android sqllite数据库crud+分页

package com.smart.service; import java.util.ArrayList; import java.util.List; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import com.smart.domain.Person; public class PersonService { /** * 这里是处理业务的方法，和JAVA叫做实现类 * 如果用上下文打开数据库，一定要关闭数据库 * */ private DataBaseOpenHelper dbOpenHelper; public PersonService(Context context) { dbOpenHelper = new DataBaseOpenHelper(context); } public void save(Person person) { SQLiteDatabase database=dbOpenHelper.getWritableDatabase(); database.execSQL("insert into person(name,age) values(?,?)",new Object[]{person.getName(),person.getAge()}); // database.close(); } public void update(Person person) { SQLiteDatabase database=dbOpenHelper.getWritableDatabase(); database.execSQL("update person set name=?,age=? where personid=?", new Object[]{person.getName(),person.getAge(),person.getPersonid()}); } public Person find(Integer id){ SQLiteDatabase database=dbOpenHelper.getWritableDatabase(); Cursor cursor= database.rawQuery("select * from person where personid=?", new String[]{String.valueOf(id)}); if(cursor.moveToNext()){ return new Person(cursor.getInt(0),cursor.getString(1),cursor.getShort(2)); } return null; } public void delete(Integer... ids) { if(ids.length>0){ StringBuilder sb=new StringBuilder(); for(Integer id:ids){ sb.append("?").append(","); } sb.deleteCharAt(sb.length()-1); SQLiteDatabase database=dbOpenHelper.getWritableDatabase(); database.execSQL("delete from person where personid in("+sb+")", (Object[])ids); } } //分页代码 public List<Person> getScrollData(int startResult, int maxResult) { List<Person> persons=new ArrayList<Person>(); SQLiteDatabase database=dbOpenHelper.getWritableDatabase(); Cursor cursor= database.rawQuery("select * from person limit ?,?", new String[]{String.valueOf(startResult),String.valueOf(maxResult)}); while(cursor.moveToNext()){ persons.add( new Person(cursor.getInt(0),cursor.getString(1), cursor.getShort(2))); } return persons; } //取得所有的条数 public long getCount() { SQLiteDatabase database=dbOpenHelper.getWritableDatabase(); Cursor cursor= database.rawQuery("select * from person ", null); if(cursor.moveToNext()){ return cursor.getLong(0); } return 0; } }