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Grab a segment of an array in Java without creating a new array on heap
...on't know of a way to do this directly with arrays without additional heap allocation, but the other answers using a sub-list wrapper have additional allocation for the wrapper only – but not the array – which would be useful in the case of a large array.
That said, if one is looking for bre...
How to make MySQL handle UTF-8 properly
...taking extra storage when most text is ASCII. Although char strings are preallocated, varchar strings are not -- see the last few lines on this documentation page. For example, char(10) will be pessimistically reserve 40 bytes under utf8mb4, but varchar(10) will allocate bytes in keeping with the v...
Is int[] a reference type or a value type?
...bject. This means that
all arrays are always reference types
which are allocated on the managed
heap, and your app's variable contains
a reference to the array and not the
array itself.
https://msdn.microsoft.com/en-us/library/bb985948.aspx
...
Returning a C string from a function
...9+1 (=10!) bytes. This is important to know when you finally get around to allocating strings dynamically.
So, without this 'terminating zero', you don't have a string. You have an array of characters (also called a buffer) hanging around in memory.
Longevity of data:
The use of the function this...
In C#, why is String a reference type that behaves like a value type?
...e (in all implementations of the CLR as of yet) stored on the stack. Stack allocating strings would break all sorts of things: the stack is only 1MB for 32-bit and 4MB for 64-bit, you'd have to box each string, incurring a copy penalty, you couldn't intern strings, and memory usage would balloon, et...
How to use NSJSONSerialization
..."; // The Openweathermap JSON responder
NSURL *url = [[NSURL alloc]initWithString:urlString];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
NSURLResponse *response;
NSData *GETReply = [NSURLConnection sendSynchronousRequest:request returningResponse:&resp...
What uses are there for “placement new”?
...
Placement new allows you to construct an object in memory that's already allocated.
You may want to do this for optimization when you need to construct multiple instances of an object, and it is faster not to re-allocate memory each time you need a new instance. Instead, it might be more efficien...
What is the difference between class and instance methods?
...hen be used like so:
[MyClass aClassMethod];
MyClass *object = [[MyClass alloc] init];
[object anInstanceMethod];
Some real world examples of class methods are the convenience methods on many Foundation classes like NSString's +stringWithFormat: or NSArray's +arrayWithArray:. An instance method...
strdup() - what does it do in C?
...e as the following code:
char *strdup(const char *src) {
char *dst = malloc(strlen (src) + 1); // Space for length plus nul
if (dst == NULL) return NULL; // No memory
strcpy(dst, src); // Copy the characters
return dst; // Re...
Running the new Intel emulator for Android
...developer It really works !!! When you installed HAXM how much RAM did you allocate ? I allocated 512 MB and its blazingly fast !
– GoodSp33d
May 3 '13 at 4:28
...