WebLogic 10.3 doesn't implements equals() and hashCode() for TimerHandle?

Hi,
I'm using WebLogic 10.3 and need to use TimerHandle to handle some logic in my application.
Below is a scenario.
At the time by creating EJB Timer, I've saved the TimerHandle for later use into Database along with specific name as a key.
Then, at the time to execute/awaken timer I need to check that the saved TimerHandle is the same as passed Timer.
@Timeout
public void execute( final Timer timer )
// getting key from passed object in timer.getInfo().
// getting saved timerhandle by key. let's say dao.getXxxHandle(key);
// perform checking.
if ( timerHandle != null && timerHandle.equals( timer.getHandle() ) )
// do sth.
else
//do another thing.
The result is always drop in else block.
By doing this is working on WAS7 and JBoss4xx (getting to if block). I was wondering if WebLogic doesn't implements equals and hashCode method then is there another way to check that the retrieved TimerHandle is the same one as timer.getHandle()?
I'm thinking of adding some unique ID to see if timehandle is the same one or not? However as I mentioned, It works on WAS and JBoss. Does WebLogic has another way to handle my scenario?
Any help would be appreciate.
Thanks in advance,
Nattachai W.

As you have suggested, it looks like we don't override the equals() method on either our local or clustered TimerHandle implementations.
We opened a bug (9558396) so we can address it in a future patchset.
In the meantime, if you have an Oracle support contract, you could open a service request and ask for a patch for bug 9558396 to be created.
-steve-

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Implementing equals() and hashcode

Hi,
I need to implement equals() and hashcode() in a class. I only need to use one class variable in the equals() method; String id.
I'm having difficulties to understand the examples I've seen - can someone please help me out?
regards, Puzz

And I know you said you had a hard time understanding some examples, but I'm not sure which examples you've seen. Here is some recommended reading that I think explains this concept well:
Sun's Java Tutorial: The equals and hashCode Methods
Josh Bloch: Effective Java
JavaWorld: Implementing equals and hashCode
IBM: Defining hashCode() and equals() effectively and correctly
JavaPractices: Implementing hashCode
JavaWorld: override hashcode/equals
~

Comparator question - changing Equals and HashCode too?

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public Double test()
return a * (1d / b);
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That depends if there are any class invarients that can be depended upon.
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Adding Objects To a HashSet, overriding equals and hashCode

Hi everyone,
I'm trying to add objects to a HashSet, using a string identifier (an attribute of these objects) to determine if two objects are equal.
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In fact you don't override the equals method. The signature defined in the Object class is
boolean equals(Object o)In your case it is
boolean equals(ExperimentalEvent e)So instead of overriding the method you're overloading it.
Regards

Why methods equals() and hashCode() is defined in Object Class?

Why methods equals() and hashCode() is defined in Object Class?

If you have two objects and you don't know (or care about) their exact types, but you still want to know if they are the same, then you can do something like this:
Object o1 = getObject1();
Object o2 = getObject2();
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// they are the same, do something
} else {
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If Object didn't have those methods, then you'd have to write that code against a more specific interface/class and it wouldn't be so general any more.

Overrideing equals() and hashCode()

This is related to my previous post. I have followed the advice that was given to me. I overrode equals() and hashcode()
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import java.util.*;
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Variable == Testing Value == true
Variable == Testing Value == true
Variable == Testing Value == true
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SquareBox wrote:
This is related to my previous post.An unrelated piece of advice that I was going to put in your previous thread (but it seems you've moved on):
Be careful how you name your classes.
'TwoTuple' may mean something to you, but it's not very descriptive to the rest of us. Furthermore, the word 'Tuple' suggests a very specific usage that isn't borne out in any of the methods you've implemented. What about 'Pair' or 'Couple' or 'Duo'? (In the world of names, shortest is usually best.)
Winston

HashSet - equals and hashCode

I must be missing the obvious over here..from what I understood of HashSet's/equals and hashCode, the program below should not add the Person object twice. Please suggest whats wrong...
import java.util.*;
public class TestHashSet2 {
Set set = null;
public TestHashSet2() {
set = new HashSet();
class Person {
String name;
Person(String name) {
this.name = name;
public boolean equals(Person person) {
if (name.equals(person.name)) {
return true;
} else {
return false;
public int hashCode() {
int code = name.length();
System.out.println(" HashCode: " + code);
return code;
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Person person1 = new Person("Mike");
set.add(person1);
Person person2 = new Person("Mike");
System.out.println(" person1 equals person2: " + person1.equals(person2));
set.add(person2);
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Iterator iterator = set.iterator();
Object obj = null;
while (iterator.hasNext()) {
obj = iterator.next();
System.out.println(" ELEMENT--> " + obj);
System.out.println(" Number of elements in set: " + set.size());
public static void main(String args[]) {
TestHashSet2 tSet = new TestHashSet2();
tSet.addPerson();
tSet.showPersons();
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the method equals(Person) has a different parameter type as equals(Object) and therefore doesn't override it. You need to change the method to equals(Object). This is a common 'gotcha' ...

Why Collection interface declares equals() and hashCode() method

When I went through the source code of Collection interface, I found equals() and hashCode() are declared? Why? If a class implements this interface, it will inherit these two method from Object, and we can true to override them.

It's probably so that they can provide the documentation that you see there.

How equals and hashCode fail here?

I have a set of Address objects. The pair of equals and hashCode are generated by Eclipse as the following:
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warnerja wrote:
The removeAddress method is implemented as the following:
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So you set the entry property to null (and presumably it wasn't null beforehand), and then invoke remove with that object. Well, since entry is one of the properties included in the criteria for equality, don't you see a problem with that? It can't find an object "equal" to that one, since the only ones it finds don't match ALL of the fields included in the equality criteria anymore, since you just wiped out one of them on the target object to find.
Here's another thing that looks suspect:
for(Address ae : entry.getAddresses()){
if(!entry.removeAddress( address ))
...Note the bolded parts. Anything strike you as odd?warnerja spotted my careless code. I shouldn't have address.setEntry(null); before the removal. After one attribute is changed, the object definitely is not the same again.
BTW, sorry for little bit messy on the sample code. I put together code from various classes to illustrate the problem.

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Overriding equals and hashCode

Everywhere I look it talks about overriding equals and hashCode together, and it also warns that doing it wrong could complicate things severly. However I haven't been able to find good documentation on how to do it properly.
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Comparing dynamic fields of objects using equals and hashCode methods

To compare the different objects of the same class with their contents like jobTitleId, classificationId, deptId & classificationId was to be done and do some manipulations later using Set and Map. I was able to do that by simply overriding the equals and hashCode methods of Object class and was able to fetch the information (like in the following Map).
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I'm thinking what if I override the same two methods `equals() & hashCode();`
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Problem in not overriding equals and Hashcode

I have a very small question. We know that if we do not override the equals and hascode of Object class, we can not use the object in the Hashed collection. Can anybody provide me a concrete example which indicates the problem if we do not override the equals and hascode.

back to the original question from DebadattaMishra
I have a very small question. We know that if we do
not override the equals and hascode of Object class,
we can not use the object in the Hashed collection.
Can anybody provide me a concrete example which
indicates the problem if we do not override the
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Hello,
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WebLogic 10.3 doesn't implements equals() and hashCode() for TimerHandle?

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