GreenDao的封装和使用

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GreenDao的封装和使用

首先先集成GreenDao，在本人博客里有GreenDao3.2的集成步骤，可参考

MainActivity

package com.example.greendaodemo;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.util.Log;import com.example.greendaodemo.bean.User;import com.example.greendaodemo.dao.MyUserDao;import java.util.List;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        MyUserDao dao = new MyUserDao(this);//        User u = new User();//        u.setAge(10);//        u.setName("22");//        u.setId("001");//        dao.insertUser(this,);        for (int i = 20; i < 25; i++) {            User user = new User();            user.setId(Long.valueOf(i));            user.setAge(i * 3);            user.setName("第" + i + "人");            dao.insertUser(user);        }        List<User> userList = dao.queryUserList();        for (User user : userList) {            Log.e("TAG", "queryUserList--before-->" + user.getId() + "--" + user.getName() +"--"+user.getAge());            if (user.getId() == 10) {                dao.deleteUser(user);            }            if (user.getId() == 13) {                user.setAge(25);                dao.updateUser(user);            }        }        userList = dao.queryUserList();        for (User user : userList) {            Log.e("TAG", "queryUserList--after--->" + user.getId() + "---" + user.getName()+"--"+user.getAge());        }    }}

GreenDao封装

package com.example.greendaodemo.db;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import com.example.greendaodemo.bean.DaoMaster;/** * Created by yfeng on 2017/11/23. * DBManager 数据库管理者 * * 获取可读或者可写的数据库对象 */public class DBManager {    private final static String dbName = "test_db";    private static DBManager mInstance;    private DaoMaster.DevOpenHelper openHelper;    private Context context;    private DBManager(Context context) {        this.context = context;        openHelper = new DaoMaster.DevOpenHelper(context, dbName, null);    }    /**     * 获取单例引用     *     * @param context     * @return     */    public static DBManager getInstance(Context context) {        if (mInstance == null) {            synchronized (DBManager.class) {                if (mInstance == null) {                    mInstance = new DBManager(context);                }            }        }        return mInstance;    }    public SQLiteDatabase getReadableDatabase() {        if (openHelper == null) {            openHelper = new DaoMaster.DevOpenHelper(context, dbName, null);        }        SQLiteDatabase db = openHelper.getReadableDatabase();        return db;    }    public SQLiteDatabase getWritableDatabase() {        if (openHelper == null) {            openHelper = new DaoMaster.DevOpenHelper(context, dbName, null);        }        SQLiteDatabase db = openHelper.getWritableDatabase();        return db;    }}

UserBean

package com.example.greendaodemo.bean;import org.greenrobot.greendao.annotation.Entity;import org.greenrobot.greendao.annotation.Id;import org.greenrobot.greendao.annotation.Property;import org.greenrobot.greendao.annotation.Generated;/** * Created by yfeng on 2017/11/23. */@Entitypublic class User {    @Id    private Long id;    @Property    private String name;    @Property    private int age;    @Generated(hash = 1309193360)    public User(Long id, String name, int age) {        this.id = id;        this.name = name;        this.age = age;    }    @Generated(hash = 586692638)    public User() {    }    public Long getId() {        return this.id;    }    public void setId(Long id) {        this.id = id;    }    public String getName() {        return this.name;    }    public void setName(String name) {        this.name = name;    }    public int getAge() {        return this.age;    }    public void setAge(int age) {        this.age = age;    }    //下面省去了 setter/getter}

UserDao

package com.example.greendaodemo.dao;import android.content.Context;import com.example.greendaodemo.db.DBManager;import com.example.greendaodemo.bean.DaoMaster;import com.example.greendaodemo.bean.DaoSession;import com.example.greendaodemo.bean.User;import com.example.greendaodemo.bean.UserDao;import org.greenrobot.greendao.query.QueryBuilder;import java.util.List;/** * Created by yfeng on 2017/11/23. */public class MyUserDao {    Context context;    public MyUserDao(Context context) {        this.context = context;    }    /**     * 插入一条记录     *     * @param user     */    public void insertUser(User user) {        DaoMaster daoMaster = new DaoMaster(DBManager.getInstance(context).getWritableDatabase());        DaoSession daoSession = daoMaster.newSession();        UserDao userDao = daoSession.getUserDao();        userDao.insert(user);    }    /**     * 插入用户集合     *     * @param users     */    public void insertUserList(List<User> users) {        if (users == null || users.isEmpty()) {            return;        }        DaoMaster daoMaster = new DaoMaster(DBManager.getInstance(context).getWritableDatabase());        DaoSession daoSession = daoMaster.newSession();        UserDao userDao = daoSession.getUserDao();        userDao.insertInTx(users);    }    /**     * 查询用户列表     */    public List<User> queryUserList() {        DaoMaster daoMaster = new DaoMaster(DBManager.getInstance(context).getReadableDatabase());        DaoSession daoSession = daoMaster.newSession();        UserDao userDao = daoSession.getUserDao();        QueryBuilder<User> qb = userDao.queryBuilder();        List<User> list = qb.list();        return list;    }    /**     * 查询用户列表     */    public List<User> queryUserList(int age) {        DaoMaster daoMaster = new DaoMaster(DBManager.getInstance(context).getReadableDatabase());        DaoSession daoSession = daoMaster.newSession();        UserDao userDao = daoSession.getUserDao();        QueryBuilder<User> qb = userDao.queryBuilder();        qb.where(UserDao.Properties.Age.gt(age)).orderAsc(UserDao.Properties.Age);        List<User> list = qb.list();        return list;    }    /**     * 更新一条记录     *     * @param user     */    public void updateUser(User user) {        DaoMaster daoMaster = new DaoMaster(DBManager.getInstance(context).getWritableDatabase());        DaoSession daoSession = daoMaster.newSession();        UserDao userDao = daoSession.getUserDao();        userDao.update(user);    }    /**     * 删除一条记录     *     * @param user     */    public void deleteUser(User user) {        DaoMaster daoMaster = new DaoMaster(DBManager.getInstance(context).getWritableDatabase());        DaoSession daoSession = daoMaster.newSession();        UserDao userDao = daoSession.getUserDao();        userDao.delete(user);    }}

运行结果

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