ATM program that loses data every execution - java

I am working on an ATM program. I have everything working and everything coded correctly. I press execute and can deposit/withdraw funds and have it be reflected with proper messages. When I hit execute again, everything is reset(account balances) and it shows nothing was withdrawn or deposited. How to I fix this? I was looking on here and thought maybe if I serialized some classes or something, it might work. It didn't.What can I do? When I hit execute, I want all of my deposits and withdrawals to still be effective. not lost.

You could make a menu-driven program where you can see all the changes you need from your program, but this only exist for the lifetime of the running program, once you restart the program you will sure loose the all previous content, If you don't want to loose the data after every execution you need a consistent storage like a database or file where you can read n write or update each time you run it

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Uncommon question with "Ethical hacking" challenge

I have a rather unusual question, but I still don't understand much in programming to understand if it is possible to do what I want. So I feel like I need a little story. My name is Nick, I live in Ukraine and am currently studying as a student in one of the IT firms. Now is the middle of my studies and, if everything goes good, they will give me a chance to get a job in 2 months. But not only me, but 300 more students from all over the country, since the training is online, and the company in which we will get one of the largest in the CIS.
This is where I come closer to the task. To complete the course, we have to complete 8 practical sessions with 5-6 tasks in each. Upon their implementation, we upload the code to the git lab. For this, the company has opened an account for each of us. Then the electronic program for checking assignments - E-Mentor compiles our code, provides input data to fill each class and checks the task. In case of an error, it creates log, which often does not provide complete information. Since some of the test data is always hidden. At the end, the program sets progress points for us. And we all want to get 100%)
**Task: Get input data from the E-Mentor server in the form of a file and automatically push it from the server side to my Git Lab account.**
I am not asking for the complete code, but I am asking you to help me write pseudo code so that I can implement it in full.
I represent it like this:
The server clones my code
Compiles it
Runs tests
At this time, a file is created that copies all incoming information from tests
Somehow the created file is being pushed to my gitlab
For example:
GitBash is started on the server and logs into the gitlab under my login. In this case, it is restricted to rewrite the password and login used by the server itself, as it will be immediately noticed.
This is the coolest challenge that I want to try to do and share it with all students)

How to make program output differently depending on number of runs?

This is not like a code help or code review thing.I am trying to make a counter for my program that can define the output of my program.For eg: If i want my program do specific thing after it has been run two times or else it should do another thing.Another example of what i am trying to say is that when i run my program first and second time it should print 3,but when i run it third time it should print 5.
I believe there are many ways already out there,but i don't know how to search such type of specific query on google.
I am working on complex program,where such type of thing is required,but i don't know where and how to start or look.I tried to make a counter,but every time the program runs,it initializes the value of counter and so it doesn't increment.
You have to maintain a state of the each time it runs. It means in the program, maintain a counter and store it in a file. You can do it in the following way.
If there is running state counter stored in a file, it means the application is run first time.
Before running the application, read the file which maintains running counter.
Based upon the running counter number like even , odd etc, you can write the logic.
You have to save the value in a file or some other storage method that persists after the program runs and ends.
Every time the program runs:
If there's no file, then create one and write the number 1 in it to show that the program has run once.
If there is already a file when you run the program, then read the number stored in it and interpret it as the number of previous runs. Write a number to the file that is 1 higher than the number of previous runs.

Firebase Jobdispatcher - to use or not to use

I am developing an App, a simple, but hopefully addictive little game. The user has to solve predefined levels, as quick as possible.
Information on the levels is stored online in an MySQL database, which also contains the average time it took all players to complete a given level. Also, the level-data is stored, locally, in a SQlite database on the phone.
What I want to do is the following. I want to synchronize the average time (from server to phone) and upload the time it took a player to complete a leve (from phone to server).
Ideally this happens each time the player starts the app or finishes a level. For this, I am considering a Firebase Jobdispatcher, but I was wondering if this is overkill or not. For your information: it is not the end of the world if the average time stored on the phone is not entirely up to date. The game will work just fine without it being up to date. On the other hand, I want it to get updated regularly as the performance of the user will be compared to the average time.
I am a beginner, who wants to do things correctly. Hope you can help.
It sounds like you already know when some work should happen. As you said:
Ideally this happens each time the player starts the app or finishes a level.
You don't need JobDispatcher to schedule work when you are already in control of the times when the work should happen. JobDispatcher is used when you need to schedule some work at some point in time or interval when your app may not even be running.

Java update panel for all users upon database change

So I have a program that runs on multiple computers. The program connects to a server where it gets all of its data from. There's a JPanel which lists names from a table in my postgresql database. As of now, the only way to refresh the panel is with a button press. I want the panel to update on its own when there is a change in the database so if one user adds a name, the other users will be able to see the change right away. Is there a way to broadcast a message to all users that are connected to the server so that their panel can refresh?
As soon as you want to do something like this you enter the world of multiple threads and all kinds of havock. Your question does not really have anything to do with databases, you merely want to send a message to all others using the application to update a component when they need to, keep your concerns separate. Now then you need to ask some questions like are the users all on the same network? Then you can get away with a simple chat client for java, there are heaps of them out there. But think about it, do you really need this requirement? Can't you just update the table say every 10 seconds? Or every 5 seconds? The difference in the difficulty of the implementation is substantial but the result I would say would be very similiar, unnoticable to the user even. But maybe you just want to learn stuff, then maybe you think you should add another table in sql with one entry which records the time the user table was updated which you can check and will be more optimal than the other. But this is considered bad practice, do you care? Same with sql statements to check when a table was edited last from what I have seen on the net, but should we always apply best practices, the application will still get across the line.
Maybe your update button is not looking so bad after all.
But users complain about that sort of crap and you can't explain this stuff to every user. My suggestion would be to have a configurable update that runs every how ever many seconds you tell it to. You will have to look up stuff about multi-threading though but shouldn't be too horrible.

Is it possible to modify the time OSCeleton sends a lost_user event/message?

I'm playing around with OSCeleton and Processing and succesfully got to track skeletons and do stuff.
What I'm wondering is if there's any way to change the delay time a "lost_user" message is sent to Processing.
This is taking so long for what I'm trying to achive, since i need to stop tracking a user as soon as he goes away from the screen, so I can accept another user's interaction. (imagine an installation where a lot of people wants to play with).
any help/tips would be really appreciated.
Jon
As far as I can tell from the OSCeleton's source and with my minimal experience with the kinect(I never used OSCeleton), there is no way to modify that code to do that. It seems to be a thing handled even lower, by the driver or by the kinect its self(?).
Yet you need not bind yourself with that, and I would suggest a couple of ways to bypass the problem if I understand properly.
First, the latest drivers and examples should have multi-user support, meaning you can just arrange who is your main user. From what I can tell from the source you do get an osc message in Processing when a new user is detected as well as an ID number. You can put each new user that arrives, into an arrayList and figure out a way to do things without depending on the latest user.
If you are still going for the user-after-user thing though, or I was mistaken about the multi-user support(which is mentioned nowhere in the README), you can check yourself whether a user has left the area. Although you can not get a definitive answer like that you can check for example, whether a specific joint or all joints of a user have moved in the last 10-20 osc messages received. That probably means storing the position of this joint in an 10-20 item array and continuously updating while also doing a check on whether the items are different. If all items in the array are the same, your user has not moved a bit and thus probably should not be taken to account.
Last but not least you can switch to other solutions. The one I used about a year ago was "Synapse for Kinect" which also seems stale now. The latest you can use is a Processing library called SimpleOpenNI which definitively have multi-user tracking and you won't need any intermediary programs running to give you the joints.
I hope this helps

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