android greenDao3.2.2存储数据
16lz
2021-01-23
android使用greenDao3.2.2存储数据
1、greenDao的源码和地址
官网地址：http://greenrobot.org/greendao/
github：https://github.com/greenrobot/greenDAO
参考介绍：https://www.cnblogs.com/whoislcj/p/5651396.html
2、android studio集成greenDao
Project下的build.gradle:
dependencies {
classpath 'org.greenrobot:greendao-gradle-plugin:3.2.2'
}
APP的build.gradle:
apply plugin: 'org.greenrobot.greendao'
android {
greendao {
schemaVersion 3
daoPackage 'com.safe.ticketing.greendao.gen'
targetGenDir 'src/main/java'
}
}
dependencies {
implementation 'org.greenrobot:greendao:3.2.2'
}
3、app代码部分：
DBManager.java 实例化 SQLiteOpenHelper 单利：
/** * FileName: DBManager * Author: bai * Date: 2019/4/12 9:40 */public class DBManager { private final static String dbName = "ticketing_db"; private static DBManager mInstance=null; private MSQLiteOpenHelper openHelper; private Context context; /** * 初始化数据库构造方法 * @param context Context */ private DBManager(Context context) { this.context = context; openHelper = new MSQLiteOpenHelper(context, dbName, null); } /** * 获取单例引用 * * @param context Context * @return DBManager */ public static DBManager getInstance(Context context) { if (mInstance == null) { synchronized (DBManager.class) { if (mInstance == null) { mInstance = new DBManager(context); } } } return mInstance; } /** * 获取可读数据库 */ public SQLiteDatabase getReadableDatabase() { if (openHelper == null) { openHelper = new MSQLiteOpenHelper(context, dbName, null); } return openHelper.getReadableDatabase(); } /** * 获取可写数据库 */ public SQLiteDatabase getWritableDatabase() { if (openHelper == null) { openHelper = new MSQLiteOpenHelper(context, dbName, null); } return openHelper.getWritableDatabase(); }}
LoginBean.java 要添加到数据库的字段bean：/** * FileName: LoginBean * Author: bai * Date: 2019/4/12 9:34 */@Entitypublic class LoginBean { private String userName; private String password; private String telPhone; public String getTelPhone() { return telPhone; } public void setTelPhone(String telPhone) { this.telPhone = telPhone; } @Generated(hash = 1741451137) public LoginBean(String userName, String password, String telPhone) { this.userName = userName; this.password = password; this.telPhone = telPhone; } @Generated(hash = 1112702939) public LoginBean() { } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; }}LoginDao.java 处理增删改查：/** * FileName: LoginDao * Author: bai * Date: 2019/4/12 10:20 */public class LoginDao { private DBManager dbManager = null; /** * 初始化数据库构造方法 * @param context Context */ public LoginDao(Context context) { dbManager = DBManager.getInstance(context); } /** * 插入一条记录 * * @param loginBean LoginBean */ public void insertLoginBean(LoginBean loginBean) { com.safe.ticketing.greendao.gen.DaoMaster daoMaster = new DaoMaster(dbManager.getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); LoginBeanDao loginBeanDao = daoSession.getLoginBeanDao(); loginBeanDao.insert(loginBean); } /** * 插入用户集合 * * @param loginBeans List */ public void insertLoginList(List loginBeans) { if (loginBeans == null || loginBeans.isEmpty()) { return; } DaoMaster daoMaster = new DaoMaster(dbManager.getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); LoginBeanDao loginBeanDao = daoSession.getLoginBeanDao(); loginBeanDao.insertInTx(loginBeans); } /** * 删除一条记录 * * @param loginBean LoginBean */ public void deleteLogin(LoginBean loginBean) { DaoMaster daoMaster = new DaoMaster(dbManager.getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); LoginBeanDao loginBeanDao = daoSession.getLoginBeanDao(); loginBeanDao.delete(loginBean); } /** * 更新一条记录 * * @param loginBean LoginBean */ public void updateLogin(LoginBean loginBean) { DaoMaster daoMaster = new DaoMaster(dbManager.getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); LoginBeanDao loginBeanDao = daoSession.getLoginBeanDao(); loginBeanDao.update(loginBean); } /** * 查询用户列表 */ public List queryLoginList() { DaoMaster daoMaster = new DaoMaster(dbManager.getReadableDatabase()); DaoSession daoSession = daoMaster.newSession(); LoginBeanDao loginBeanDao = daoSession.getLoginBeanDao(); QueryBuilder qb = loginBeanDao.queryBuilder(); List list = qb.list(); return list; } /** * 查询用户列表 */ public List queryLoginList(String userName) { DaoMaster daoMaster = new DaoMaster(dbManager.getReadableDatabase()); DaoSession daoSession = daoMaster.newSession(); LoginBeanDao loginBeanDao = daoSession.getLoginBeanDao(); QueryBuilder qb = loginBeanDao.queryBuilder(); qb.where(LoginBeanDao.Properties.UserName.gt(userName)).orderAsc(LoginBeanDao.Properties.UserName); List list = qb.list(); return list; }}
