Having met many experts in the field, and watched thousands of videos, believe me, Ranjith and his vidoes are my favorite. I feel like the world kind of hides a diamond inside it. Ranjith, I'm sending my love and appreciation to you. Wish you a beautiful life, together with your family and kids, who are, I'm sure, brilliant as much as you.
Really Great Work, Sir !! I am in this field for around 5 years and I can undoubtedly say that this is BEST tutorial for anyone to learn Singleton in all the depths possible !! Cheers !!
Appreciate your valuable thoughtfulness in explaining the issues with Singleton and fixing the same!!! Best one that is available out there!!! Keep up the good work!!!
Underrated channel, trust me when i have been trying to dig deepest into Java since a couple of yrs. This is yrs of knowledge in this video. Do you still make videos? Pls do...
I was literally clapping at the send of the video , excellent intro to Singleton Pattern , thanks a lot . Can you if possible , throw more insight into the best practices for multi-threaded coding in Java or general.
This was really an in-depth video about the Singleton pattern. I would say this was the best explanation I have seen till now. Great work Ranjith. I request you to please upload more videos on your channel. So that we can learn and grow from your knowledge.
Thanks Ranjith for this excellent material on Singleton. I believe this is one of the most common yet misunderstood pattern in programming. Your video series simplifies many of the complex notions built around it. Kudos.
Hello Sir...your session is really motivation for us. Explanation is really well. Nowhere I can find this much of clear and crisp Explanation. Could you please continue making videos for us latest technologies.
hi ranjith..very very nice and detailed explaination..i have watched all of your vedios...please publish vedios of such kind of expalination for all design patterns you have sumerized in high level distribution of design patterns in one of your vedios...awating of your next vedios on designp
Thanks Ranjith for such an awesome explanation. This is very helpful for every one who want to learn Singleton pattern. Even all your videos on java are excellent. But those are very limited. I am requesting you to please upload java videos as many you can so that it will help us a lot to improve our knowledge...Please..Thanks again for such a wonderful videos.
How can you be so awesome? Hands down, this is one of the best tech channel I subscribed in recent times. Are you on facebook or twitter ? I don't want to miss any updates from you
This solution is fine only. We can also modify the constructor part and that will suffice. Like: private Singleton() { if(soleInstance != null) { throw new RuntimeException("instance already exists. Thus this re-creation is not allowed."); } else { soleInstance = new Singleton(); System.out.println("creating singleton instance"); }
ranjith excellent explaination about singleton. I have seen other videos from you also. All of them are very well covered. Thank you for doing this. I have a request for you. kindly cover units tests also in some video. Please cover various possible situations in that like how to test static classes and static methods. Also how will you go about testing the web application controllers and database related code classes
Excellent Tutorial Ranjith. Really Appreciate your in depth Knowledge on this concept. Please Suggest the books that you refer to get this kind of in depth analysis on Core Java Concepts. Thank you and once again super knowledge sharing keep continue..
Hi Ranjith, Its great explanation, appreciate that. Any thoughts on if new thread try to load it with Class.forName("package.Singleton.class") at some places of invocation in the application will that creates new object/instace for new threads? and what happens to existing instances/reference?
Thank you Ranjith for such a good videos. As you said, we'll have a discussion in comment section regarding the solution for violating singleton rules by creating the instance(s3) and then s1, s2 using Reflection. How can we restrict multiple instances and maintain Singleton pattern? Please answer.
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
Thank you very much for the tutorial Ranjith. Very informative. Apart from the tutorial, I was curious what font do you use in your IDE. Could you please tell the name of the font?
Hi Ranjith,. Thanks for the clear information on Singleton Design pattern , Here i have tried the way you mentioned when we move the reflection code before creating the first two instances. and executed then Its creating an instance for reflection as well which has a different hash code and proceeding with creation of next 2 instances with different hash code for both instances . Please advise ,. on how can we overcome this.
+Ranjith ramachandran I have just started watching your videos and I am done with all of them now, and waiting for new one's. I do appreciate your effort on making the video.. if you can spare some time.. that will be great help for developers to learn a thing or two. and thanks again for tutorials..
Awesome Explanation on Singleton Design Pattern.......... Thanks Ranjith, I will be very happy if you come up with few more design pattern tutorials, Are you thinking of this?
+Piyush Asopa Thanks. Please subscribe to the channel for updates. I already have one on factory -method, please check it out th-cam.com/video/EdIwFK0gCm4/w-d-xo.html
Hello Ranjith, I am missing your videos. I guess all the subscribed persons are also missing your videos. I tried searching your profile in other social websites as well. Can you please come back to youtube? Its also fine if you have paid video series we are willing to enroll, let us know any series if you have. Thanks once again. Awesome work.
