete(FeedReaderContract.FeedEntry.TABLE_NAME, selection, selectionArgs);
break;
default:
throw new IllegalArgumentException("Unknown URI" + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return rowsDeleted;
}
@Override
public int update(Uri uri, ContentValues contentValues, String selection, String[] selectionArgs) {
int rowsUpdated = 0;
SQLiteDatabase db = dbHelper.getWritableDatabase();
switch (uriMatcher.match(uri)) {
case uriCode:
rowsUpdated = db.delete(FeedReaderContract.FeedEntry.TABLE_NAME, selection, selectionArgs);
break;
default:
throw new IllegalArgumentException("Unknown URI" + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return rowsUpdated;
}
}
public class NewsReportActivity extends AppCompatActivity implements LoaderManager.LoaderCallbacks < ArrayList < NewsReport >> {
ProgressBar progressBar;
FeedReaderDbHelper dbHelper;
SQLiteDatabase db;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.recycler_view);
dbHelper = new FeedReaderDbHelper(this);
db = dbHelper.getWritableDatabase();
Log.e("application", "" + dbHelper);
Intent intent = getIntent();
if (intent.hasExtra("exception")) {
TextView connectionTextView = (TextView) findViewById(R.id.no_connection_text_view);
connectionTextView.setText("There is no internet connection!!!");
} else {
Log.e("no exception", "entered else");
}
getSupportLoaderManager().initLoader(0, null, this);
}
@NonNull
@Override
public Loader < ArrayList < NewsReport >> onCreateLoader(int id, @Nullable Bundle args) {
NewsReportLoader newsReportLoader = new NewsReportLoader(this);
newsReportLoader.forceLoad();
progressBar = (ProgressBar) findViewById(R.id.progress_bar);
progressBar.setVisibility(View.VISIBLE);
return newsReportLoader;
}
@Override
public void onLoadFinished(@NonNull Loader < ArrayList < NewsReport >> loader, ArrayList < NewsReport > data) {
try {
Log.e("data", "" + data.size());
NewsReportAdapter adapter = new NewsReportAdapter(this, data);
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
progressBar.setVisibility(View.INVISIBLE);
recyclerView.setAdapter(adapter);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
DividerItemDecoration mDividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(),
new LinearLayoutManager(this).getOrientation());
recyclerView.addItemDecoration(mDividerItemDecoration);
if (dbHelper != null) {
Log.e("dbhelper", "notnull");
db = dbHelper.getWritableDatabase();
if (db != null) {
Log.e("db", "notnull");
for (int i = 0; i < data.size(); i++) {
ContentValues values = new ContentValues();
NewsReport newsReport = data.get(i);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE, newsReport.getTitle());
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_CONTENT, newsReport.getContent());
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_CHANNEL, newsReport.getNewsChannel());
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_IMAGE, newsReport.getPic());
values.put(NewsFeedProvider.newsTitle, newsReport.getTitle());
values.put(NewsFeedProvider.newsContent, newsReport.getContent());
values.put(NewsFeedProvider.newsChannel, newsReport.getNewsChannel());
values.put(NewsFeedProvider.newsImage, newsReport.getPic());
try {
Uri uri = getApplicationContext().getContentResolver().insert(NewsFeedProvider.CONTENT_URL, values);
