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What is a difference between
...ecause you can be sure that whatever the actual list contains, it can be upcasted to a Number (after all anything that extends Number is a Number, right?)
However, you are not allowed to put anything into a covariant structure.
myNumst.add(45L); //compiler error
This would not be allowed, because J...
What does (angle brackets) mean in Java?
...ype String, so you can't add any other type to it (try obj.add(1), it will cast an error). Similarly, obj1 is of the Integer type, you can't add any other type to it (try obj1.add("hello"), error will be there).
share
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How to send a stacktrace to log4j?
Say you catch an exception and get the following on the standard output (like, say, the console) if you do a e.printStackTrace() :
...
Is it possible to do start iterating from an element other than the first using foreach?
...DataGridView, try this
foreach (DataGridViewRow row in dataGridView1.Rows.Cast<DataGridViewRow().Skip(3))
If you want to copy contents of one DataGridView to another skipping rows, try this,
foreach (DataGridViewRow row in dataGridView1.Rows.Cast<DataGridViewRow>().Skip(3))
{
foreac...
How to upload a file in Django? [closed]
...xample about this. I spent over 2 hours to dig up all the pieces to understand how this works. With that knowledge I implemented a project that makes possible to upload files and show them as list. To download source for the project, visit https://github.com/axelpale/minimal-django-file-upload-exam...
How to use ssh agent forwarding with “vagrant ssh”?
...onfig.ssh.forward_agent to TRUE in the Vagrantfile, then rebooted the VM, and tried using:
9 Answers
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python location on mac osx
...if the previous owner of the laptop has installed macpython using macport. And I remembered that osx has an builtin version of python. I tried using type -a python and the result returned
...
socket.shutdown vs socket.close
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Calling close and shutdown have two different effects on the underlying socket.
The first thing to point out is that the socket is a resource in the underlying OS and multiple processes can have a handle for the same underlying socket.
W...
Using multiple let-as within a if-statement in Swift
...'m unwrapping two values from a dictionary and before using them I have to cast them and test for the right type. This is what I came up with:
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How to place the ~/.composer/vendor/bin directory in your PATH?
I'm on Ubuntu 14.04 and I've been trying all possible methods to install Laravel to no avail. Error messages everything I try. I'm now trying the first method in the quickstart documentation, that is, via Laravel Installer, but it says to "Make sure to place the ~/.composer/vendor/bin directory in...