Interacting with the persistent storage

The Storage Runtime Interface (SRI) provides some functions to interact with the storage backend. All of them are aimed at enabling the COMPSs runtime to deal with persistent data across the infrastructure.

However, the function to retrieve an object from the storage backend from its identifier can be useful for the user. Consequently, users can import the SRI and use the getByID function when needed necessary. This function requires a String parameter with the object identifier, and returns the object associated with that identifier (null or None otherwise).

The following subsections detail how to call the getByID function in Java and Python applications.

Java

Import the getByID function from the storage api and use it:

import storage.StorageItf;
import MyPackage.MyClass;

class Test{
    // ...
    public static void main(String args[]){
        // ...
        obj = StorageItf.getByID("my_obj");
        // ...
    }
}

Python

Import the getByID function from the storage api and use it:

from storage.api import getByID

..
obj = getByID('my_obj')
...

C/C++

Unsupported

Persistent storage is not supported with C/C++ COMPSs applications.