极速开发框架dhroid之sqlite优化_sqlite 极速-优快云博客

小弟在从dhroid框架中抽出qlite的最轻量orm框架
1、将sqlite的最轻量orm框架优化
2、添加方法同步锁
[mw_shl_code=java,true]       private Lock writeLock = new ReentrantLock();
      private volatile boolean writeLocked = false;
      private void lock() {
            writeLock.lock();
            writeLocked = true;
      }

      private void unlock() {
            if (writeLocked) {
                     writeLock.unlock();
                     writeLocked = false;
            }
      }

      /**
      * 保存
      * @param obj
      */
      public void save(Object obj) {
            if (obj == null)
                     return;
            try{
                     lock();
                     checkOrCreateTable(obj.getClass());
                     SqlProxy proxy = SqlProxy.save(obj);
                     db.execSQL(proxy.getSql(), proxy.paramsArgs());
            }finally{
                     unlock();
            }
      }[/mw_shl_code]
3、添加数据库表字段动态增删改
[mw_shl_code=java,true]       /**
      * 检查表
      * @param clazz
      */
      private void checkOrCreateTable(Class<?> clazz) {
            EntityInfo entity = EntityInfo.build(clazz);
            if (entity.isChecked())
                     return;

            Cursor cursor = db.rawQuery("SELECT name FROM sqlite_master WHERE type='table' and name='"+entity.getTable()+"' order by name",null);
            Integer count = cursor != null ? cursor.getCount() : null;
            if(cursor != null)
                     cursor.close();
            if(count != null && count > 0){
                     String [] columnNames = getColumnNames(db, entity.getTable());
                     if(columnNames != null && columnNames.length > 0){
                              if(changeTable(clazz, columnNames)){
                                    String columns = "";
                                    boolean first = true;
                                    List<ColumnInfo> list = entity.getColumnList();
                                    for(int i=0,length=columnNames.length;i<length;i++){
                                             for(ColumnInfo mColumnInfo : list){
                                                      if(mColumnInfo.getColumName().equals(columnNames )){
                                                            columns += (first ? "" : ",")+columnNames;
                                                            first = false;
                                                      }
                                             }
                                    }

                                    if(TextUtils.isEmpty(columns)){
                                             //删除
                                             db.execSQL("DROP TABLE " + entity.getTable());
                                             //创建表
                                             String sql = getCreatTableSQL(clazz);
                                             db.execSQL(sql);
                                    }else{
                                             String tempTableName = entity.getTable() + "_temp";
                                             //表重命名
                                             db.execSQL("ALTER TABLE " + entity.getTable() + " RENAME TO " + tempTableName);
                                             //创建表
                                             String sql = getCreatTableSQL(clazz);
                                             db.execSQL(sql);
                                             //旧数据转移
                                             db.execSQL("INSERT INTO "+entity.getTable()+"("+columns+") SELECT "+columns+" FROM "+tempTableName);
                                             //删除临时表
                                             db.execSQL("DROP TABLE "+tempTableName);
                                    }
                              }
                     }else{
                              //删除
                              db.execSQL("DROP TABLE " + entity.getTable());
                              //创建表
                              String sql = getCreatTableSQL(clazz);
                              db.execSQL(sql);
                     }
            }else{
                     //创建表
                     String sql = getCreatTableSQL(clazz);
                     db.execSQL(sql);
            }
            entity.setChecked(true);
      }[/mw_shl_code]4、本框架没有链表查询功能，int、Integer、long、Long、float、Float、double、Double、Boolean、String、Date以外字段利用GSON中的 Gson .toJson( Object src, Type typeOfSrc)获得json数据插入数据库，读取使用 Gson .fromJson( String json, Type typeOfT)获得相应对象，具体看DEMO
[mw_shl_code=java,true] /**
   * 获取属性
   * @param o
   * @param info
   * @return
   */
public static Object getProperty(Object o,ColumnInfo info){
try {
if(info.isBean()){
Field f = info.getField();
f.setAccessible(true);
Object value = f.get(o);
Gson gson = new GsonBuilder().create();
return gson.toJson(value,f.getGenericType());
}else{
Field f = info.getField();
f.setAccessible(true);
return f.get(o);
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}[/mw_shl_code]

[mw_shl_code=java,true] /**
   * 添加屬性
   * @param o
   * @param info
   * @param value
   */
public static void setProperty(Object o,ColumnInfo info,Object value){
try {
if(info.isBean()){
Field f = info.getField();
Gson gson = new GsonBuilder().create();
Object obj = gson.fromJson((String) value, f.getGenericType());
f.setAccessible(true);
f.set(o, obj);
}else{
Field f = info.getField();
f.setAccessible(true);
f.set(o, value);
}
} catch (Exception e) {
e.printStackTrace();
}
}[/mw_shl_code]