[hibbert]

hi,
i have a vector. each item of this vector is an object of an own class (always the same calss).

now i want to save this vector and reaload it the next time my application is started.

is teher a way to do this?

thanks hibbert

[hrbuckley]

Check out the PersistentStore, and the Persistable interface.

[hibbert]

hi, ok i have written my own class, which should save a vector.
i run my application -> load non existing data -> nothing happens -> OK
i gererate some data to save it > save the data -> OK -> quit the application
i run my application again -> load existing data -> data is shown -> OK
i turn of my blackberry (remove the batterie) -> boot it -> run my application -> load da... what? where is my data? the vector is null. what's wrong?

here is my complete class:

PHP Code:

class clsSave {
    private static Vector _data;
    private static PersistentObject store; // = PersistentStore.getPersistentObject(0x444ed4bfea1c3f22L);
    
    clsSave() { // constructor
        if (store == null) store = PersistentStore.getPersistentObject(0x444ed4bfea1c3f22L);
        _data = new Vector();
    }
    
    public void save(Vector _liste) { // gets a vaector, and should save it
        if (store == null) store = PersistentStore.getPersistentObject(0x444ed4bfea1c3f22L);
        synchronized(store) {
            store.setContents(_liste);
            store.commit();
        }
    }
    public Vector load() { // get the persistent data and returns a vector
        synchronized(store) {
            _data = (Vector)store.getContents();
        }
        return _data;
    }
} 


so why is teh data los when i turn off my BB?

thanks hibbert

[simon.hain]

seems strange. did you try to actually put something into the vector? just a guess, maybe the system GCs the store because there is only an empty vector in it.

[hibbert]

hi,
as i wrote in my last post, i store some data into the vector, quit my programm and restart it. then the data is loaded correctly. even if i shutdown the BB then the data is lost.

any ideas?

thanks hibbert

[blakeburry]

I do the same thing. As long as the battery stays charged in the device the data are there. If you remove the battery and insert it again the data is lost.

I'm looking for a solution for quite a while.

At the moment I have additional problems with commit() - it crashes most of the time but the reason for this is probably my own fault.

[hibbert]

hi,
if i store a string array with a fixed size then the data is saved correctly, also if i remove the batterie.
maybe the problem is, that a vector can have different sizes. maybe i just have to say: dear BB, give me space for 15 elements, also when my vector has just 4 elements.

is there a way to try it this way? ^^

thanks hibbert

[Ivanov]

try the "static way"

class clsSave {
    private static Vector _data;
    private static PersistentObject store;

    static
    {
        store= PersistentStore.getPersistentObject(0x444ed4bfea1c3f22L);
        synchronized (store)
        {
            _data= (Vector) store.getContents();
            if (_data== null)
            {
                _data= new Vector();
                store.setContents(_data);
                store.commit();
            }
        }
    }

    
    clsSave() { // constructor
    }
    
    public void save(Vector _liste) {
        _data = _liste;
        synchronized (store)
        {
            store.setContents(_data);
            store.forceCommit();
        }
    }
    public Vector load() {
        return _data;
    }
}

This should work however it might be not necessary to replace the Vector object in the store by a new one. In my application I define getter and setter for the vector's element not for the vector itself.

[hibbert]

hi,
it is of no importance how i access to the vector,or? the main problem is to save it permanently.

your way returns the same result as my one.
i can restart the application an the data is loaded. but if i remove the battery then teh data is lost :(

hibbert

[Ivanov]

try to copy all elements of _liste into _data beacuse
_data = _liste

sets only the reference to the new vector without making a deep copy

so try that:

    public void save(Vector _liste) {
        _data.removeAllElements();
        for (Enumeration e = _liste.elements(); e.hasMoreElements();)
        {
              _data.addElement(e.nextElement());
        }
        synchronized (store)
        {
            store.forceCommit();
        }
    }

[hibbert]

at the moment i have try it with this one here:

PHP Code:

public void save(Vector _liste) {
        try {
            if (_data == null) _data = new Vector();
            this._data.removeAllElements();
            for (Enumeration e = _liste.elements(); e.hasMoreElements();){
                _data.addElement(e.nextElement());
            }
    
            if (store == null) store = PersistentStore.getPersistentObject(0x444ec4babc0c3f52L); 
            synchronized (store){
                store.setContents(_data);
                store.commit();
            }
        } catch (Exception ex) {System.out.println("error 0x5540: "+ex.toString());}
    } 


and i get this error:
error 0x5540: net.rim.device.api.system.NonPersistableObjectExce ption
but i don't have any idea. store and _data are not null.

hibbert

[Ivanov]

a question in between:
what do you save in your _data vector?

if it's your own class it has to implement the Persistable interface as well.

[hibbert]

hi,
each item of my _data vector is one of my own class (see first post).

how doi implement the persistable interface to my own class?

hibbert

[Ivanov]

import net.rim.device.api.util.Persistable;

class MyPersistableClass implements Persistable
{
}

[hibbert]

Originally Posted by Ivanov

import net.rim.device.api.util.Persistable;

class MyPersistableClass implements Persistable
{
}

jepp, i found it my self, was reallay an easy step ^^

i have tried this one, and i don't know what i should say....

it works

thanks alot for your help

[blakeburry]

Ahhh! This is the solution. If it is implemented right there are no crashes and the data is saved. Real nice from the compiler that it doesn't even warn you if you forgot the implementation...

Thanks a lot.

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