} catch (Exception ex) {
Log.e("exception in resolver" + getContentResolver(), "" + ex);
}
long newRowId = db.insert(FeedReaderContract.FeedEntry.TABLE_NAME, null, values);
Log.e("new row id", "" + newRowId);
dbHelper.getData(newRowId);
}
} else
Log.e("db", "null");
} else {
Log.e("dbhelper", "null");
}
// db.execSQL("delete from "+ FeedReaderContract.FeedEntry.TABLE_NAME);
} catch (Exception ex) {
Log.e("newsactivity", "" + FeedReaderContract.FeedEntry.TABLE_NAME.length());
Log.e("onloadfinished", "" + ex);
Log.e("datahelper", "" + dbHelper.getReadableDatabase().rawQuery("SELECT * FROM " + FeedReaderContract.FeedEntry.TABLE_NAME, null));
}
}
@Override
public void onLoaderReset(@NonNull Loader < ArrayList < NewsReport >> loader) {
}
}
public class SpecificNewsReportActivity extends AppCompatActivity {
private TextView contentTextView, titleTextView;
public ImageView imageView;
private Intent intent;
public Drawable drawable;
private String imageUrl;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_specific_news_report);
ActionBar actionBar = this.getSupportActionBar();
if (actionBar != null) {
actionBar.setDisplayHomeAsUpEnabled(true);
}
intent = getIntent();
LoadImageAsyncTask task = new LoadImageAsyncTask();
AsyncTask < String, Void, Drawable > d = task.execute();
try {
drawable = d.get();
} catch (ExecutionException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
imageUrl = getIntent().getStringExtra("image");
Log.e("drawable specific", "" + drawable);
drawable = new LoadImageAsyncTask().getImage();
contentTextView = (TextView) findViewById(R.id.specific_news_report_content_text_view);
titleTextView = (TextView) findViewById(R.id.specific_news_report_title_text_view);
imageView = (ImageView) findViewById(R.id.specific_news_report_image_view);
contentTextView.setText(intent.getStringExtra("content"));
titleTextView.setText(intent.getStringExtra("title"));
try {
if (drawable != null) {
imageView.setImageDrawable(drawable);
} else {
Log.e("returned drawable", "null");
}
} catch (Exception ex) {
Log.e("enna exception", "" + ex);
}
}
@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item) {
int id = item.getItemId();
if (id == 安卓.R.id.home) {
Intent intent = NavUtils.getParentActivityIntent(this);
NavUtils.navigateUpTo(this, intent);
}
return super.onOptionsItemSelected(item);
}
}
堆栈跟踪
2019-07-29 13:57:20.172 24098-24098/com.example.newsreport E/SQLiteLog: (1) near "null": syntax error
2019-07-29 13:57:20.177 24098-24098/com.example.newsreport E/SQLiteDatabase: Error inserting channel=News18.com null=https://images.news18.com/ibnlive/uploads/2019/07/yediyurappa-1.jpg image=https://images.news18.com/ibnlive/uploads/2019/07/yediyurappa-1.jpg title=Karnataka Assembly Trust Vote LIVE: Yediyurappa Wins Floor Test, Speaker Ramesh Kumar Resigns - News18 content=Eleven Congress MLAs and three JDS lawmakers faced the axe from the Speaker in addition to the three disqualified earlier, bringing down the majority mark to 104, one less than the current strength of 105 of the BJP, which also enjoys the support of an Indepe… [+3489 chars]
安卓.database.sqlite.SQLiteException: near "null": syntax error (code 1 SQLITE_ERROR): , while compiling: INSERT INTO entry(channel,null,image,title,content) VALUES (?,?,?,?,?)
