运行 Android 应用程序时出现此错误：
类 [[Lmodel.Vak; 中没有字段具有 DatabaseField 注释；
我的 Vak 类有注释，所以我真的不明白为什么它仍然给我这个错误。
package model;
import com.j256.ormlite.field.DatabaseField;
import com.j256.ormlite.table.DatabaseTable;
@DatabaseTable(tableName = "vak")
public class Vak {
@DatabaseField(generatedId = true, columnName = "vakID", id=true) Long id;
@DatabaseField int rij;
@DatabaseField
int kolom;
...
}
我有一个名为 Databasehelper.java 的文件，其中扩展了 OrmLiteSqLiteOpenHelper，该文件如下所示：
public class DatabaseHelper extends OrmLiteSqliteOpenHelper {
// name of the database file for your application -- change to something
// appropriate for your app
private static final String DATABASE_NAME = "project56.db";
// any time you make changes to your database objects, you may have to
// increase the database version
private static final int DATABASE_VERSION = 1;
private DatabaseType databaseType = new SqliteAndroidDatabaseType();
// the DAO object we use to access the tables
private Dao<Vleugel, Long> vleugelDao = null;
private Dao<Verdieping, Long> verdiepingDao = null;
private Dao<NavigatiePunt, Long> navigatiePuntDao = null;
private Dao<Lokaal, Long> lokaalDao = null;
private Dao<Raster, Long> rasterDao = null;
private Dao<Vak, Long> vakDao = null;
private Dao<Graaf, Long> graafDao = null;
private Dao<Vertex, Long> vertexDao = null;
private Dao<Edge, Long> edgeDao = null;
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
/**
* This is called when the database is first created. Usually you should
* call createTable statements here to create the tables that will store
* your data.
*/
@Override
public void onCreate(SQLiteDatabase db, ConnectionSource connectionSource) {
try {
Log.i(DatabaseHelper.class.getName(), "onCreate");
TableUtils.createTable(connectionSource, Vleugel.class);
TableUtils.createTable(connectionSource, Verdieping.class);
TableUtils.createTable(connectionSource, NavigatiePunt.class);
TableUtils.createTable(connectionSource, Lokaal.class);
TableUtils.createTable(connectionSource, Raster.class);
TableUtils.createTable(connectionSource, Vak.class);
TableUtils.createTable(connectionSource, Graaf.class);
TableUtils.createTable(connectionSource, Vertex.class);
TableUtils.createTable(connectionSource, Edge.class);
} catch (SQLException e) {
Log.e(DatabaseHelper.class.getName(), "Can't create database", e);
throw new RuntimeException(e);
}
}
/**
* This is called when your application is upgraded and it has a higher
* version number. This allows you to adjust the various data to match the
* new version number.
*/
@Override
public void onUpgrade(SQLiteDatabase db, ConnectionSource connectionSource,
int oldVersion, int newVersion) {
try {
Log.i(DatabaseHelper.class.getName(), "onUpgrade");
TableUtils.dropTable(connectionSource, Vleugel.class, true);
TableUtils.dropTable(connectionSource, Verdieping.class, true);
TableUtils.dropTable(connectionSource, NavigatiePunt.class, true);
TableUtils.dropTable(connectionSource, Lokaal.class, true);
TableUtils.dropTable(connectionSource, Raster.class, true);
TableUtils.dropTable(connectionSource, Vak.class, true);
TableUtils.dropTable(connectionSource, Graaf.class, true);
TableUtils.dropTable(connectionSource, Vertex.class, true);
TableUtils.dropTable(connectionSource, Edge.class, true);
// after we drop the old databases, we create the new ones
onCreate(db, connectionSource);
} catch (SQLException e) {
Log.e(DatabaseHelper.class.getName(), "Can't drop databases", e);
throw new RuntimeException(e);
}
}
/**
* Returns the Database Access Object (DAO) for the classes It will create
* it or just give the cached value.
*/
public Dao<Vleugel, Long> getVleugelDao() throws SQLException {
if (vleugelDao == null) {
vleugelDao = getDao(Vleugel.class);
}
return vleugelDao;
}
public Dao<Verdieping, Long> getVerdiepingDao() throws SQLException {
if (verdiepingDao == null) {
verdiepingDao = getDao(Verdieping.class);
}
return verdiepingDao;
}
public Dao<NavigatiePunt, Long> getNavigatiePuntDao() throws SQLException {
if (navigatiePuntDao == null) {
navigatiePuntDao = getDao(NavigatiePunt.class);
}
return navigatiePuntDao;
}
public Dao<Lokaal, Long> getLokaalDao() throws SQLException {
if (lokaalDao == null) {
lokaalDao = getDao(Lokaal.class);
}
return lokaalDao;
}
public Dao<Raster, Long> getRasterDao() throws SQLException {
if (rasterDao == null) {
rasterDao = getDao(Raster.class);
}
return rasterDao;
}
public Dao<Vak, Long> getVakDao() throws SQLException {
if (vakDao == null) {
vakDao = getDao(Vak.class);
}
return vakDao;
}
public Dao<Graaf, Long> getGraafDao() throws SQLException {
if (graafDao == null) {
graafDao = getDao(Graaf.class);
}
return graafDao;
}
public Dao<Vertex, Long> getVertexDao() throws SQLException {
if (vertexDao == null) {
vertexDao = getDao(Vertex.class);
}
return vertexDao;
}
public Dao<Edge, Long> getEdgeDao() throws SQLException {
if (edgeDao == null) {
edgeDao = getDao(Edge.class);
}
return edgeDao;
}
/**
* Close the database connections and clear any cached DAOs.
