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<TITLE>Removing a Preference Node (Java Developers Almanac Example)
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  <h3>e414. Removing a Preference Node</h3>

Removing a preference node will remove all of the node's
descendants.

<P>
See also <a href="../java.util.prefs/NodeExists.html" class="eglink"><b>e415</b> Determining If a Preference Node Exists</a>.


<pre>    try {
        // First check to see if the node is already removed;
        // otherwise, getting the node will automatically create it
        boolean exists = Preferences.userRoot().nodeExists("/foo"); // false
    
        if (!exists) {
            // Get the node
            Preferences prefs = Preferences.userRoot().node("/foo");
    
            // Remove the node
            prefs.removeNode();
    
            // Trying to remove it again would cause an IllegalStateException
            //prefs.removeNode();
        }
    
        // Create a node with a child
        Preferences prefs = Preferences.userRoot().node("/foo/child");
        exists = Preferences.userRoot().nodeExists("/foo");       // true
        exists = Preferences.userRoot().nodeExists("/foo/child"); // true
    
        // Remove the parent node
        Preferences.userRoot().node("/foo").removeNode();
    
        // Both parent and child are removed
        exists = Preferences.userRoot().nodeExists("/foo");       // false
        exists = Preferences.userRoot().nodeExists("/foo/child"); // false
    } catch (BackingStoreException e) {
    }
</pre>
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            &nbsp;<b>Related Examples</b></font></td>
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e411. <a class="eglink" href="GetRoot.html?l=rel">
    Getting the Roots of the Preference Trees
</a>
<br>

e412. <a class="eglink" href="CreateNode.html?l=rel">
    Creating a Preference Node
</a>
<br>

e413. <a class="eglink" href="GetNode.html?l=rel">
    Retrieving a Preference Node
</a>
<br>

e415. <a class="eglink" href="NodeExists.html?l=rel">
    Determining If a Preference Node Exists
</a>
<br>

e416. <a class="eglink" href="GetRelative.html?l=rel">
    Retrieving the Parent and Child Nodes of a Preference Node
</a>
<br>

e417. <a class="eglink" href="FindPref.html?l=rel">
    Finding a Preference in a Preference Tree
</a>
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        See also: 
<a class="eglink" href="/egs/java.util.prefs/pkg.html?l=rel#Events">
    Events
</a>&nbsp;&nbsp;

<a class="eglink" href="/egs/java.util.prefs/pkg.html?l=rel#Importing%20and%20Exporting">
    Importing and Exporting
</a>&nbsp;&nbsp;

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