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SPower
SPower presents ...

2012/6/30

Save it

A simple demo of how to save a string on UserInfo with a nice GUI.

I also use a password to protect your info. The standard password is now empty, so press enter directly. After that, you can change it for yourself. Your password is hatched (coded), using SHA1. That's really safe, because there's no way to unhash a password. So, REMEMBER YOUR PASSWORD!!

I used the matrix of Spilli scenario for the background, so thanks for that Spilli :).

I hope you like it.

3465 views / 5 in the last 7 days

7 votes | 0 in the last 7 days

Tags: mouse demo with-source saving info

open in greenfoot

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SPowerSPower

2012/12/22

Does it happen immediately when you reset it?
tylerstylers

2012/12/22

no when you click enter
danpostdanpost

2012/12/22

It may be that UserInfo is not available (which may occur even when a user is logged in). Try either saving the user name when you initially check for user login, or use 'isStorageAvailable' before using 'getUserName'.
shrucis1shrucis1

2013/11/11

Notice this little snippet of code: if (this.name.equals("SPower")) { Button butt = new Button(ADMIN_BUTTON); butt.setResponder(this); addObject(butt, getWidth() /2, getHeight() /2 +100); } that gives you the 'Admin Button' if your username is SPower. And this: public void banUser() { if (this.info != null) { this.info.setString(BANNING_INDEX, "" + System.currentTimeMillis()); this.info.store(); } }
SPowerSPower

2013/11/11

Really, I don't think that's bad. Your password is hashed, so I can't access it (you can't un-hash something). And also, banning a user only happens when you enter the wrong password too many times. Ok with all that? And if I wanted to use it to my own advantage, why would I post the source?
shrucis1shrucis1

2013/11/11

I don't quite understand what you mean when you say it's hashed, unless Greenfoot does that automatically when you store data, because it seems like it's just storing the password as a regular string. Regardless, it's not like anyone is storing important data on this scenario (unless they were stupid enough to use their greenfoot account password for this password) and I was just pointing out that it seems you have total control. I didn't mean to offend you in any way. Also, are people allowed to use your 'Saver' and 'Scoreboard' classes if they cite credit? Greenfoot seems pretty open with people sharing code for reuse in different context, although you can get a project removed for plagiarism.
SPowerSPower

2013/11/11

Well, hashing is essentially turning a lot of data into a small form, which is almost impossible to crack, because a small change results in a completely different hash (The code for to hash the passwords is in the Coder class). This means that you can only compare the hash of the entered password to the stored one, and check if they are the same: the same data always has the same hash. And I wasn't really offended :) And yes, of course you may use the classes! That's why I posted the source! And ScoreBoard is from the greenfoot team, not me. And if you want to know more about hashing, I saw a good video about it: https://www.youtube.com/watch?v=b4b8ktEV4Bg
danpostdanpost

2013/11/11

Only the owner of the scenario has access to other users UserInfo data. This does not mean that the scenario cannot be programmed to share some or all information of one user with another. My 'Private Messaging' scenario will display the names and profile pics of any user that has used the app; however restricts the sharing of the data stored (the 'score' field, the ten 'int' fields, and the five 'String' fields) to just one String field; and then, only if certain conditions exist (that communication is intended between the two users). I am the only one who can access all communications between the users because I wrote and uploaded the scenario onto the site. All in all, as far as total control, I would say that, yes, the author (or uploader) of a scenario has total access to all UserInfo data and controls what information is shared between users. The only thing the author cannot do (well, not very easily), is change what information is stored in the UserInfo data of other users. An author can program the scenario to alter the data for a user when they run the scenario while logged onto the site. Even if data is encoded, I cannot see how the key would not be accessible to the author (it would either have to be a programmed constant or it would have to be stored somewhere within the UserInfo data).
shrucis1shrucis1

2013/11/11

Thanks SPower! And danpost, I was just pointing out that he had total control; I understand how it works.
RidicolasRidicolas

2016/11/25

it says I'm logged out even though I'm not

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