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explicit casting from super class to subclass
...signment Dog dog = (Dog) animal; does not generate a compilation error, but at runtime it generates a ClassCastException . Why can't the compiler detect this error?
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Lost httpd.conf file located apache [closed]
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How to debug PDO database queries?
Before moving to PDO, I created SQL queries in PHP by concatenating strings. If I got database syntax error, I could just echo the final SQL query string, try it myself on the database, and tweak it until I fixed the error, then put that back into the code.
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Android OnClickListener - identify a button
I have the activity:
11 Answers
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Are std::vector elements guaranteed to be contiguous?
My question is simple: are std::vector elements guaranteed to be contiguous? In order word, can I use the pointer to the first element of a std::vector as a C-array?
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How to handle button clicks using the XML onClick within Fragments
Pre-Honeycomb (Android 3), each Activity was registered to handle button clicks via the onClick tag in a Layout's XML:
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How to get the number of characters in a std::string?
How should I get the number of characters in a string in C++?
12 Answers
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How to list active / open connections in Oracle?
Is there any hidden table, system variable or something to show active connections in a given moment?
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Python: Tuples/dictionaries as keys, select, sort
Suppose I have quantities of fruits of different colors, e.g., 24 blue bananas, 12 green apples, 0 blue strawberries and so on.
I'd like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
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Why does datetime.datetime.utcnow() not contain timezone information?
...s this datetime not have any timezone info given that it is explicitly a UTC datetime ?
9 Answers
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