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Comparing boxed Long values 127 and 128
... If the data type of above variable is primitive (long) then code work for all values.
Java caches Integer objects instances from the range -128 to 127. That said:
If you set to N Long variables the value 127 (cached), the same object instance will be pointed by all references. (N variables, 1 i...
MySQL Results as comma separated list
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The intent is fine and MySQL will allow this, but be careful (generally) with your use of GROUP BY. The items in the select list need to be valid aggregates in the context of the GROUP BY clause. In this case, p.name is not strictly valid. Any database con...
Git - Pushing code to two remotes [duplicate]
...hes. However, you may add multiple pushurls for a given remote, which then allows you to push to multiple remotes using a single git push. You can verify this behavior below:
$ git clone git://original/repo.git
$ git remote -v
origin git://original/repo.git (fetch)
origin git://original/repo.git ...
Show percent % instead of counts in charts of categorical variables
...for 'ggplot count vs percentage histogram' so hopefully this helps distill all the information currently housed in comments on the accepted answer.
Remark: If hp is not set as a factor, ggplot returns:
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How does password salt help against a rainbow table attack?
... attack. However, the methods I've seen to implement this don't seem to really make the problem harder.
10 Answers
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Android Bitmap to Base64 String
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The problem with jeet's answer is that you load all bytes of the image into a byte array, which will likely crash the app in low-end devices. Instead, I would first write the image to a file and read it using Apache's Base64InputStream class. Then you can create the Base64...
Under what conditions is a JSESSIONID created?
...s created/sent when session is created. Session is created when your code calls request.getSession() or request.getSession(true) for the first time. If you just want to get the session, but not create it if it doesn't exist, use request.getSession(false) -- this will return you a session or null. In...
How to export revision history from mercurial or git to cvs?
...en we finish or maybe every once in a while we want to commit our code and all of our revision history to cvs. We don't have write access to the project's cvs repo so we can't commit very frequently. What tool can we use to export our revision history to cvs? Currently we were thinking of using git ...
how to exclude null values in array_agg like in string_agg using postgres?
...NC = fn_array_agg_notnull,
STYPE = ANYARRAY,
INITCOND = '{}'
);
Calling the second is (naturally) a little nicer looking than the first:
select array_agg_notnull(v) from x;
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String vs. StringBuilder
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I like this answer a lot, especially the advice to code for clarity before performance. As developers, we spend as much or more time reading code as we do writing it.
– Scott Lawrence
Sep 16 '08 at 18:18
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