Great Explanation. qq#. When we use Reflection to get an Instance, If we keep the reflection code before those Singleton.getInstance(); We are getting the different Instances for Reflection and also for Singleton.getInstance(). How can we restrict to create more than one Instance using Reflection also.
I was expecting all three singleton objects to have to same hashcodes but the first one using reflection has a different hashcode than the ones using getInstance. Why?
Nice video ranjit.you explain really well. Thank you for such a nice video. I would like to know how can we fix the issue of creating an instance thru reflection when we place the code at the beginning of main method.thanks in advance.
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
Firstly thanks for tutorial Ranjith.What if the reflection call is there before getInstance method() call? There two instances of Singleton class is getting created.How to prevent that?
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
@@rohitborate9824 @Rohit Borate Okay but how to get hold of the instance already created? In case the instance is created through reflection is there any way to get hold of that instance in Singleton class?
It's the best explanation i have ever seen on the web about the singleton design pattern. I have one query, the way you have followed to avoid singleton breaking by reflection will not work if the first instance is created by reflection and second instance is created by getInstance() method. Could you suggest any way to avoid this as well?
In the constructor, if you are not throwing an exception, you can assign the value of the private static variable as this, like below private static Singleton singleton; private Singleton() { if (singleton != null) { throw new RuntimeException("Cannot create an instance of Singleton, please use getSingleton method"); } singleton = this; }
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
In which conditions we need a Single ton class to be serializable or clonable . If we do't want than can we prevent it by not implementing the interfaces ...
Hi Ranjith, I have a question. If we have a scenario where we are having 2 threads, one thread using reflection to get an instance and other using global point of access getInstance() method. Can it still break the code u have provided to take care of reflection.
Having met many experts in the field, and watched thousands of videos, believe me, Ranjith and his vidoes are my favorite. I feel like the world kind of hides a diamond inside it.
Ranjith, I'm sending my love and appreciation to you. Wish you a beautiful life, together with your family and kids, who are, I'm sure, brilliant as much as you.
This man is undoubtedly a Java Guru. Deserves much more views and subscribers !!
Excellent job. Very well explained. Taking into account that this is a free video makes your work even more impressive. Respect.
Sir you are GOD of java tech.... and that too free content of this level, hats off !!
Great explanation i have never seen such a good explanaiton. Great job. Can u please some videos on Thread to improve thread concepts
Mass Thala, Never seen such an explanantion, Just by seeing the few videos you posted gained immense knowledge. Love from madurai :)
your every word is pure and contains tons of experience/information, thanks for creating such videos. please create more.
Really Great Work, Sir !! I am in this field for around 5 years and I can undoubtedly say that this is BEST tutorial for anyone to learn Singleton in all the depths possible !! Cheers !!
I have never seen this much deep explanation for Singleton..Great.Thank you so much.Waiting for other design pattern videos.
This Person deserves a thumps up !
very well and extensive explanation. some tutorial hard to explain basic concepts, but this video can explain complex concepts clearly. respect
Appreciate your valuable thoughtfulness in explaining the issues with Singleton and fixing the same!!! Best one that is available out there!!! Keep up the good work!!!
your explanations and knowledge in the topic is off the charts sir !
Underrated channel, trust me when i have been trying to dig deepest into Java since a couple of yrs. This is yrs of knowledge in this video. Do you still make videos? Pls do...
Awesome sirji.. you have put lot of efforts to explained.... and very nicely explained..
Great explanation and handled all the possible scenarios for Singleton. Thumbs up!!!!
I was literally clapping at the send of the video , excellent intro to Singleton Pattern , thanks a lot . Can you if possible , throw more insight into the best practices for multi-threaded coding in Java or general.
This was really an in-depth video about the Singleton pattern. I would say this was the best explanation I have seen till now. Great work Ranjith. I request you to please upload more videos on your channel. So that we can learn and grow from your knowledge.
Thanks Ranjith for this excellent material on Singleton. I believe this is one of the most common yet misunderstood pattern in programming. Your video series simplifies many of the complex notions built around it. Kudos.
happy2k thanks for the feedback; yes, most of us takes singleton as the example of design pattern they used, meanwhile it is very hard to get right!
Really .. really helpful video to understand the singleton and its complex behavior in different scenarios in one go... thanks a lot !!!!
One of the best explanations I have ever seen....Thanks Ranjith
Good and precise content , please keep the videos coming .
Hello Sir...your session is really motivation for us. Explanation is really well. Nowhere I can find this much of clear and crisp Explanation. Could you please continue making videos for us latest technologies.
Excellent Video Ranjith. Best one so far on web which explains in detail with code from violation standpoint. Thank You!
