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：

2 
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();
        }
    }
}