On 01/08/2014 05:51 AM, Tadeas Kriz wrote:
Hey everyone,
I’ve been recently going through the DataManager API in
aerogear-android. In this email, I’d like to suggest
addiction of two method (or possibly three) into the
`Store<T>` interface. These would be:
```java
/**
* If store is open, it can be read or written to.
*/
boolean isOpen();
/**
* Opens store in current thread (blocking).
*/
Store<T> open();
/**
* Opens store in background thread and then
callback#onSuccess is called.
*/
void open(Callback<Store<T>> callback);
```
I think those are fine. Feel free to JIRA it up and Passos
and I will
review.
From my point of view, this makes
sense to be in the `Store<T>` so I can switch
between stores easily during development with no need to
change other code. Also, if `read` or `write` operations
are done with closed store, there are two possible
workflows. First one is, that I’d fail and throw an
exception. Second (and for me a preferred one) is, that
all those methods would internally check if the store is
open and if not, they’d call the `open` method. This
also leads me to another API change for
`Store<T>`.
```java
/**
* Reads all the data from the underlying storage system
asynchronously.
*/
void readAll(Callback<Collection<T>>
callback);
/**
* Reads a specific object/record from the underlying
storage system asynchronously.
*/
void read(Serializable id, Callback<T> callback);
/**
* Search for objects/records from the underlying storage
system asynchronously.
*/
void readWithFilter(ReadFilter filter,
Callback<List<T>> callback);
/**
* Saves the given object in the underlying storage system
asynchronously.
*/
void save(T item, Callback<Void> callback);
/**
* Resets the entire storage system asynchronously.
*/
void reset(Callback<Void> callback);
/**
* Removes a specific object/record from the underlying
storage system asynchronously.
*/
void remove(Serializable id, Callback<Void>
callback);
/**
* Checks if the storage system contains no stored
elements asynchronously.
*/
void isEmpty(Callback<Boolean> callback);
```
That’s right, async methods for easy access to the storage
from background thread, without the pain of writing it
myself (for example, it makes no sense if I want to just
call `store.save(..)` and I’d have to write all the
`AsyncTask` boilerplate).
So, what do you think?
I would rather throw an exception than open a database when
you call
read and friends. That way a developer doesn't accidentally
open a
database he meant to be closed. I don't have that strong of
a feeling on
that point one way or another however.