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Identify duplicates in a List
...e method add of Set returns a boolean whether a value already exists (true if it does not exist, false if it already exists, see Set documentation).
So just iterate through all the values:
public Set<Integer> findDuplicates(List<Integer> listContainingDuplicates)
{
final Set<Inte...
I want my android application to be only run in portrait mode?
...
In the manifest, set this for all your activities:
<activity android:name=".YourActivity"
android:configChanges="orientation"
android:screenOrientation="portrait"/>
Let me explain:
With android:configChanges="orienta...
No Persistence provider for EntityManager named
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I am using Derby and it wasn't necessary to specify this (I did, but then removed it once I solved the problem, just to make sure). I was getting the error finally because persistence.xml was not in the src/META-INF folder, even though it had been in a folder in the Eclips...
How to design a database for User Defined Fields?
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If performance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access pa...
Count the number of occurrences of a character in a string in Javascript
...g")) || []).length); //logs 4
jsfiddle
Use a regular expression literal if you know what you are searching for beforehand, if not you can use the RegExp constructor, and pass in the g flag as an argument.
match returns null with no results thus the || []
The original answer I made in 2009 is be...
How to prevent Browser cache for php site
... Except for "max-age=0", those are the headers sent by PHP without specifying the above in my installation.. It seems PHP tries to prevent browser caching by default...
– fast-reflexes
May 19 '13 at 10:03
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Why does my application spend 24% of its life doing a null check?
... not a perfect solution. The processor will still stall on a memory access if the data is not available in one of the caches. It cannot continue until the very slow memory bus has supplied the data. Losing a fat hundred CPU cycles is possible on a single instruction.
Tree structures are a problem, ...
What is the session's “secret” option?
...ior express-session since 1.11.0 supports secret rotation. From the docs: "If an array of secrets is provided, only the first element will be used to sign the session ID cookie, while all the elements will be considered when verifying the signature in requests." (See expressjs/session#127 for detail...
How to permanently remove few commits from remote branch
...g it)
This SO answer illustrates the danger of such a command, especially if people depends on the remote history for their own local repos.
You need to be prepared to point out people to the RECOVERING FROM UPSTREAM REBASE section of the git rebase man page
With Git 2.23 (August 2019, nine year...
Why does 0.ToString(“#.##”) return an empty string instead of 0.00 or at least 0?
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# in the string format indicate that the value is optional. If you wish to get the output 0.00 you need the following:
0.ToString("0.00");
See here for the custom numeric formats that can be passed to this method.
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