GreenDao 3.2版本入门 以及实例讲解

一: 依赖

app//build.gradle  :

apply plugin: 'org.greenrobot.greendao'

android{

greendao {
    schemaVersion 1
    daoPackage 'com.zgl.greentest.gen'
    targetGenDir 'src/main/java'

}

}

dependencies{

compile 'org.greenrobot:greendao-generator:3.2.2'
compile 'org.greenrobot:greendao:3.2.2'

}

project// build.gradle:

buildscript {
    repositories {

        mavenCentral()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.3.1'
        classpath 'org.greenrobot:greendao-gradle-plugin:3.2.1'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

二 在项目包下创建实体类(我是在db包里面写的OnlinePlayListBean)

@Entity@Keep
public class OnlinePlayListBean {
    @Id
    private long playListId;
    @Property(nameInDb = "_data")
    private String localUrl;
    @Property(nameInDb = "name")
    private String listName;

    @Property(nameInDb = "date_added")
    private long addDate;
    @Property(nameInDb = "date_modified")
    private long modifiedDate;


    public OnlinePlayListBean(long playListId, String listName, String localUrl, long addDate, long modifiedDate) {
        this.playListId = playListId;
        this.listName = listName;
        this.localUrl = localUrl;
        this.addDate = addDate;
        this.modifiedDate = modifiedDate;
    }


    //primary

    public long getPlayListId() {
        return playListId;
    }

    public void setPlayListId(long playListId) {
        this.playListId = playListId;
    }

    public String getListName() {
        return listName;
    }

    public void setListName(String listName) {
        this.listName = listName;
    }

    public String getLocalUrl() {
        return localUrl;
    }

    public void setLocalUrl(String localUrl) {
        this.localUrl = localUrl;
    }

    public long getAddDate() {
        return addDate;
    }

    public void setAddDate(long addDate) {
        this.addDate = addDate;
    }

    public long getModifiedDate() {
        return modifiedDate;
    }

    public void setModifiedDate(long modifiedDate) {
        this.modifiedDate = modifiedDate;
    }
}

@Entity表示这个实体类会在数据库中生成对应的表，
@Id表示该字段是id，注意该字段的数据类型为包装类型Long
@Property则表示该属性将作为表的一个字段，其中nameInDb看名字就知道这个属性在数据库中对应的数据名称。

运行将项目进行编译，编译成功之后系统会帮助我们生成相应的构造方法和get/set方法，并且还会在我们的包下生成DaoMaster和DaoSession。那么这里常用的注解除了这几个之外，还有一个较常用的就是@Transient，该注解表示这个属性将不会作为数据表中的一个字段。就是这么简单。另外还有一些比如@NotNull表示该字段不可以为空，@Unique表示该字段唯一。这里的注解还是挺多的.

 

GreenDao的初始化:

public class GreenDaoManager {


    private DaoMaster mDaoMaster;
    private DaoSession mDaoSession;
    private static GreenDaoManager mInstance; //单例

    private GreenDaoManager(){
        if (mInstance == null) {
            DaoMaster.DevOpenHelper devOpenHelper = new

                    DaoMaster.DevOpenHelper(App.getContext(), "user1-db", null);//此处为自己需要处理的表

            Log.d("green dao manager???", "GreenDaoManager:  app context?"+App.getContext());
             mDaoMaster = new DaoMaster(devOpenHelper.getWritableDatabase());
            mDaoSession = mDaoMaster.newSession();
        }
    }

    public static GreenDaoManager getInstance() {
        if (mInstance == null) {
            synchronized (GreenDaoManager.class) {//保证异步处理安全操作

                if (mInstance == null) {
                    mInstance = new GreenDaoManager();
                }
            }
        }
        return mInstance;
    }

    public DaoMaster getMaster() {
        return mDaoMaster;
    }
    public DaoSession getSession() {
        return mDaoSession;
    }
    public DaoSession getNewSession() {
        mDaoSession = mDaoMaster.newSession();
        return mDaoSession;
    }



}

在App的配置

public class App extends Application {

    private static Context mContext;
   