MigrationHelper2.java 、MSQLiteOpenHelper.java 数据库升级的处理（也就是数据库表添加新的字段或者删除后，gradle版本号+1时处理）** * FileName: MigrationHelper2 * Author: bai * Date: 2019/4/12 14:16 */public class MigrationHelper2 { public static boolean DEBUG = false; private static String TAG = "MigrationHelper2"; private static final String SQLITE_MASTER = "sqlite_master"; private static final String SQLITE_TEMP_MASTER = "sqlite_temp_master"; public static void migrate(SQLiteDatabase db, Class<? extends AbstractDao<?, ?>>... daoClasses) { printLog("【The Old Database Version】" + db.getVersion()); Database database = new StandardDatabase(db); migrate(database, daoClasses); } public static void migrate(Database database, Class<? extends AbstractDao<?, ?>>... daoClasses) { printLog("【Generate temp table】start"); generateTempTables(database, daoClasses); printLog("【Generate temp table】complete"); dropAllTables(database, true, daoClasses); createAllTables(database, false, daoClasses); printLog("【Restore data】start"); restoreData(database, daoClasses); printLog("【Restore data】complete"); } private static void generateTempTables(Database db, Class<? extends AbstractDao<?, ?>>... daoClasses) { for (int i = 0; i < daoClasses.length; i++) { String tempTableName = null; DaoConfig daoConfig = new DaoConfig(db, daoClasses[i]); String tableName = daoConfig.tablename; if (!isTableExists(db, false, tableName)) { printLog("【New Table】" + tableName); continue; } try { tempTableName = daoConfig.tablename.concat("_TEMP"); StringBuilder dropTableStringBuilder = new StringBuilder(); dropTableStringBuilder.append("DROP TABLE IF EXISTS ").append(tempTableName).append(";"); db.execSQL(dropTableStringBuilder.toString()); StringBuilder insertTableStringBuilder = new StringBuilder(); insertTableStringBuilder.append("CREATE TEMPORARY TABLE ").append(tempTableName); insertTableStringBuilder.append(" AS SELECT * FROM ").append(tableName).append(";"); db.execSQL(insertTableStringBuilder.toString()); printLog("【Table】" + tableName +"\n ---Columns-->"+getColumnsStr(daoConfig)); printLog("【Generate temp table】" + tempTableName); } catch (SQLException e) { Log.e(TAG, "【Failed to generate temp table】" + tempTableName, e); } } } private static boolean isTableExists(Database db, boolean isTemp, String tableName) { if (db == null || TextUtils.isEmpty(tableName)) { return false; } String dbName = isTemp ? SQLITE_TEMP_MASTER : SQLITE_MASTER; String sql = "SELECT COUNT(*) FROM " + dbName + " WHERE type = ? AND name = ?"; Cursor cursor=null; int count = 0; try { cursor = db.rawQuery(sql, new String[]{"table", tableName}); if (cursor == null || !cursor.moveToFirst()) { return false; } count = cursor.getInt(0); } catch (Exception e) { e.printStackTrace(); } finally { if (cursor != null) cursor.close(); } return count > 0; } private static String getColumnsStr(DaoConfig daoConfig) { if (daoConfig == null) { return "no columns"; } StringBuilder builder = new StringBuilder(); for (int i = 0; i < daoConfig.allColumns.length; i++) { builder.append(daoConfig.allColumns[i]); builder.append(","); } if (builder.length() > 0) { builder.deleteCharAt(builder.length() - 1); } return builder.toString(); } private static void dropAllTables(Database db, boolean ifExists, @NonNull Class<? extends AbstractDao<?, ?>>... daoClasses) { reflectMethod(db, "dropTable", ifExists, daoClasses); printLog("【Drop all table】"); } private static void createAllTables(Database db, boolean ifNotExists, @NonNull Class<? extends AbstractDao<?, ?