From 6da6d38074f8df37160bce46bebd86dd67c65646 Mon Sep 17 00:00:00 2001 From: pjepscklu <167234571@qq.com> Date: Tue, 7 Apr 2026 11:59:08 +0800 Subject: [PATCH] Delete 'DBHelper.java' --- DBHelper.java | 111 -------------------------------------------------- 1 file changed, 111 deletions(-) delete mode 100644 DBHelper.java diff --git a/DBHelper.java b/DBHelper.java deleted file mode 100644 index 1c9fef1..0000000 --- a/DBHelper.java +++ /dev/null @@ -1,111 +0,0 @@ -package com.example.sparrownotes.util; - -import android.content.Context; -import android.database.sqlite.SQLiteDatabase; -import android.util.ArrayMap; - -import com.example.sparrownotes.bean.NoteBean; -import com.example.sparrownotes.bean.UserBean; -import com.example.sparrownotes.util.Constant; -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; - -import java.sql.SQLException; - -/** - * 数据库帮助类 - * - * @author Horsen - */ -@SuppressWarnings("AlibabaRemoveCommentedCode") -public class DBHelper extends OrmLiteSqliteOpenHelper { - /** - * 防止多线程同时操作, 实现单例模式, 并锁定线程 - * 数组存储App中所有的Dao对象的Map集合 - */ - private static DBHelper dbHelper = null; - private ArrayMap daos = new ArrayMap<>(); - - public static synchronized DBHelper getInstance(Context context) { - if (dbHelper == null) { - synchronized (DBHelper.class) { - if (dbHelper == null) { - dbHelper = new DBHelper(context); - } - } - } - return dbHelper; - } - - private DBHelper(Context context) { - super(context, Constant.DB_NAME, null, Constant.DB_VERSION); - } - - /** - * 包含创建表的语句 - * - * @param sqLiteDatabase - * @param connectionSource - */ - @Override - public void onCreate(SQLiteDatabase sqLiteDatabase, ConnectionSource connectionSource) { - try { - TableUtils.createTable(connectionSource, UserBean.class); - TableUtils.createTable(connectionSource, NoteBean.class); - } catch (SQLException e) { - e.printStackTrace(); - } - - } - - /** - * 包含新建表的语句 - * 就是删了再创罢了 - * - * @param sqLiteDatabase - * @param connectionSource - * @param i - * @param i1 - */ - @Override - public void onUpgrade(SQLiteDatabase sqLiteDatabase, ConnectionSource connectionSource, int i, int i1) { - try { - TableUtils.dropTable(connectionSource, UserBean.class, false); - TableUtils.dropTable(connectionSource, NoteBean.class, false); - onCreate(sqLiteDatabase, connectionSource); - } catch (SQLException e) { - e.printStackTrace(); - } - } - - /** - * 根据传入的Dao路径获取这个Dao的单例对象, 要么从daos中获取, 要么新建一个存入daos - */ - @Override - public synchronized Dao getDao(Class clazz) throws SQLException { - Dao dao = null; - String className = clazz.getSimpleName(); - if (daos.containsKey(className)) { - dao = daos.get(className); - } - if (dao == null) { - dao = super.getDao(clazz); - daos.put(className, dao); - } - return dao; - } - - /** - * 释放资源 - */ - @Override - public void close() { - super.close(); - for (String key : daos.keySet()) { - Dao dao = daos.get(key); - dao = null; - } - } -}