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Servlet returns “HTTP Status 404 The requested resource (/servlet) is not available”
...oblems. Packageless servlets work only in specific Tomcat+JDK combinations and this should never be relied upon.
In case of a "plain" IDE project, the class needs to be placed in its package structure inside "Java Resources" folder and thus not "WebContent", this is for web files such as JSP. Belo...
Why does PHP 5.2+ disallow abstract static class methods?
After enabling strict warnings in PHP 5.2, I saw a load of strict standards warnings from a project that was originally written without strict warnings:
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Is there any kind of hash code function in JavaScript?
...d, alternatively, maintain an array which indexes the objects in question, and use its index string as a reference to the object. Something like this:
var ObjectReference = [];
ObjectReference.push(obj);
set['ObjectReference.' + ObjectReference.indexOf(obj)] = true;
Obviously it's a little verbo...
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
Is there a rule-of-thumb for how to best divide data into training and validation sets? Is an even 50/50 split advisable? Or are there clear advantages of having more training data relative to validation data (or vice versa)? Or is this choice pretty much application dependent?
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If strings are immutable in .NET, then why does Substring take O(n) time?
... liked this question so much, I just blogged it. See Strings, immutability and persistence
The short answer is: O(n) is O(1) if n does not grow large. Most people extract tiny substrings from tiny strings, so how the complexity grows asymptotically is completely irrelevant.
The long answer is:
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Why does C++11 not support designated initializer lists as C99? [closed]
... constructor. This is the sort of abstraction C++ promotes.
On the other hand the designated initializers feature is more about exposing and making members easy to access directly in client code. This leads to things like having a person of age 18 (years?) but with height and weight of zero.
In ...
UIActivityViewController crashing on iOS 8 iPads
... Xcode 6 (Beta 6). UIActivityViewController works fine with iPhone devices and simulators but crashes with iPad simulators and devices (iOS 8) with following logs
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Can C++ code be valid in both C++03 and C++11 but do different things?
Is it possible for C++ code to conform to both the C++03 standard and the C++11 standard, but do different things depending on under which standard it is being compiled?
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Difference between “git add -A” and “git add .”
The command git add [--all|-A] appears to be identical to git add . . Is this correct? If not, how do they differ?
11 An...
CSS Selector “(A or B) and C”?
...(.a .b) .c {
/* stuff goes here */
}
You can find more info on it here and here. Currently, most browsers support its initial version :any(), which works the same way, but will be replaced by :matches(). We just have to wait a little more before using this everywhere (I surely will).
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