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POSerializing is not storing object data, only object references
 

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    <p>I have a node tree built out of Node objects. They are more complex than the code I am showing but only have primitive or Serializable instance members.</p> <p>Assuming each Node can have up to 10 children the code looks a bit like so.</p> <pre><code>public class Node implements Serializable{ private static final long serialVersionUID = -848926218090221003L; private Node _parent; private boolean _hasParent; private Node[] _children; private int _childCount = 0; public Node(Node parent){ _children = new Node[10]; _parent = parent; _hasParent = (parent != null); } ... //Various accessors etc } </code></pre> <p>Now this tree is quite expensive to build but once it is done I write it to a file:</p> <pre><code>ObjectOutputStream serializedOuput = new ObjectOutputStream(new FileOutputStream(cacheFile)); serializedOuput.writeObject(tree); serializedOuput.close(); </code></pre> <p>When I am done caching the tree I make some irreversable changes to like trimming off unneeded branches.</p> <p>Then when I next need a base tree to work from I create a new tree object by reading in my serialized file.</p> <p>The problem...</p> <p>Creating the tree from the file seems to simply create a new object that points to the old one. In other words the modifications made after writing to file have also been made to the new tree.</p> <p>If I restart the app and try reading in the serialized file it returns null.</p> <p>So I seem to be serializing object references rather than the object itself, any ideas where I am going wrong?</p>
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    1. USAdrian Hope-Bailie
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