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javax.validation.ValidationException: HV000183: Unable to load 'javax.el.ExpressionFactory'
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It is working after adding to pom.xml following dependencies:
<dependency>
<groupId>javax.el</groupId>
<artifactId>javax.el-api</artifactId>
<version>2.2.4</version>
</dependency>
<dep...
Is there some way to PUSH data from web server to browser?
...rver frequently to find whether there is new data. This increases server load.
18 Answers
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Is arr.__len__() the preferred way to get the length of an array in Python?
...es didn't all need to explicitly implement a public .length() method, instead you can just check the len() of anything that implements the 'magic' __len__() method.
Sure, this may seem redundant, but length checking implementations can vary considerably, even within the same language. It's not unco...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...ry optimizer would have to catch the fact that your GROUP BY is not taking advantage of any group members, just their keys. DISTINCT makes this explicit, so you can get away with a slightly dumber optimizer.
When in doubt, test!
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How to set input type date's default value to today?
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Machavity♦
27.5k1616 gold badges7171 silver badges8787 bronze badges
answered Aug 8 '11 at 13:19
TakTak
9...
How can two strings be concatenated?
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Community♦
111 silver badge
answered Aug 26 '11 at 8:50
RainerRainer
6,90511 gold badge1616 silver ba...
How to use NSJSONSerialization
...jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutableContainers error: &e];
if (!jsonArray) {
NSLog(@"Error parsing JSON: %@", e);
} else {
for(NSDictionary *item in jsonArray) {
NSLog(@"Item: %@", item);
}
}
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I had problems while "archiving" my app. I think there are invalid profiles because of iPhone Update to 5.1 and XCode update to 4.2.2.
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How do you kill all current connections to a SQL Server 2005 database?
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The reason that the approach that Adam suggested won't work is that during the time that you are looping over the active connections new one can be established, and you'll miss those. You could instead use the following approach which does not have this drawb...
How does the NSAutoreleasePool autorelease pool work?
...t is perfectly valid.
Every time -autorelease is sent to an object, it is added to the inner-most autorelease pool. When the pool is drained, it simply sends -release to all the objects in the pool.
Autorelease pools are simply a convenience that allows you to defer sending -release until "later"....