FAN of your teaching !! crystal clear with Singleton concept ! great work on video. Keep it up dude !!!
never seen this much deep explanation.
i wonder why u stop making videos.
u helped us alot Thanks
Ranjith, you explained things very well why we have very less number of videos from your end.
Awaiting more such videos to learn Java from your end..
Really Nice one , Gone through all your video... w8 for more.
Thanks Ranjith for crystal clear about Singleton.Most of the doubts got cleared!!!!
Detailed Explanation with easy Example. Thank you, Sir
Ranjith you are awesome. Thanks for your practical explanation.
Thanks for the facts and solution given after first video
@Ranjith i found your videos have the best explanation on Singletons i found so far. Thanks , keep up the good work.
@7:29 "But still I would prefer throwing exception thing. Because ....Personal choice"....That's called swag with intelligence....
One of the best java videos on youtube. Hats off !
very well explained
Nice and Simple explanation. Thank you.
Sir, could you pls continue making videos on rest of the design patterns as well ?
It was really awesome, really enjoyed both the episodes. Keep up the good work.
Thank you so much Ranjith. Hats off to you.
Really Really Awesome Explanation..... I have ever heard.. FYi I have subscribed.. Thank You So much for sharing knowledge..
thanks sir , the singleton videos are best
waiting for more sir....
Very well explained with crystal clear concepts. Thank you so much for this sir. :)
It's simply Awesome explanation.. Thank you Ranjith.
hi ranjith..very very nice and detailed explaination..i have watched all of your vedios...please publish vedios of such kind of expalination for all design patterns you have sumerized in high level distribution of design patterns in one of your vedios...awating of your next vedios on designp
Thanks Ranjith for such an awesome explanation. This is very helpful for every one who want to learn Singleton pattern. Even all your videos on java are excellent. But those are very limited. I am requesting you to please upload java videos as many you can so that it will help us a lot to improve our knowledge...Please..Thanks again for such a wonderful videos.
Super Ranjith , videos are good and informative.Please make videos on other design patterns as well apart from the factory you have made.
Excellent Job, Hats off
Excellent, no words to say.
great tutorial with clear explanation. why new videos are not coming ?
Thanks a lot.. its helps me a lot to understand the concept.
great work ! perfect that you explained that subject so thoroughly with many different aspects, thank you :)
Man, you rocked. Great explanation. keep going.
Thanks for the videos. Its very helpful.
Hello Sir, your all videos are so well explained and very helpful.
Could you please post more videos.
Thank you so much for sharing video.
How can you be so awesome? Hands down, this is one of the best tech channel I subscribed in recent times.
Are you on facebook or twitter ? I don't want to miss any updates from you
Very good explanation..!
Excellent ,this really helped.
best tutorial :) awesome thanks alot Ranjith :)
Thanks for the videos. very helpful.
This solution is fine only. We can also modify the constructor part and that will suffice. Like:
private Singleton() {
if(soleInstance != null) {
throw new RuntimeException("instance already exists. Thus this re-creation is not allowed.");
} else {
soleInstance = new Singleton();
System.out.println("creating singleton instance");
}
Very cool video.
Thanks a lot, very well explained..
ranjith excellent explaination about singleton. I have seen other videos from you also. All of them are very well covered. Thank you for doing this. I have a request for you. kindly cover units tests also in some video. Please cover various possible situations in that like how to test static classes and static methods. Also how will you go about testing the web application controllers and database related code classes
Very well Explained Sir..
But why u stopped making videos sir..
Hi Ranjit,
Awesome Explanation on Singleton Design Pattern....Here, it is not clear the flexibility benefit.Can u explore these also.
Excellent Tutorial Ranjith. Really Appreciate your in depth Knowledge on this concept. Please Suggest the books that you refer to get this kind of in depth analysis on Core Java Concepts. Thank you and once again super knowledge sharing keep continue..
Its Very useful , if possible can you please explain multi threading in next vedeo
Thank you so much for the awesome tutorial :)
Hi Ranjith, Its great explanation, appreciate that. Any thoughts on if new thread try to load it with Class.forName("package.Singleton.class") at some places of invocation in the application will that creates new object/instace for new threads? and what happens to existing instances/reference?
Thanks Ranjith for the awesome video. Solution for the multiple class loader problem has not been addressed. Can you put some light on same.
Thank you Ranjith for such a good videos. As you said, we'll have a discussion in comment section regarding the solution for violating singleton rules by creating the instance(s3) and then s1, s2 using Reflection. How can we restrict multiple instances and maintain Singleton pattern? Please answer.
did you find the solution ?
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
Thanks Ranjith...
