Android中使用ormlite实现持久化–HelloOrmLite

package cn.sdx.model;

import com.j256.ormlite.field.DatabaseField;

publicclass Hello {
@DatabaseField(generatedId =true)
int id;
@DatabaseField
String word;

publicHello() {
}

@Override
public StringtoString() {
StringBuilder sb =new StringBuilder();
sb.append("id=").append(id);
sb.append(" ,word=").append(word);
return sb.toString();
}

}

package cn.sdx.utils;

import java.sql.SQLException;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;


import cn.sdx.model.Hello;

import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
import com.j256.ormlite.dao.Dao;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.table.TableUtils;

publicclass DataHelper extends OrmLiteSqliteOpenHelper {

privatestaticfinal String DATABASE_NAME ="HelloOrmlite.db";
privatestaticfinalint DATABASE_VERSION =1;
private Dao<Hello, Integer> helloDao =null;

publicDataHelper(Context context) {
super(context, DATABASE_NAME,null, DATABASE_VERSION);
}

@Override
publicvoidonCreate(SQLiteDatabase db, ConnectionSource connectionSource) {
try {
TableUtils.createTable(connectionSource, Hello.class);
}catch (SQLException e) {
Log.e(DataHelper.class.getName(),"创建数据库失败", e);
e.printStackTrace();
}
}

@Override
publicvoidonUpgrade(SQLiteDatabase db, ConnectionSource connectionSource,int arg2,
int arg3) {
try {
TableUtils.dropTable(connectionSource, Hello.class,true);
onCreate(db, connectionSource);
}catch (SQLException e) {
Log.e(DataHelper.class.getName(),"更新数据库失败", e);
e.printStackTrace();
}
}

@Override
publicvoidclose() {
super.close();
helloDao =null;
}

public Dao<Hello, Integer>getHelloDataDao()throws SQLException {
if (helloDao ==null) {
helloDao = getDao(Hello.class);
}
return helloDao;
}
}

package cn.sdx;

import java.sql.SQLException;
import java.util.List;

import com.j256.ormlite.android.apptools.OrmLiteBaseActivity;
import com.j256.ormlite.dao.Dao;

import android.os.Bundle;
import android.widget.TextView;
import cn.sdx.model.Hello;
import cn.sdx.utils.DataHelper;

publicclass HelloOrmliteActivity extends OrmLiteBaseActivity<DataHelper> {
/** Called when the activity is first created. */
@Override
publicvoidonCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView tv = (TextView)this.findViewById(R.id.output);
try {
Dao<Hello, Integer> helloDao = getHelper().getHelloDataDao();
// 添加数据
for (int i =0; i <2; i++) {
Hello hello =new Hello("Hello" + i);
helloDao.create(hello);
}
tv.setText(tv.getText() +"n" +"添加数据完成");
// 查询添加的数据
List<Hello> hellos = helloDao.queryForAll();
for (Hello h : hellos) {
tv.setText(tv.getText() +"n" + h.toString());
}
// 删除数据第一条数据
helloDao.delete(hellos.get(0));
tv.setText(tv.getText() +"n" +"删除数据完成");
// 重新查询数据
hellos = helloDao.queryForAll();
for (Hello h : hellos) {
tv.setText(tv.getText() +"n" + h.toString());
}
// 修改数据
Hello h1 = hellos.get(0);
h1.setWord("这是修改过的数据");
tv.setText(tv.getText() +"n" +"修改数据完成");
helloDao.update(h1);
// 重新查询数据
hellos = helloDao.queryForAll();
for (Hello h : hellos) {
tv.setText(tv.getText() +"n" + h.toString());
}

}catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
}