/*
* Copyright (C) 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package uni.projecte.dataLayer.bd;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
/**
* Simple notes database access helper class. Defines the basic CRUD operations
* for the notepad example, and gives the ability to list all notes as well as
* retrieve or modify a specific note.
*
* This has been improved from the first version of this tutorial through the
* addition of better error handling and also using returning a Cursor instead
* of using a collection of inner classes (which is less scalable and not
* recommended).
*/
public class ItemDTDbAdapter {
public static final String KEY_ROWID = "_id";
public static final String DT_ID ="idDT";
public static final String ITEM_NAME="itemName";
public static final String ITEM_INFO="itemInfo";
private static final String TAG = "ItemsDTDbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
/**
* Database creation sql statement
*/
private static final String DATABASE_CREATE =
"create table ItemDT ("
+ KEY_ROWID + " INTEGER PRIMARY KEY,"
+ DT_ID+ " INTEGER,"
+ ITEM_NAME + " TEXT,"
+ ITEM_INFO + " TEXT"
+ ");";
private static final String DATABASE_NAME = "mobileSamplingItem";
private static final String DATABASE_TABLE = "ItemDT";
private static final int DATABASE_VERSION = 2;
private final Context mCtx;
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public void onCreate(SQLiteDatabase db) {
db.execSQL(DATABASE_CREATE);
}
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS notes");
onCreate(db);
}
}
/**
* Constructor - takes the context to allow the database to be
* opened/created
*
* @param ctx the Context within which to work
*/
public ItemDTDbAdapter(Context ctx) {
this.mCtx = ctx;
}
/**
* Open the notes database. If it cannot be opened, try to create a new
* instance of the database. If it cannot be created, throw an exception to
* signal the failure
*
* @return this (self reference, allowing this to be chained in an
* initialization call)
* @throws SQLException if the database could be neither opened or created
*/
public ItemDTDbAdapter open() throws SQLException {
mDbHelper = new DatabaseHelper(mCtx);
mDb = mDbHelper.getWritableDatabase();
return this;
}
public void close() {
mDbHelper.close();
}
/**
* Create a new ItemDT using the name, idDT and the info. If the ItemDT is
* successfully created return the new rowId for that ItemDT, otherwise return
* a -1 to indicate failure.
*
* @param itemName the name of the ItemDT
* @param idDT the DT identificator of the ItemDT
* @param itemInfo the info of the ItemDT
* @return rowId or -1 if failed
*/
public long addItemDT(int dtNum, String itemName, String itemInfo) {
ContentValues initialValues = new ContentValues();
initialValues.put(DT_ID, dtNum);
initialValues.put(ITEM_NAME , itemName);
initialValues.put(ITEM_INFO, itemInfo);
return mDb.insert(DATABASE_TABLE, null, initialValues);
}
/**
* Delete the ItemDT with the given rowId
*
* @param rowId id of ItemDT to delete
* @return true if deleted, false otherwise
*/
public boolean deleteItemDT(long rowId) {
return mDb.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
/**
* Return a Cursor over the list of all items DT in the database
*
* @return Cursor over all items
*/
public Cursor fetchAllDtItems() {
return mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, DT_ID,
ITEM_NAME,ITEM_INFO}, null, null, null, null, null);
}
/**
* Return a Cursor positioned at the itemDT that matches the given DT id
*
* @param type of note to retrieve
* @return Cursor positioned to matching note, if found
* @throws SQLException if note could not be found/retrieved
*/
public Cursor fetchDtItembyType(long type) throws SQLException {
return mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, DT_ID,
ITEM_NAME,ITEM_INFO}, DT_ID + "=" + type, null, null, null, null);
}
}
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