基于AndroidSQLiteOpenHelper&&CRUD的使用

public class PersonService {
 private DBOpenHelper dbOpenHelper;
 public PersonService(Context context) {
  super();
  this.dbOpenHelper = new DBOpenHelper(context, 2);
 }
 public void save(Person person) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  // SQLiteDatabase db2 = dbOpenHelper.getWritableDatabase();有缓存的功能，同一个Helper用此方法得到的对象为db;
  db.execSQL("insert into person(name,phone) values(?,?)", new Object[] {person.getName(), person.getPhone() });
 }
 public void delete(Integer id) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  db.execSQL("delete from person where persOnid=?", new Object[] { id });
 }
 public void update(Person person) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  db.execSQL("update person set name=?,phOne=? where persOnid=?",new Object[] { person.getName(), person.getPhone(),person.getId() });
 }
 public Person find(Integer id) {
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  // 如果数据库磁盘空间未满，得到的实例即为getWritableDatabase()得到的对象；因为此方法会调用getWritableDatabase方法；
  Cursor cursor = db.rawQuery("select * from person where persOnid=?",new String[] { id.toString() });
  if (cursor.moveToFirst()) {
   int persOnid= cursor.getInt(cursor.getColumnIndex("personid"));
   String name = cursor.getString(cursor.getColumnIndex("name"));
   String phOne= cursor.getString(cursor.getColumnIndex("phone"));
   return new Person(personid, name, phone);
  }
  cursor.close();
  return null;
 }
 /*
  * 获取分页数据
  */
 public List getScollData(int offest, int maxResult) {
  List persOns= new ArrayList();
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.rawQuery("select * from person order by personid asc limit ?,?",new String[] { String.valueOf(offest),String.valueOf(maxResult) });
  while (cursor.moveToNext()) {
   int persOnid= cursor.getInt(cursor.getColumnIndex("personid"));
   String name = cursor.getString(cursor.getColumnIndex("name"));
   String phOne= cursor.getString(cursor.getColumnIndex("phone"));
   persons.add(new Person(personid, name, phone));
  }
  cursor.close();
  return persons;
 }
 public long getCount() {
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.rawQuery("select count(*) from person", null);
  cursor.moveToFirst();
  long result = cursor.getLong(0);
  return result;
 }
}

public class OtherPersonService {
 private DBOpenHelper dbOpenHelper;
 public OtherPersonService(Context context) {
  super();
  this.dbOpenHelper = new DBOpenHelper(context, 2);
 }
 public void save(Person person) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  ContentValues values = new ContentValues();// ContentValues 专门用于保存字段的值
  values.put("name", person.getName());
  values.put("phone", person.getPhone());
  db.insert("person", null, values);// 第三个参数为字段值,第二个参数为空值字段，如果第三个参数为null
 }
 public void delete(Integer id) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  db.delete("person", "persOnid=?", new String[] { id.toString() });
 }
 public void update(Person person) {
  SQLiteDatabase db = dbOpenHelper.getWritableDatabase();
  ContentValues values = new ContentValues();
  values.put("name", person.getName());
  values.put("phone", person.getPhone());
  db.update("person", values, "persOnid=?", new String[] { person.getId().toString() });
 }
 public Person find(Integer id) {
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.query("person", null, "persOnid=?",new String[] { id.toString() }, null, null, null);
  if (cursor.moveToFirst()) {
   int persOnid= cursor.getInt(cursor.getColumnIndex("personid"));
   String name = cursor.getString(cursor.getColumnIndex("name"));
   String phOne= cursor.getString(cursor.getColumnIndex("phone"));
   return new Person(personid, name, phone);
  }
  cursor.close();
  return null;
 }
 /*
  * 获取分页数据
  */
 public List getScollData(int offest, int maxResult) {
  List persOns= new ArrayList();
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.query("person", null, null, null, null, null,"personid asc", offest + "," + maxResult);
                //db.query(table, columns, selection, selectionArgs, groupBy, having, orderBy, limit);
  while (cursor.moveToNext()) {
   int persOnid= cursor.getInt(cursor.getColumnIndex("personid"));
   String name = cursor.getString(cursor.getColumnIndex("name"));
   String phOne= cursor.getString(cursor.getColumnIndex("phone"));
   persons.add(new Person(personid, name, phone));
  }
  cursor.close();
  return persons;
 }
 public long getCount() {
  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();
  Cursor cursor = db.query("person", new String[] { "count(*)" }, null, null, null, null, null);
                //db.query(table, columns, selection, selectionArgs, groupBy, having, orderBy);
  cursor.moveToFirst();
  long result = cursor.getLong(0);
  return result;
 }
}