    @Override
    public void onCreate() {
        super.onCreate();
        mContext = getApplicationContext();

        //greenDao全局配置,只希望有一个数据库操作对象
        GreenDaoManager.getInstance();

        // Set up Crashlytics, disabled for debug builds
        Crashlytics crashlyticsKit = new Crashlytics.Builder()
                .core(new CrashlyticsCore.Builder().disabled(BuildConfig.DEBUG).build())
                .build();
        Fabric.with(this, crashlyticsKit);

        //Set up dynamic shortcuts
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N_MR1) {
            new DynamicShortcutManager(this).initDynamicShortcuts();
        }
    }


    public static Context getContext() {

        return mContext;
    }


    


}

好了, 我们配置的差不多了 ,现在可以使用了:  可以在一个工具类里面写

//返回数据库操作对象

public static OnlinePlayListBeanDao getOnlinePlayListBeanDao() {

    return GreenDaoManager.getInstance().getSession().getOnlinePlayListBeanDao();
}

以下是本人在项目和文献中使用过的一些方法 比如:

    //搜id对应的信息
    public static void getOnlinePlayListBeanById() {
        OnlinePlayListBean OnlinePlayListBean = getOnlinePlayListBeanDao().load(1l);
        Log.i("tag", "结果：" + OnlinePlayListBean.getPlayListId() + "," + OnlinePlayListBean.getLocalUrl() + ","
                + OnlinePlayListBean.getListName() + "," + OnlinePlayListBean.getAddDate() + ","
                + OnlinePlayListBean.getModifiedDate());


    }


    //way : add  a  bean  directly  by watch out  the  primary key  not duplicated
    public static void insertdata() {
        //插入数据    long1:id ,long2:add_date , long3:modify_date
        OnlinePlayListBean insertData = new OnlinePlayListBean(2050, "要插入的表名", "存储位置", 20170428, 20170429);
        getOnlinePlayListBeanDao().insert(insertData);
    }

    //way: add  a bean directly   identified   by the  exist  primary key
    public static void updatadata() {
        //更改数据
        int updatePostion = 0;
        List OnlinePlayListBeanss = getOnlinePlayListBeanDao().loadAll();
        OnlinePlayListBean OnlinePlayListBean = new OnlinePlayListBean(OnlinePlayListBeanss.get(updatePostion).getPlayListId(), "更改后的数据用户", "存储位置", 20170428, 20170429);
        getOnlinePlayListBeanDao().update(OnlinePlayListBean);

    }
    //query all   by  for  loop

    public static List querydata() {
        //查询数据详细
        List onlinePlayListBeans = getOnlinePlayListBeanDao().loadAll();
        Log.i("tag", "当前数量：" + onlinePlayListBeans.size());
        for (int i = 0; i < onlinePlayListBeans.size(); i++) {
            Log.i("tag", "结果：" + onlinePlayListBeans.get(i).getPlayListId() + "," + onlinePlayListBeans.get(i).getListName() + ","
                    + onlinePlayListBeans.get(i).getLocalUrl() + "," + onlinePlayListBeans.get(i).getAddDate() + ","
                    + onlinePlayListBeans.get(i).getModifiedDate() + ";");
        }

        return  onlinePlayListBeans;
    }


    //以listname来查询
    public static void querydataBy() {////查询条件
        Query nQuery = getOnlinePlayListBeanDao().queryBuilder()
//                .where(OnlinePlayListBeanDao.Properties.Name.eq("OnlinePlayListBean1"))//.where(OnlinePlayListBeanDao.Properties.Id.notEq(999))
                .orderAsc(OnlinePlayListBeanDao.Properties.ListName)//.limit(5)//orderDesc
                .build();
        List OnlinePlayListBeans = nQuery.list();
        Log.i("tag", "当前数量：" + OnlinePlayListBeans.size());
        for (int i = 0; i < OnlinePlayListBeans.size(); i++) {
            Log.i("tag", "结果：" + OnlinePlayListBeans.get(i).getPlayListId() + "," + OnlinePlayListBeans.get(i).getListName() + ","
                    + OnlinePlayListBeans.get(i).getLocalUrl() + "," + OnlinePlayListBeans.get(i).getModifiedDate() + ","
                    + OnlinePlayListBeans.get(i).getAddDate() + ";");
        }

