[置顶] android orm映射框架（类似hibernate）基本使用

android  orm映射框架，可像hibernate一样操作数据库。  以下代码是我从网上摘录下来的，仅供参考.

 package com.cng.utils;

 import java.sql.SQLException;

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

 import com.cng.modal.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;

 public class DataHelper extends OrmLiteSqliteOpenHelper
 {

     private static final String DATABASE_NAME = "HelloOrmlite.db";
     private static final int DATABASE_VERSION = 1;
     private Dao<Hello, Integer> helloDao = null;

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

     @Override
     public void onCreate(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
     public void onUpgrade(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
     public void close()
     {
         super.close();
         helloDao = null;
     }

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

 

 package com.cng;

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

 import com.cng.modal.Hello;
 import com.cng.utils.DataHelper;
 import com.j256.ormlite.android.apptools.OrmLiteBaseActivity;
 import com.j256.ormlite.dao.Dao;

 import android.os.Bundle;
 import android.widget.TextView;




 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();
         }

     }
 }

 

 package com.cng.modal;

 import android.R.integer;

 import com.j256.ormlite.field.DatabaseField;

 public class Hello
 {
     @DatabaseField(generatedId = true,unique=true)
     int id;
     @DatabaseField
     String word;
     //这是必须加的，否则会出错
     public Hello(){}
     public int getId()
     {
         return id;
     }
     public Hello(String word)
     {
         super();
         this.word = word;
     }
     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();
     }

 }

 

 

就这三个类，datahelper是操作数据库的类，可新建，更新表，Hello是一个映射到数据库表的类，具体的看api  文档的下载地址是http://ormlite.com/releases/(其中的jar包也在这里下载)   OrmliteLoginActivity就是activity类，它没继承activity，而是继承了OrmLiteBaseActivity类。