android开发中类似hibernate的orm框架-ormlite
为框架挂了，这个问题调了一上午
/**
* 一定要在close方法中这里把Dao指向null，不然会出现Most one of id,generatedId,generatedIdSequence
*/
@Override
public void close() {
// TODO Auto-generated method stub
super.close();
specialtyDao = null;
doctorDao = null;
departmentDao = null;
departDoctorDao = null;
}
官网上面有hellodemo，可以用jpa也可以用raw下面的txt文件配置。
DBHelper类:
1.需要继承OrmLiteSqliteOpenHelper类;
2.里面还有一个Dao<Hello,Integer> hellodao的引用数据域变量；
3.需要重写三个方法onCreate，onUpgrade，close;还需要添加hellodao的引用数据域变量的getHelloDao()方法;
package com.zyl.ormLiteDemo;
import java.sql.SQLException;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
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;
import com.zyl.ormLiteDemo.pojo.Hello2;
public class DBHelper extends OrmLiteSqliteOpenHelper {
private final static String DATABASE_NAME = "MyDB.db";
private final static int DATABASE_VERSION = 1;
/**
* dao引用
*/
private Dao<Hello2, Integer> hello2dao = null;
public DBHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
}
@Override
public void onCreate(SQLiteDatabase db, ConnectionSource connectionSource) {
// TODO Auto-generated method stub
try {
TableUtils.createTable(connectionSource, Hello2.class);
} catch (SQLException e) {
Log.e(DBHelper.class.getName(), "创建数据库失败", e);
e.printStackTrace();
}
}
@Override
public void onUpgrade(SQLiteDatabase db, ConnectionSource connectionSource, int arg2,
int arg3) {
// TODO Auto-generated method stub
try {
TableUtils.dropTable(connectionSource, Hello2.class, true);
onCreate(db, connectionSource);
} catch (SQLException e) {
// TODO Auto-generated catch block
Log.e(DBHelper.class.getName(), "更新数据库失败", e);
e.printStackTrace();
}
}
@Override
public void close() {
// TODO Auto-generated method stub
super.close();
hello2dao = null;
}
/**
*
* @Title: getHello2Dao
* @Description: TODO(获得dao的调用方法)
* @return
* @throws SQLException 设定文件
* @return Dao<Hello2,Integer> 返回类型
*/
public Dao<Hello2,Integer> getHello2Dao() throws SQLException{
if (hello2dao == null) {
hello2dao = getDao(Hello2.class);
}
return hello2dao;
}
}
Hello2类：
可以用注解来映射，但必须保留Bean的无参数构造器；
package com.zyl.ormLiteDemo.pojo;
import com.j256.ormlite.field.DatabaseField;
public class Hello2 {
@DatabaseField(generatedId=true)
private int id;
@DatabaseField
private String word;
public Hello2() {
super();
// TODO Auto-generated constructor stub
}
public Hello2(String word){
this.word = word;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getWord() {
return word;
}
public void setWord(String word) {
this.word = word;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("id=").append(id);
sb.append(" ,word=").append(word);
return sb.toString();
}
}
Activity类：
有两种方式：一种是继承OrmLiteBaseActivity类，就可以直接使用getHelper()方法无需直接自己写；
另外一种是还是继承Android的Activity类，但需要自己提供getHelper()方法；
下为第二种：
package com.zyl.ormLiteDemo;
import java.sql.SQLException;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import com.j256.ormlite.android.apptools.OpenHelperManager;
import com.j256.ormlite.dao.Dao;
import com.zyl.ormLiteDemo.pojo.Hello2;
/**
*
* @ClassName: OrmLiteTest
* @Description: TODO(测试OrmLite框架类)
* @author zyl
* @date 2012-6-8 下午7:30:12
*/
public class OrmLiteTest extends Activity {
private DBHelper dbHelper = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TextView tv = (TextView) findViewById(R.id.output);
try {
Dao<Hello2,Integer> hello2dao = getHelper().getHello2Dao();
for (int i = 0; i < 2; i++) {
Hello2 hello2 = new Hello2("Hello2" + i);
hello2dao.create(hello2);//添加数据
tv.setText(tv.getText() + "\n" + "添加数据完成");
}
} catch (SQLException e) {
Log.e(OrmLiteTest.class.getName(), "获取hello2Dao失败", e);
e.printStackTrace();
}
}
@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
if (dbHelper != null) {
OpenHelperManager.releaseHelper();
dbHelper = null;
}
}
/**
*
* @Title: getHelper
* @Description: TODO(获得自定义数据库小助手类DBHelper)
* @return 设定文件
* @return DBHelper 返回类型
*/
public DBHelper getHelper(){
if (dbHelper == null) {
dbHelper = OpenHelperManager.getHelper(this, DBHelper.class);
}
return dbHelper;
}
}
第一种：
package com.zyl.ormLiteDemo;
import java.sql.SQLException;
import java.util.List;
import android.os.Bundle;
import android.widget.TextView;
import com.j256.ormlite.android.apptools.OrmLiteBaseActivity;
import com.j256.ormlite.dao.Dao;
import com.zyl.ormLiteDemo.pojo.Hello;
public class OrmliteLoginActivity extends OrmLiteBaseActivity<DataHelper>
{
@Override
public void onCreate(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();
}
}
}
参考1：http://chennaigong.iteye.com/blog/1161867
官方网站：http://ormlite.com/