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Treeset Cannot Be


The set will be empty after this call returns. Can a president win the electoral college and lose the popular vote Why is the 'You talking to me' speech from the movie 'Taxi Driver' so famous? Specified by: pollLastin interfaceNavigableSet<E> Returns:the last element, or null if this set is emptySince: 1.6 clone publicObjectclone() Returns a shallow copy Build me a brick wall! http://rinfix.com/cannot-be/treeset-cannot.html

But why this is required only for TreeSet class ?? Hmmm. super T, ? So can you point me to the right direction to custon a Comparator to solve the problem, I love challenges so would you give me a few Hints Pealse Rob More hints

Cannot Be Cast To Java.lang.comparable Treemap

I just want to use a Set to filter the unique elements of the List since my List contains unncessary duplicates. –Chuck Mar 24 '10 at 1:40 2 Use a Use is subject to license terms. Regarding thread-safety I also see no problem. How good should one be to participate in PS?

  1. Professor Lewin: "Which string will break?" / Me: "That one." / Professor Lewin: "Wrong!" Isn't AES-NI useless because now the key length need to be longer?
  2. All elements inserted into the set must be mutually comparable by the specified comparator: comparator.compare(e1, e2) must not throw a ClassCastException for any elements e1 and e2 in the set.
  3. Specified by: floorin interfaceNavigableSet<E> Parameters:e - the value to match Returns:the greatest element less than or equal to e, or null
  4. Related 1Accessing elements in a treeset6Why does TreeSet throws ClassCastException0JAVA: objet Set:: error with the first .add(object)1How to retrieve elements from sorted TreeSet using Binary Search?0Why can't I use .pollFirst() method
  5. share|improve this answer edited Mar 2 '14 at 4:18 answered Mar 2 '14 at 4:12 Erwin Bolwidt 12.7k92436 Erwin, I appreciate you taking your time for that thorough answer.

Given the definition of your class, how would TreeSet know how to sort instances of it? [Asking smart questions] [About Bear] [Books by Bear] Laythe Chamse Greenhorn Posts: 15 posted kag0 commented Oct 1, 2016 Doesn't the lazy comparator have the same issue ruslan pointed out? Set s = new TreeSet(); s.add(new Employee(1001)); Or Set s = new HashSet(); s.add(new Employee(1001)); s.add(new Employee(1002)); Then result is success there is no exception. Treeset Comparator Regards.

super E>> create() { return new TreeSet(); } public static TreeSet create(Comparatorequals, hashCode, removeAll Methods inherited from classjava.util.AbstractCollection containsAll, retainAll, toArray, toArray, toString Methods inherited from classjava.lang.Object finalize, http://stackoverflow.com/questions/2504803/list-to-treeset-conversion-produces-java-lang-classcastexception-myclass-cann Program Creek R Research Machine Learning Contact Simple Java Java 8 Coding Interview Java Java Basics Java Object Oriented Concepts Java Collections & Generics Java File I/O Java Database Java Multi-Threading

However, I tend to use a static cache because the number of types of an application that implement comparable are finite and searching the hierarchy is relatively cost-intensive. Treeset Vs Hashset I will come back to this issue during this week (because of too many parallel tasks already). - Daniel JΛVΛSLΛNG member danieldietrich commented Sep 28, 2016 • edited I agree that Agreed. If TreeSet / TreeMap could be changed completely, they should have no public constructors but factory methods instead (the constructors become private): public static

Treeset Comparable Example

That would explain your problem, because TreeSet would then think that all your objects are 'the same' based on the compareTo method result. https://docs.oracle.com/javase/7/docs/api/java/util/TreeSet.html Comment 7 Peter Nabbefeld 2011-09-28 08:04:34 UTC Created attachment 111267 [details] stacktrace Comment 8 Peter Nabbefeld 2011-09-30 08:45:37 UTC (In reply to comment #5) > As you know, recent daily builds Cannot Be Cast To Java.lang.comparable Treemap Sponsored by Cannot Be Cast To Java.lang.comparable Java Then this might be the problem: http://statistics.netbeans.org/analytics/detail.do?id=180961 > ...

public class Comparator implements java.util.Comparator { public int compare(Object o1, Object o2) { if(o1 == o2) return 0; if((o1 != null && o1.equals(o2)) || (o2 != null && o2.equals(o1))) return 0; extends T1, ? If either set is modified while an iteration over either set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. Then the resulting SortedSet would be equivalent to an unordered Set. Treeset Example

If you want to sort using different order then you need to provide your own comparator. Implementations may, but are not required to, throw this exception if fromElement or toElement cannot be compared to elements currently in the set. NullPointerException - if fromElement Is there a way to block a President Elect from entering office? this contact form The returned set supports all optional set operations that this set supports.

Description Peter Nabbefeld 2011-09-19 06:41:00 UTC Build: NetBeans IDE Dev (Build nbms-and-javadoc-7840-on-20110906) VM: Java HotSpot(TM) Client VM, 21.0-b17, Java(TM) SE Runtime Environment, 1.7.0-b147 OS: Windows XP User Comments: epdv: Please, add Treeset Java super T, ? The returned set is backed by this set, so changes in the returned set are reflected in this set, and vice-versa.

In fact I do not plan to break anything in near future (opposed than stated in one of my previous blog posts).

Comparator in Java Sort LinkedList of User-Defined Objects in Java Category >> Collections If you want someone to read your code, please put the code inside

tags. kag0 commented Oct 7, 2016 if (hash1 < hash2) { return -1; } else if (hash1 > hash2) { return 1; } This seems reasonable. JΛVΛSLΛNG member danieldietrich commented Mar 24, 2016 Yes, great idea, I think it should be possible. Java 8 Treeset Laythe Chamse Greenhorn Posts: 15 posted 7 years ago David Newton wrote:Depends--how do you want MyOwnClass to be compared to other instances?

Symmetric group action on Young Tableaux why does this error keep popping out? Note I based this compareTo method on your equals method. Here is the example: public class TreeSetTest { @Test public void testFlapMap() { final TreeSet objs = TreeSet.ofAll((o1, o2) -> o1.field.compareTo(o2.field), Stream.of("o1", "o2").map(Obj::new) ); // That works as you're using a navigate here Note that the ordering maintained by a set (whether or not an explicit comparator is provided) must be consistent with equals if it is to correctly implement the Set interface. (See

Copyright © 1993, 2016, Oracle and/or its affiliates. Both plugins (MM, MMR) are just weekend projects, not part of NetBeans distribution, published on Update Center for plugins in Beta quality. BTW reporter you are running a mixture of modules from various dev builds (not to mention lots of third-party modules which look to be long outdated). Collections.sort(List) has been able to prevent this using generics, but TreeSet / TreeMap couldn't.

Just to give you a hint that think in terms of adding an object and you are good.