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Java generics type erasure: when and what happens?
...tring>. But objects don't just appear from nowhere. They are created locally, passed in as a method invocation argument, returned as the return value from a method call, or read from a field of some object... In all these cases you CAN know at runtime what the generic type is, either implicitly ...
Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSER...
Get selected option from select element
...ted elements use
$("select option:selected").length
To Get the value of all selected elements use
var str = "";
$("select option:selected").each(function () {
str += $(this).text() + " ";
});
share
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JavaScript validation for empty input field
I have this input field
<input name="question"/> I want to call IsEmpty function when submit clicking submit button.
...
Adding a directory to the PATH environment variable in Windows
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Hmm, no, it truly really only modifies the registry. Ought to be a bit obvious from doing this in a Control Panel dialog instead of, say, the command prompt with the PATH command. You can observe what it does easily with SysInternals' Process ...
Unable to load DLL 'SQLite.Interop.dll'
Periodically I am getting the following exception:
41 Answers
41
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Does “untyped” also mean “dynamically typed” in the academic CS world?
...theory". Programming language theory is based on these foundations. And in all these mathematical contexts, "type" has a particular, well-established meaning.
The terminology "dynamic typing" was invented much later -- and it is a contradiction in terms in the face of the common mathematical use of...
Long-held, incorrect programming assumptions [closed]
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For a long time I assumed that everyone else had this super-mastery of all programming concepts (design patterns, the latest new language, computational complexity, lambda expressions, you name it).
Reading blogs, Stack Overflow and programming books always seemed to make me feel that I was beh...
How does autowiring work in Spring?
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First, and most important - all Spring beans are managed - they "live" inside a container, called "application context".
Second, each application has an entry point to that context. Web applications have a Servlet, JSF uses a el-resolver, etc. Also, th...
Android Whatsapp/Chat Examples [closed]
...e to understand how chat applications are programmed.
There is a website called Scringo. These awesome people provide their own SDK which you can integrate in your existing application to exploit cool features like radaring, chatting, feedback, etc. So if you are looking to integrate chat in applic...