开源一个轻量级无侵入式android数据库自动升级的管理类

　　SpeSqliteManager4Android
　　介绍
　　一个轻量级无侵入式管理android数据库自动升级的管理类(支持SQLiteOpenHelper、room(编码中))
　　实际导入代码
　　核心代码 1. 数据库配置文件dbupdate.json {   ＂dbName＂: ＂localdb＂,   ＂dbVersion＂: 5 ,   ＂dbTables＂: [     {       ＂tableName＂:＂dbconfig＂,       ＂columns＂:[         {           ＂key＂: ＂dbversion＂,           ＂keyType＂: ＂TEXT＂         },         {           ＂key＂: ＂dbname＂,           ＂keyType＂: ＂TEXT＂         },         {           ＂key＂: ＂dbtables＂,           ＂keyType＂: ＂TEXT＂         }       ]     },     {       ＂tableName＂:＂teacher＂,       ＂columns＂:[         {           ＂key＂: ＂id＂,           ＂keyType＂: ＂INTEGER PRIMARY KEY AUTOINCREMENT＂         },         {           ＂key＂: ＂name＂,           ＂keyType＂: ＂TEXT＂         },         {           ＂key＂: ＂age＂,           ＂keyType＂: ＂TEXT＂         },         {           ＂key＂: ＂sex＂,           ＂keyType＂: ＂TEXT＂         }       ]     }   ] }  2.开始调用 SpeSqliteDBService.getInstance(this);  3.数据库相关模型 public class SpeSqliteColumnSettingModel {     /**      * key名      */     public String key;      /**      * 该key的在sql中的key字段修饰,比如INTEGER PRIMARY KEY AUTOINCREMENT或TEXT      */     public String keyType; }  public class SpeSqliteSettingModel {     /**      * 数据库名      */     public String dbName;      /**      * 数据库版本号      */     public int dbVersion;      /**      * 所有表数组      */     public ArrayList dbTables; }  public class SpeSqliteTableSettingModel {     /**      * 表名      */     public String tableName;      /**      * 当前表字段设计      */     public ArrayList columns;      /**      * 是否被索引过：代表是否在新表里被删除了      */     public  boolean indexed;  }  4.SQLiteOpenHelper子类,可以看到改完后该类非常干净。 public class SpeSqliteDBService extends SQLiteOpenHelper {     private static final String TAG     = ＂SpeSqliteDBService＂;     private static SpeSqliteDBService instance  = null;     private Context context = null;     private SQLiteDatabase db = null;     public static synchronized SpeSqliteDBService getInstance(Context context) {         if (instance == null){             synchronized (SpeSqliteDBService.class){                 if (instance == null){                     instance = new SpeSqliteDBService(context);                     instance.context = context;                     instance.db = instance.getWritableDatabase();                 }             }         }         return instance;     }      public SpeSqliteDBService(Context context) {         super(context,SpeSqliteUpdateManager.getInstance().init(context).currentAppDBSetting().dbName,                 null,SpeSqliteUpdateManager.getInstance().init(context).currentAppDBSetting().dbVersion);     }      @Override     public void onCreate(SQLiteDatabase db) {         SpeSqliteUpdateManager.getInstance().create(db);     }      @Override     public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion) {          SpeSqliteUpdateManager.getInstance().upgrade(db);     } }  5.SpeSqliteUpdateManager 负责针对本地db的创建、新建表、表字段升级、删除表,通过配置的方式去升级数据库，减少代码的改动，核心思想：以静制动  public class SpeSqliteUpdateManager {     /**      *主app的context      */     private Context appContext = null;      /**      *本地db中的配置项      */     private SpeSqliteSettingModel localDBSetting = null;      /**      *当前app中assets的配置项      */     private SpeSqliteSettingModel currentAppDBSetting = null;      private final  Gson gson = new Gson();      private String currentDBJson = null;      private static final String kDBJsonName  = ＂dbupdate.json＂;      private SpeSqliteUpdateManager() {      }      public static SpeSqliteUpdateManager getInstance() {         return SingletonClassInstance.instance;     }      private static class SingletonClassInstance {         private static final SpeSqliteUpdateManager instance = new SpeSqliteUpdateManager();     }      public SpeSqliteUpdateManager init(Context context){         this.appContext =context;         return this;     }      /**      * 数据库第一次创建时的调用函数      * @param db db      */     public void create(SQLiteDatabase db){         SpeSqliteSettingModel currentDBModel = SpeSqliteUpdateManager.getInstance().currentAppDBSetting();         for(int i=0;i=_old.columns.size()){                 SpeSqliteColumnSettingModel column = _new.columns.get(i);                 String sql = ＂ alter table ＂+_old.tableName+＂ add column ＂;                 sql+=column.key;                 sql+=＂ ＂;                 sql+= column.keyType;                 executeSQL(db,sql);             }         }     }      /**      * 新增表      * @param db db      * @param table 表配置      */     private void createTableSQL(SQLiteDatabase db,SpeSqliteTableSettingModel table){         String sql = ＂ create table if not exists ＂+table.tableName+＂ (＂;         for(int j=0;j();             for(int i=0;i