//        QueryBuilder qb = OnlinePlayListBeanDao.queryBuilder();
//        qb.where(Properties.FirstName.eq("Joe"),
//                qb.or(Properties.YearOfBirth.gt(1970),
//                        qb.and(Properties.YearOfBirth.eq(1970), Properties.MonthOfBirth.ge(10))));
//        List youngJoes = qb.list();
    }


    /**
     * 根据查询条件,返回数据列表
     *
     * @param where  条件
     * @param params 参数
     * @return 数据列表
     */
    public static List queryN(String where, String... params) {
        return getOnlinePlayListBeanDao().queryRaw(where, params);
    }

    /**
     * 根据用户信息,插件或修改信息
     *
     * @param OnlinePlayListBean 用户信息
     * @return 插件或修改的用户id
     */
    public static long saveN(OnlinePlayListBean OnlinePlayListBean) {
        return getOnlinePlayListBeanDao().insertOrReplace(OnlinePlayListBean);
    }

    /**
     * 批量插入或修改用户信息
     *
     * @param list 用户信息列表  根据id 修正表
     */
    public static void saveNLists(final List list) {
        if (list == null || list.isEmpty()) {
            return;
        }
        getOnlinePlayListBeanDao().getSession().runInTx(new Runnable() {
            @Override
            public void run() {
                for (int i = 0; i < list.size(); i++) {
                    OnlinePlayListBean OnlinePlayListBean = list.get(i);
                    getOnlinePlayListBeanDao().insertOrReplace(OnlinePlayListBean);
                }
            }
        });

    }

    /**
     * 删除所有数据
     */
    public static void deleteAllNote() {
        getOnlinePlayListBeanDao().deleteAll();
    }

    /**
     * 根据用户类,删除信息
     * 

     * 删除传入的实际参数bean对象
     *
     * @param OnlinePlayListBean 用户信息类
     */
    public static void deleteNote(OnlinePlayListBean OnlinePlayListBean) {
        getOnlinePlayListBeanDao().delete(OnlinePlayListBean);
    }

按id是否为某个数字时候查询:  unique() 返回一个或者0个对象 ,  uniqueOrThrow 返回一个对象否则抛出异常

 list() 返回多个对象

OnlinePlayListBean defalutOnlinePlayListBean = OnlinePlayListBeanDaoUtils.getOnlinePlayListBeanDao().queryBuilder()
        .where(OnlinePlayListBeanDao.Properties.PlayListId.eq(446623648)).unique();

添加数据 以Bean的形式

OnlinePlayListBean insertData = new OnlinePlayListBean(playlistId, charSequence.toString(), "pco", playlistId, playlistId);
OnlinePlayListBeanDaoUtils.getOnlinePlayListBeanDao().insert(insertData);

GreenDao  常见错误 解析:

1.  Caused by: java.lang.ClassNotFoundException: Didn't find class  xxx  on path: DexPathList

相关类没有混淆: 混淆时候 把相关包 按以下格式    其实class genre 是父级包

-keep public class genre.**{*;}

2.    

Error:Execution failed  for  task  ':platform:greendao' .
> Can't replace field in /Users/dsx/Documents/XXX/platform/src/main/java/com/XXX/platform/bean/OrderXXX.java: 43  with generated version. //董铂然 博客园
                      If you would like to keep it, it should be explicitly marked with  @Keep  annotation.
                      Otherwise please mark it with  @Generated  annotation

没有使用@keep 注解或者@Generated注解   视乎你有没有更改greendao 实体类 而选择注解关键字

3.

android.database.sqlite.SQLiteException: table has no column named (code 1)，

其实是修改了在创建表的内容，你只要 升级数据库版本或者卸载当前的应用 ，然后在运行加载，就不会报这个错误了。