The issue [1] does not seem like a bug to me as the behavior appears to be as expected from the specification but I would like to see whether anyone else agrees.
Assuming the nodes “userRoot/a” and “userRoot/a/a1” do not already exist, if the test [2] is run twice in succession, the printed output of the first run is "a" exists: false "a1" exists: false and that of the second run is "a" exists: true "a1" exists: false This appears to be consistent with this statement in the class level specification of j.u.Preferences [3]: "Normal termination of the Java Virtual Machine will not result in the loss of pending updates -- an explicit flush invocation is not required upon termination to ensure that pending updates are made persistent.” I verified that the behavior is consistent with this across Linux, OS X, and Windows. Any comment would be appreciated. Thanks, Brian [1] https://bugs.openjdk.java.net/browse/JDK-8151955 [2] RemoveNodeTest.java import java.util.prefs.BackingStoreException; import java.util.prefs.Preferences; public class RemoveNodeTest { public static void main(String[] args) throws BackingStoreException { Preferences userRoot = Preferences.userRoot(); System.out.printf("\"a\" exists: %s%n", userRoot.nodeExists("a")); Preferences a = userRoot.node("a"); System.out.printf("\"a1\" exists: %s%n", a.nodeExists("a1")); Preferences a1 = a.node("a1"); a.flush(); a1.removeNode(); } } [3] http://download.java.net/java/jdk9/docs/api/java/util/prefs/Preferences.html
