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Downcasting in Java
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Downcasting is allowed when there is a possibility that it succeeds at run time:
Object o = getSomeObject(),
String s = (String) o; // this is allowed because o could reference a String
In some cases this will not succeed:
Object o = new Object();
String s = (String) ...
Copying text with color from Notepad++
Is there a way to copy the text from a Notepad ++ file with color?
9 Answers
9
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How do I delete multiple rows in Entity Framework (without foreach)
I'm deleting several items from a table using Entity Framework. There isn't a foreign key / parent object so I can't handle this with OnDeleteCascade.
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Why no ICloneable?
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ICloneable is considered a bad API now, since it does not specify whether the result is a deep or a shallow copy. I think this is why they do not improve this interface.
You can probably do a typed cloning extension method, but I think it would require a different name ...
Bogus foreign key constraint fail
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Two possibilities:
There is a table within another schema ("database" in mysql terminology) which has a FK reference
The innodb internal data dictionary is out of sync with the mysql one.
You can see which table it was (one of them, ...
Clearing purchases from iOS in-app purchase sandbox for a test user
...mail address, password, secret question, secret answer, date of birth, and iTunes store country. You can put exactly the same data (including password) for tester+01@gmail.com and tester+02@gmail.com and you will have two test accounts. Finally, in your tester@gmail.com inbox you will receive two ...
Detect if Android device has Internet connection
...o network available!");
}
return false;
}
Of course you can substitute the http://www.google.com URL for any other server you want to connect to, or a server you know has a good uptime.
As Tony Cho also pointed out in this comment below, make sure you don't run this code on the main threa...
How to reload/refresh an element(image) in jQuery
Is it possible to reload an image with an identical file name from a server using jQuery?
12 Answers
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Tar a directory, but don't store full absolute paths in the archive
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tar -cjf site1.tar.bz2 -C /var/www/site1 .
In the above example, tar will change to directory /var/www/site1 before doing its thing because the option -C /var/www/site1 was given.
From man tar:
OTHER OPTIONS
-C, --directory DIR
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What is the best way to compute trending topics or tags?
Many sites offer some statistics like "The hottest topics in the last 24h". For example, Topix.com shows this in its section "News Trends". There, you can see the topics which have the fastest growing number of mentions.
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