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The Java Developers Almanac 1.4 |
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e414. Removing a Preference NodeRemoving a preference node will remove all of the node's descendants.See also e415 Determining If a Preference Node Exists. 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) {
}
e412. Creating a Preference Node e413. Retrieving a Preference Node e415. Determining If a Preference Node Exists e416. Retrieving the Parent and Child Nodes of a Preference Node e417. Finding a Preference in a Preference Tree
© 2002 Addison-Wesley. |