>>... daoClasses) { reflectMethod(db, "createTable", ifNotExists, daoClasses); printLog("【Create all table】"); } /** * dao class already define the sql exec method, so just invoke it */ private static void reflectMethod(Database db, String methodName, boolean isExists, @NonNull Class<? extends AbstractDao<?, ?>>... daoClasses) { if (daoClasses.length < 1) { return; } try { for (Class cls : daoClasses) { Method method = cls.getDeclaredMethod(methodName, Database.class, boolean.class); method.invoke(null, db, isExists); } } catch (NoSuchMethodException e) { e.printStackTrace(); } catch (InvocationTargetException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } } private static void restoreData(Database db, Class<? extends AbstractDao<?, ?>>... daoClasses) { for (int i = 0; i < daoClasses.length; i++) { DaoConfig daoConfig = new DaoConfig(db, daoClasses[i]); String tableName = daoConfig.tablename; String tempTableName = daoConfig.tablename.concat("_TEMP"); if (!isTableExists(db, true, tempTableName)) { continue; } try { // get all columns from tempTable, take careful to use the columns list List columns = getColumns(db, tempTableName); ArrayList properties = new ArrayList<>(columns.size()); for (int j = 0; j < daoConfig.properties.length; j++) { String columnName = daoConfig.properties[j].columnName; if (columns.contains(columnName)) { properties.add(columnName); } } if (properties.size() > 0) { final String columnSQL = TextUtils.join(",", properties); StringBuilder insertTableStringBuilder = new StringBuilder(); insertTableStringBuilder.append("INSERT INTO ").append(tableName).append(" ("); insertTableStringBuilder.append(columnSQL); insertTableStringBuilder.append(") SELECT "); insertTableStringBuilder.append(columnSQL); insertTableStringBuilder.append(" FROM ").append(tempTableName).append(";"); db.execSQL(insertTableStringBuilder.toString()); printLog("【Restore data】 to " + tableName); } StringBuilder dropTableStringBuilder = new StringBuilder(); dropTableStringBuilder.append("DROP TABLE ").append(tempTableName); db.execSQL(dropTableStringBuilder.toString()); printLog("【Drop temp table】" + tempTableName); } catch (SQLException e) { Log.e(TAG, "【Failed to restore data from temp table 】" + tempTableName, e); } } } private static List getColumns(Database db, String tableName) { List columns = null; Cursor cursor = null; try { cursor = db.rawQuery("SELECT * FROM " + tableName + " limit 0", null); if (null != cursor && cursor.getColumnCount() > 0) { columns = Arrays.asList(cursor.getColumnNames()); } } catch (Exception e) { e.printStackTrace(); } finally { if (cursor != null) cursor.close(); if (null == columns) columns = new ArrayList<>(); } return columns; } private static void printLog(String info){ if(DEBUG){ Log.d(TAG, info); } }} /** * FileName: MSQLiteOpenHelper * Author: bai * Date: 2019/4/12 14:19 * TODO 自定义 MySQLiteOpenHelper集成 DaoMaster.OpenHelper 重写更新数据库的方法 * 当app下的build.gradle 的schemaVersion数据库的版本号改变时，，创建数据库会调用onUpgrade更细数据库的方法 */public class MSQLiteOpenHelper extends DaoMaster.OpenHelper{ /** * * @param context 上下文 * @param name 原来定义的数据库的名字 新旧数据库一致 * @param factory 可以null */ public MSQLiteOpenHelper(Context context, String name, SQLiteDatabase.CursorFactory factory) { super(context, name, factory); } /** * * @param db Database * @param oldVersion int * @param newVersion int * 更新数据库的时候它自己会调用 */ @Override public void onUpgrade(Database db, int oldVersion, int newVersion) { Log.d("flag","-----调用了"); //具体的数据转移在MigrationHelper2类中 /** * 将db传入 将gen目录下的所有的Dao.类传入 */ MigrationHelper2.migrate(db,LoginBeanDao.class); }}
MainActivity.java调用greenDao增删改查的使用：/** * https://github.com/yuweiguocn/GreenDaoUpgradeHelper 升级数据库官网源码 * https://blog.csdn.net/xuwb123xuwb/article/details/73509107 升级参考 */class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val loginBean = LoginBean() loginBean.userName = "漠天" loginBean.password = "111111" loginBean.telPhone = "8888888888888888" val loginDao = LoginDao(this) loginDao.insertLoginBean(loginBean) val loginResultBean = loginDao.queryLoginList() Log.d("login",loginResultBean[0].userName) }}
demo源码：https://download.csdn.net/download/u010326875/11109916
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