关系数据库ORMlite的用法；

首先要在 http://ormlite.com/releases 页面下载两个jar 包：

（1）core列表下的jar包； （2）android列表下的jar包。

将上面的两个jar包下载后放到Android工程项目中的libs包中。

在创建一个java类来存放数据，

 1 package zhangphil.ormlitetest.database;
 2
 3 import com.j256.ormlite.field.DatabaseField;
 4 import com.j256.ormlite.table.DatabaseTable;
 5
 6 @DatabaseTable(tableName = "users")
 7 public class User {
 8
 9     public final static String USER_ID = "user_id";
10     public final static String NAME = "name";
11     public final static String AGE = "age";
12
13     public User() {
14
15     }
16
17     public User(String name, int age) {
18         this.name = name;
19         this.age = age;
20     }
21
22     // @DatabaseField(generatedId = true)
23     // public int id;
24
25     @DatabaseField(id = true, columnName = USER_ID)
26     public int user_id;
27
28     @DatabaseField(columnName = NAME)
29     public String name;
30
31     @DatabaseField(columnName = AGE)
32     public int age;
33
34     public int getUserId() {
35         return user_id;
36     }
37
38     public void setUserId(int uid) {
39         this.user_id = uid;
40     }
41
42     public String getName() {
43         return name;
44     }
45
46     public void setName(String name) {
47         this.name = name;
48     }
49
50     public int getAge() {
51         return age;
52     }
53
54     public void setAge(int age) {
55         this.age = age;
56     }
57
58     @Override
59     public String toString() {
60         return "user_id:" + user_id + " 姓名:" + name + " 年龄:" + age;
61     }
62 }

创建一个ORMLite数据库管理工具类：

 import java.sql.SQLException;

 import android.content.Context;
 import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteDatabase.CursorFactory;
 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;

 public class ORMLiteDatabaseHelper extends OrmLiteSqliteOpenHelper {

     private static ORMLiteDatabaseHelper mDatabaseHelper = null;
     private Dao<User, Integer> mUserDao = null;

     private final static String DataBase_NAME = "ormlite.db";
     private final static int DataBase_VERSION = 1;

     public ORMLiteDatabaseHelper(Context context, String databaseName,
             CursorFactory factory, int databaseVersion) {
         super(context, DataBase_NAME, factory, DataBase_VERSION);
     }

     public static ORMLiteDatabaseHelper getInstance(Context context) {
         if (mDatabaseHelper == null) {
             mDatabaseHelper = new ORMLiteDatabaseHelper(context, DataBase_NAME,
                     null, DataBase_VERSION);
         }

         return mDatabaseHelper;
     }

     @Override
     public void onCreate(SQLiteDatabase arg0, ConnectionSource connectionSource) {

         Log.d(this.getClass().getName(), "ORMLite数据库 -> onCreate");

         try {
             TableUtils.createTableIfNotExists(connectionSource, User.class);
         } catch (Exception e) {
             e.printStackTrace();
         }
     }

     @Override
     public void onUpgrade(SQLiteDatabase database, ConnectionSource arg1,
             int arg2, int arg3) {

         Log.i(this.getClass().getName(), "数据库 -> onUpgrade");

         try {
             // 删除旧的数据库表。
             TableUtils.dropTable(connectionSource, User.class, true);

             // 重新创建新版的数据库。
             onCreate(database, connectionSource);
         } catch (SQLException e) {
             e.printStackTrace();
         }
     }

     /**
      * 每一个数据库中的表，要有一个获得Dao的方法。 可以使用一种更通用的模板方法如：
      *
      * public Dao<Class, Integer> getORMLiteDao(Class cls) throws SQLException {
      * if (dao == null) { dao = getDao(cls); }
      *
      * return dao; }
      */
     public Dao<User, Integer> getUserDao() {
         if (mUserDao == null) {
             try {
                 mUserDao = getDao(User.class);
             } catch (java.sql.SQLException e) {
                 e.printStackTrace();
             }
         }

         return mUserDao;
     }

     @Override
     public void close() {
         super.close();
         mUserDao = null;
     }
 }

最后在mainactivity中操作添加数据：

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

 import com.j256.ormlite.dao.Dao;

 import zhangphil.ormlitetest.database.ORMLiteDatabaseHelper;
 import zhangphil.ormlitetest.database.User;
 import android.support.v7.app.ActionBarActivity;
 import android.widget.Toast;
 import android.os.Bundle;

 public class MainActivity extends ActionBarActivity {

     private Dao<User, Integer> mUserDao;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         ORMLiteDatabaseHelper mDatabaseHelper = ORMLiteDatabaseHelper
                 .getInstance(this);
         mUserDao = mDatabaseHelper.getUserDao();

         Random rand = new Random();
         for (int i = 0; i < 3; i++) {
             User user = new User();
             user.setUserId(i);
             user.setName("name" + i);
             // 生成随机测试的年龄。
             user.setAge(rand.nextInt(100));

             try {
                 mUserDao.createOrUpdate(user);
             } catch (SQLException e) {
                 e.printStackTrace();
             }
         }
     }

     @Override
     public void onStart() {
         super.onStart();

         // 全局查询
         try {
             List<User> users = mUserDao.queryForAll();

             for (User u : users) {
                 Toast.makeText(this, u.toString(), Toast.LENGTH_SHORT).show();
             }
         } catch (SQLException e) {
             e.printStackTrace();
         }

         // 条件查询QueryBuilder
         // 假设我们给定一个用户的id=1
         int uid = 1;
         try {
             List<User> users = mUserDao.queryBuilder().where()
                     .eq(User.USER_ID, uid).query();

             for (User u : users) {
                 Toast.makeText(this, "查询结果 : " + u.toString(),
                         Toast.LENGTH_SHORT).show();
             }
         } catch (SQLException e) {
             e.printStackTrace();
         }
     }
 }