Realm 未在反射时为对象的字段设置值（Android）

Question

我正在尝试实现对领域的抽象，以便在对数据库使用 CURD 操作时可以节省一些时间。

我构建的抽象是controller数据库操作，以便我可以使用controller它对任何表执行 CURD 操作。

即controller我所说的只是一个 Javaclass有四种方法 create update read delete。

这是create使用反射来创建db objects和绑定传递data object给那个的字段db object

 /**
     * this method will delete the old data "you can change that"
     * of the table then store the passed data array in the table
     *
     * @param datum    the data Object you want to
     *                 save in the database
     * @param map      this map will contain which field
     *                 value in the data class will be
     *                 binded to which field in the db class
     *                 and will have this form dataFieldName => dbFieldName
     * @param callback when the function finish it's work it will
     *                 return a boolean value indicate whether
     *                 the function successfully finish it's work
     */
    public void create(
            Object datum,
            Class dataClass,
            HashMap<String, String> map,
            SaveDataCallback callback
    ) {
        Realm realm = Realm.getInstance(configuration);
        realm.executeTransactionAsync(bgRealm -> {
                    long id;

                    Number currentId = bgRealm.where(clacc).max("id");//the clacc object is passed in the constructor of the controller  
                    if (currentId == null)
                        id = 1;
                    else
                        id = currentId.longValue() + 1;

                    RealmObject dbObject = bgRealm.createObject(clacc, id++);//the clacc object is passed in the constructor of the controller 
                    mapObjects(datum, dataClass, dbObject, clacc, map);



                }
                , () -> callback.onSavingDataFinished(true)
                , error -> callback.onSavingDataFinished(false));
    }


private void mapObjects(
            Object source,
            Class sourceClass,
            Object destination,
            Class destinationClass,
            HashMap<String, String> map) {
        String[] sourceFieldNames = map.keySet().toArray(new String[map.size()]);

        try {

            for (int i = 0; i < map.size(); i++) {
                Field sourceField = sourceClass.getDeclaredField(sourceFieldNames[i]);
                sourceField.setAccessible(true);
                Object sourceValue = sourceField.get(source);

                String destinationFieldName = map.get(sourceFieldNames[i]);
                Field destinationField = destinationClass.getDeclaredField(destinationFieldName);
                destinationField.setAccessible(true);

                if (sourceField.getType() == Short.TYPE) {
                    destinationField.set(destination, Short.parseShort(sourceValue.toString()));
                    continue;
                }
                if (sourceField.getType() == Integer.TYPE) {
                    destinationField.set(destination, Integer.parseInt(sourceValue.toString()));
                    continue;
                }
                if (sourceField.getType() == Long.TYPE) {
                    destinationField.set(destination, Long.parseLong(sourceValue.toString()));
                    continue;
                }
                if (sourceField.getType() == Float.TYPE) {
                    destinationField.set(destination, Float.parseFloat(sourceValue.toString()));
                    continue;
                }
                if (sourceField.getType() == Double.TYPE) {
                    destinationField.set(destination, Double.parseDouble(sourceValue.toString()));
                    continue;
                }
                if (sourceField.getType() == Byte.TYPE) {
                    destinationField.set(destination, Byte.parseByte(sourceValue.toString()));
                    continue;
                }
                if (sourceField.getType() == Boolean.TYPE) {
                    destinationField.set(destination, Boolean.parseBoolean(sourceValue.toString()));
                    continue;
                }
                destinationField.set(destination, sourceValue);

            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

问题如下：

当我尝试在进程完成后查询数据库以获取对象时，数据库返回我使用此函数创建的对象，但这些对象没有数据 actually the returned data is set to default value to each type i.e. string to null boolean to false etc...

我的问题是：

我的代码中是否有任何问题，或者领域数据库不支持在反射时为对象设置值？

Answer 1

Realm 不支持通过反射设置托管对象的字段值。

但是，如果您通过反射调用 setter 方法，它将起作用。