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Deleting an object in java?
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You should remove the references to it by assigning null or leaving the block where it was declared. After that, it will be automatically deleted by the garbage collector (not immediately, but eventually).
Example 1:
Object a = new Object();
a = null; // afte...
python max function using 'key' and lambda expression
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lambda is an anonymous function, it is equivalent to:
def func(p):
return p.totalScore
Now max becomes:
max(players, key=func)
But as def statements are compound statements they can't be used where an expression is required, that's why sometime...
What is an efficient way to implement a singleton pattern in Java? [closed]
...ngleton
public enum Elvis {
INSTANCE;
private final String[] favoriteSongs =
{ "Hound Dog", "Heartbreak Hotel" };
public void printFavorites() {
System.out.println(Arrays.toString(favoriteSongs));
}
}
Edit: An online portion of "Effective Java" says:
"This ap...
What is size_t in C?
I am getting confused with size_t in C. I know that it is returned by the sizeof operator. But what exactly is it? Is it a data type?
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Interfaces — What's the point?
The reason for interfaces truly eludes me. From what I understand, it is kind of a work around for the non-existent multi-inheritance which doesn't exist in C# (or so I was told).
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Ajax, back button and DOM updates
If javascript modifies DOM in page A, user navigates to page B and then hits back button to get back to the page A. All modifications to DOM of page A are lost and user is presented with version that was originally retrieved from the server.
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Enterprise app deployment doesn't work on iOS 7.1
We distribute apps via an Enterprise account, using an itms-services:// URL. This has always worked fine, but after installing the iOS 7.1 beta on our iPad it refuses to install. Instead we just get the generic Cannot connect to example.com message that iOS unhelpfully displays when there is any...
querySelector search immediate children
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Though it's not a full answer, you should keep an eye on the W3C Selector API v.2 which is already available in most browser, both desktop and mobile, except IE (Edge seems to support): see full support list.
function(elem) {
ret...
Repairing Postgresql after upgrading to OSX 10.7 Lion
...n completely borked when trying to connect to the psql server. When I do it from the command line using
15 Answers
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How can I set focus on an element in an HTML form using JavaScript?
I have a web form with a text box in it. How do I go about setting focus to the text box by default?
9 Answers
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