org.researchstack.backbone.storage.file

Interface FileAccess

All Known Implementing Classes:

SimpleFileAccess

public interface FileAccess

Generic file access contract for the app. Depending on the type, there may need to be auth input screens shown to the user. Also, its possible to implement completely cloud based storage, so the developer will need to be aware of the detail implementations to some degree.

Because some storage will need to show auth info to the user before interaction can start, the normal Android lifecycle of Fractivities will need to be modified a bit. In general, code will hit 'onCreate', which will check for live file access, and if there's an issue, show a different UI to the user to resolve. A new part of the lifecycle, onDataReady (or similar) will need to be added. This intended to be run whenever auth is complete, but may happen outside of the standard onCreate/onResume callbacks.

Its assumed that in most cases, once the app has authed, file access should be readily available. If that is NOT the case, for example if a google auth expires, the developer will have to implement an exception case flow. If rare, simply letting the app crash and auth on a restart might be sufficient, but planning for crashes isn't the most elegant of solutions ;)

This is highly volatile at the moment. The interface may change dramatically.

Created by kgalligan on 11/24/15.

Method Summary

Modifier and Type	Method and Description
void	clearData(android.content.Context context, java.lang.String path)
boolean	dataExists(android.content.Context context, java.lang.String path) See if we have the data.
void	moveData(android.content.Context context, java.lang.String fromPath, java.lang.String toPath)
byte[]	readData(android.content.Context context, java.lang.String path) Read data.
void	setEncrypter(Encrypter encrypter) Set the encrypter.
void	writeData(android.content.Context context, java.lang.String path, byte[] data) Save data.

Method Detail

writeData

void writeData(android.content.Context context,
               java.lang.String path,
               byte[] data)

Save data. Do not call this before you init or you'll get an exception. Also, networked storage has the high probability of network based exceptions. Use extra caution in those situations.

Parameters:

context - Can be Application context, but we'll be careful not to store, so don't worry too much.

path - Path relative to the implementation's root store. Must start with '/'. No relative paths.

data - Byte array. May implement streams in the future if all implementations support it.

readData

byte[] readData(android.content.Context context,
                java.lang.String path)

Read data. Do not call this before you init or you'll get an exception. Also, networked storage has the high probability of network based exceptions. Use extra caution in those situations. If the path does not exist, you'll get an exception, not a null. Just FYI. That may change.

Parameters:

context - Can be Application context, but we'll be careful not to store, so don't worry too much.

path - Path relative to the implementation's root store. Must start with '/'. No relative paths.

moveData

void moveData(android.content.Context context,
              java.lang.String fromPath,
              java.lang.String toPath)

Parameters:

context -

fromPath -

toPath -

dataExists

boolean dataExists(android.content.Context context,
                   java.lang.String path)

See if we have the data.

Parameters:

context - Can be Application context, but we'll be careful not to store, so don't worry too much.

path - Path relative to the implementation's root store. Must start with '/'. No relative paths.

Returns:

Well...

clearData

void clearData(android.content.Context context,
               java.lang.String path)

setEncrypter

void setEncrypter(Encrypter encrypter)

Set the encrypter. All data is passed through this object to be encrypted before save/decrypted after loading. For no encryption, use an encrypter that passes the data back unchanged.

Parameters:

encrypter - Encrypter.