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Why can't strings be mutable in Java and .NET?
Why is it that they decided to make String immutable in Java and .NET (and some other languages)? Why didn't they make it mutable?
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How to read contacts on Android 2.0
I'm working on Android 2.0 and am trying to receive a list of all contacts.
9 Answers
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static constructors in C++? I need to initialize private static objects
...tatic constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables are read only and only need to be set once) and since it's a function of the class it can access its private members. I could add code ...
LINQ to SQL Left Outer Join
...re-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
select new {...
Why does InetAddress.isReachable return false, when I can ping the IP address?
...ll to the bottom to see my alternative for simply testing if you're online and capable of resolving external hosts (i.e. google.com) ... Which generally seems to work on *NIX machines.
The issue
There is alot of chatter about this :
Here are other, similar questions :
Detect internet Conne...
Unable to run app in Simulator: Xcode beta 6 iOS 8
I am unable to launch my app on simulator using Xcode 6 beta and iPhone 5s simulator.
First I am getting an error message from Simulator
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Best way to remove from NSMutableArray while iterating?
In Cocoa, if I want to loop through an NSMutableArray and remove multiple objects that fit a certain criteria, what's the best way to do this without restarting the loop each time I remove an object?
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Why use prefixes on member variables in C++ classes
...y specific case, I found the _L happened to be reserved by Visual C++ 2005 and the clash created some unexpected results.
I am on the fence about how useful it is to mark up local variables.
Here is a link about which identifiers are reserved:
What are the rules about using an underscore in a C++ ...
Java: how to initialize String[]?
...here is no memory allocated for the String elements, but only a reference handle to errorSoon, and will throw an error when you try to initialize a variable at any index.
As a side note, you could also initialize the String array inside braces, { } as so,
String[] errorSoon = {"Hello", "World"};
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Delete column from SQLite table
...xample, suppose you have a table named "t1" with columns names
"a", "b", and "c" and that you want to delete column "c" from this
table. The following steps illustrate how this could be done:
BEGIN TRANSACTION;
CREATE TEMPORARY TABLE t1_backup(a,b);
INSERT INTO t1_backup SELECT a,b FROM t1;
DRO...