at 安卓.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
at 安卓.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:903)
at 安卓.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:514)
at 安卓.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
at 安卓.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
at 安卓.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
at 安卓.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1562)
at 安卓.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1433)
at com.example.newsreport.NewsFeedProvider.insert(NewsFeedProvider.java:78)
at 安卓.content.ContentProvider$Transport.insert(ContentProvider.java:265)
at 安卓.content.ContentResolver.insert(ContentResolver.java:1587)
at com.example.newsreport.NewsReportActivity.onLoadFinished(NewsReportActivity.java:96)
at com.example.newsreport.NewsReportActivity.onLoadFinished(NewsReportActivity.java:29)
at 安卓x.loader.app.LoaderManagerImpl$LoaderObserver.onChanged(LoaderManagerImpl.java:250)
at 安卓x.lifecycle.LiveData.considerNotify(LiveData.java:113)
at 安卓x.lifecycle.LiveData.dispatchingValue(LiveData.java:131)
at 安卓x.lifecycle.LiveData.setValue(LiveData.java:289)
at 安卓x.lifecycle.MutableLiveData.setValue(MutableLiveData.java:33)
at 安卓x.loader.app.LoaderManagerImpl$LoaderInfo.setValue(LoaderManagerImpl.java:189)
at 安卓x.loader.app.LoaderManagerImpl$LoaderInfo.onLoadComplete(LoaderManagerImpl.java:174)
at 安卓x.loader.content.Loader.deliverResult(Loader.java:132)
at 安卓x.loader.content.AsyncTaskLoader.dispatchOnLoadComplete(AsyncTaskLoader.java:258)
at 安卓x.loader.content.AsyncTaskLoader$LoadTask.onPostExecute(AsyncTaskLoader.java:83)
at 安卓x.loader.content.ModernAsyncTask.finish(ModernAsyncTask.java:490)
at 安卓x.loader.content.ModernAsyncTask$InternalHandler.handleMessage(ModernAsyncTask.java:507)
at 安卓.os.Handler.dispatchMessage(Handler.java:106)
at 安卓.os.Looper.loop(Looper.java:193)
at 安卓.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.安卓.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.安卓.internal.os.ZygoteInit.main(ZygoteInit.java:858)
2019-07-29 13:57:20.218 24098-24098/com.example.newsreport E/SQLiteLog: (1) near "null": syntax error
2019-07-29 13:57:20.220 24098-24098/com.example.newsreport E/SQLiteDatabase: Error inserting channel=News18.com null=https://images.news18.com/ibnlive/uploads/2019/07/yediyurappa-1.jpg image=https://images.news18.com/ibnlive/uploads/2019/07/yediyurappa-1.jpg title=Karnataka Assembly Trust Vote LIVE: Yediyurappa Wins Floor Test, Speaker Ramesh Kumar Resigns - News18 content=Eleven Congress MLAs and three JDS lawmakers faced the axe from the Speaker in addition to the three disqualified earlier, bringing down the majority mark to 104, one less than the current strength of 105 of the BJP, which also enjoys the support of an Indepe… [+3489 chars]
安卓.database.sqlite.SQLiteException: near "null": syntax error (code 1 SQLITE_ERROR): , while compiling: INSERT INTO entry(channel,null,image,title,content) VALUES (?,?,?,?,?)
at 安卓.database.sqlite.SQLiteConnection.nativePrepareStatement(Native Method)
at 安卓.database.sqlite.SQLiteConnection.acquirePreparedStatement(SQLiteConnection.java:903)
at 安卓.database.sqlite.SQLiteConnection.prepare(SQLiteConnection.java:514)
at 安卓.database.sqlite.SQLiteSession.prepare(SQLiteSession.java:588)
at 安卓.database.sqlite.SQLiteProgram.<init>(SQLiteProgram.java:58)
at 安卓.database.sqlite.SQLiteStatement.<init>(SQLiteStatement.java:31)
at 安卓.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1562)
at 安卓.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1433)
at com.example.newsreport.NewsReportActivity.onLoadFinished(NewsReportActivity.java:102)
at com.example.newsreport.NewsReportActivity.onLoadFinished(NewsReportActivity.java:29)
at 安卓x.loader.app.LoaderManagerImpl$LoaderObserver.onChanged(LoaderManagerImpl.java:250)
at 安卓x.lifecycle.LiveData.considerNotify(LiveData.java:113)
我需要使用从loadimageasynctask返回的drawable 我需要存储在数据库中的所有数据以及内容提供商
# 1 楼答案
表中有4列和主键
插入新行时，为
ContentValues对象提供值，但为每列提供两次：为什么
我怀疑：
返回
null所以删除以下几行：
不需要它们
列的值由前4行设置