*/
@Override
public void close() {
super.close();
vleugelDao = null;
verdiepingDao = null;
navigatiePuntDao = null;
lokaalDao = null;
rasterDao = null;
vakDao = null;
graafDao = null;
vertexDao = null;
edgeDao = null;
}
}
我还有一个扩展 OrmLiteBaseActivity 的文件控制器：
public class Controller extends OrmLiteBaseActivity<DatabaseHelper> {
Dao<Vleugel, Long> vleugelDao;
Dao<Verdieping, Long> verdiepingDao;
Dao<NavigatiePunt, Long> navigatiePuntDao;
Dao<Lokaal, Long> lokaalDao;
Dao<Raster, Long> rasterDao;
Dao<Graaf, Long> graafDao;
Dao<Vertex, Long> vertexDao;
Dao<Edge, Long> edgeDao;
Dao<Vak, Long> vakDao;
// Databasehelper is benodigd voor ORMLite
static {
OpenHelperManager.setOpenHelperFactory(new SqliteOpenHelperFactory() {
public OrmLiteSqliteOpenHelper getHelper(Context context) {
return new DatabaseHelper(context);
}
});
}
public Controller() throws SQLException {
/** initialiseren van dao */
vleugelDao = getHelper().getVleugelDao();
verdiepingDao = getHelper().getVerdiepingDao();
navigatiePuntDao = getHelper().getNavigatiePuntDao();
lokaalDao = getHelper().getLokaalDao();
rasterDao = getHelper().getRasterDao();
graafDao = getHelper().getGraafDao();
vertexDao = getHelper().getVertexDao();
edgeDao = getHelper().getEdgeDao();
vakDao = getHelper().getVakDao();
}
/**
* Haalt vleugel idNaam op uit dao object bijv. K1
*
* @return Vleugel
* @throws java.sql.SQLException
*/
public Vleugel getVleugel(String vleugelIDNaam)
throws java.sql.SQLException {
// select * from vleugel where idNaam='{vleugelIDNaam}'
QueryBuilder<Vleugel, Long> qb = vleugelDao.queryBuilder();
Where where = qb.where();
// the name field must be equal to "foo"
where.eq("idNaam", vleugelIDNaam);
PreparedQuery<Vleugel> preparedQuery = qb.prepare();
List<Vleugel> vleugelList = vleugelDao.query(preparedQuery);
Log.v("Getvleugel", vleugelList.size() + "");
if (vleugelList.size() == 1) {
return vleugelList.get(0);
}
return null;
}
public Verdieping getVerdieping(int nummer) throws java.sql.SQLException {
// TODO: Met querybuilder query naar db om verdieping te pakken
return null;
}
/**
* Haalt navigatiepunt op
*
* @param naam
* @return
* @throws java.sql.SQLException
*/
public NavigatiePunt getNavigatiePunt(String naam)
throws java.sql.SQLException {
// select * from navigatiepunt where naam='{naam}'
QueryBuilder<NavigatiePunt, Long> qb = navigatiePuntDao.queryBuilder();
Where where = qb.where();
where.eq("naam", naam);
PreparedQuery<NavigatiePunt> preparedQuery = qb.prepare();
List<NavigatiePunt> navigatieList = navigatiePuntDao
.query(preparedQuery);
Log.v("GetLokaal", navigatieList.size() + "");
if (navigatieList.size() == 1) {
return navigatieList.get(0);
}
return null;
}
/**
* Get lokaal object op basis van lokaalcode
*
* @param lokaalcode
* @return
* @throws java.sql.SQLException
*/
public Lokaal getLokaal(String lokaalcode) throws java.sql.SQLException {
// select * from lokaal where lokaalcode='{lokaalcode}'
QueryBuilder<Lokaal, Long> qb = lokaalDao.queryBuilder();
Where where = qb.where();
where.eq("lokaalcode", lokaalcode);
PreparedQuery<Lokaal> preparedQuery = qb.prepare();
List<Lokaal> lokaalList = lokaalDao.query(preparedQuery);
Log.v("GetLokaal", lokaalList.size() + "");
if (lokaalList.size() == 1) {
return lokaalList.get(0);
}
return null;
}
}
那么您对此有什么建议，我应该检查什么？