Thank you very much for the tutorial Ranjith. Very informative. Apart from the tutorial, I was curious what font do you use in your IDE. Could you please tell the name of the font?
Awesome
Hi Ranjith,. Thanks for the clear information on Singleton Design pattern , Here i have tried the way you mentioned when we move the reflection code before creating the first two instances. and executed then Its creating an instance for reflection as well which has a different hash code and proceeding with creation of next 2 instances with different hash code for both instances . Please advise ,. on how can we overcome this.
Best tutorial!!!
Thanks Ranjith... Really a best one ... How can we come to know of your future releases?
+Manas Sinha Please subscribe to the channel. As a new year resolution, there will be at least 2 vids per month.
Ok thanks...already subscribed...
+Ranjith ramachandran I have just started watching your videos and I am done with all of them now, and waiting for new one's. I do appreciate your effort on making the video.. if you can spare some time.. that will be great help for developers to learn a thing or two.
and thanks again for tutorials..
:( you broke your resolution :(
Awesome Explanation on Singleton Design Pattern.......... Thanks Ranjith,
I will be very happy if you come up with few more design pattern tutorials, Are you thinking of this?
+Piyush Asopa Thanks. Please subscribe to the channel for updates. I already have one on factory -method, please check it out th-cam.com/video/EdIwFK0gCm4/w-d-xo.html
please make more videos, it's very less. your videos have depth analysis of concept which is helpful for working professionals also
We are awaiting for you next release of other design patterns Mr.Ranjith :)
Hello Ranjith, I am missing your videos. I guess all the subscribed persons are also missing your videos. I tried searching your profile in other social websites as well. Can you please come back to youtube? Its also fine if you have paid video series we are willing to enroll, let us know any series if you have. Thanks once again. Awesome work.
Very nice tutorial sir.. :)
can you tell me which software you are using to share screen..?
Nice one
Hi Brother :)
Your videos are very good.
Can you make other design pattern videos
Great Explanation.
qq#. When we use Reflection to get an Instance, If we keep the reflection code before those Singleton.getInstance(); We are getting the different Instances for Reflection and also for Singleton.getInstance(). How can we restrict to create more than one Instance using Reflection also.
use like:-
private Singleton() {
throw new RuntimeException("Instance already created please use getInstance()");
}
private Singleton(boolean actualCreationCall) {
System.out.println("Only Object Created");
}
public static Singleton getInstance() {
if(onlyObject == null) {
onlyObject = new Singleton(true);
}
return onlyObject;
}
more patterns, please.
3:54 - pastebin.com/sb19AZQd
helpfull comment thankyou dude..... i got output which i have expected
I was expecting all three singleton objects to have to same hashcodes but the first one using reflection has a different hashcode than the ones using getInstance. Why?
Nice video ranjit.you explain really well. Thank you for such a nice video. I would like to know how can we fix the issue of creating an instance thru reflection when we place the code at the beginning of main method.thanks in advance.
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
Superb video SIr! Thanks a lot.
What's the answer to the question at 3:47
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
awesome!
Firstly thanks for tutorial Ranjith.What if the reflection call is there before getInstance method() call?
There two instances of Singleton class is getting created.How to prevent that?
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
@@rohitborate9824 @Rohit Borate Okay but how to get hold of the instance already created? In case the instance is created through reflection is there any way to get hold of that instance in Singleton class?
It's the best explanation i have ever seen on the web about the singleton design pattern. I have one query, the way you have followed to avoid singleton breaking by reflection will not work if the first instance is created by reflection and second instance is created by getInstance() method. Could you suggest any way to avoid this as well?
In the constructor, if you are not throwing an exception, you can assign the value of the private static variable as this, like below
private static Singleton singleton;
private Singleton() {
if (singleton != null) {
throw new RuntimeException("Cannot create an instance of Singleton, please use getSingleton method");
}
singleton = this;
}
One way is by creating a Static boolean flag and set it TRUE in constructor when constructor executes successfully for the first time. You can use this flag in getInstance method to check if object is already created or not. If flag is TRUE that means object is already created and you don't need to create an Object. Here you can throw runtime Exception.
Hi Ranjith,
thums up for your efforts,
which tool did you use to record this video?
Thanks,
Nishita
In which conditions we need a Single ton class to be serializable or clonable . If we do't want than can we prevent it by not implementing the interfaces ...
Great tutorials. Why aren't you making more?!
+Collected Reader :) In progress. Releasing new video very soon.
You are genius
Hi Ranjith, I have a question. If we have a scenario where we are having 2 threads, one thread using reflection to get an instance and other using global point of access getInstance() method.
Can it still break the code u have provided to take care of reflection.
Hey Ranjith !! It's really excellent . Keep post for new topics.
nice....