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saving (serializing) a complete tree structure of a JTree

Hello Experts,

how can I serialize (save to a file) a complete tree structure of a Jtree ?

I used DefaultMutableTreeNodes.

The complete Tree has about 8000 nodes.

First I read the node informations from a text file, but this takes about 10 minutes, which is too long.

So I am looking for a possibility to save the complete JTree object or the nodes.

Best regards

F

chrisos

JTree implements the Serialisable interface so you should be able to do the following:

File outFile = new File("wherever");
FileOutputStream fos = new FileOutputStream(outFile);
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(myJTree);

To load the tree back in you do:

File inFile = new File("wherever");
FileInputStream fis = new FileInputStream(inFile);
ObjectInputStream ois = new ObjectInputStream(fis);
myJTree = (JTree)oos.readObject();

Hope that helps,

Chrisos

kylar

Ooo, Bad idea. You should never serialize Swing Objects, b/c they are not compatible with future versions. you should serialize the Tree Model instead.

Cheers,
Kylar

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Igor Bazarny

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jimsims

the reason it is so slow is because each element likely has a reference to the tree, which causes a save of the whole tree for each element.

You should override the deafult serializer and walk the tree yourself, saving each node individually.

I had this same problem a few years back and eventually found this solution - went from 5 minutes to serialze a queue to 10 seconds, by serialing the queue myself and then serializing the ind objects

sajuks

@bazarny..thanx a lot Sir..you really are a master:-)