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in a “using” block is a SqlConnection closed on return or exception?
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Using generates a try / finally around the object being allocated and calls Dispose() for you.
It saves you the hassle of manually creating the try / finally block and calling Dispose()
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Is there a destructor for Java?
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Nope, no destructors here. The reason is that all Java objects are heap allocated and garbage collected. Without explicit deallocation (i.e. C++'s delete operator) there is no sensible way to implement real destructors.
Java does support finalizers, but they are meant to be used only as a safegu...
How to read the content of a file to a string in C?
... 0, SEEK_END);
length = ftell (f);
fseek (f, 0, SEEK_SET);
buffer = malloc (length);
if (buffer)
{
fread (buffer, 1, length, f);
}
fclose (f);
}
if (buffer)
{
// start to process your data / extract strings here...
}
...
How do I base64 encode (decode) in C?
... *output_length = 4 * ((input_length + 2) / 3);
char *encoded_data = malloc(*output_length);
if (encoded_data == NULL) return NULL;
for (int i = 0, j = 0; i < input_length;) {
uint32_t octet_a = i < input_length ? (unsigned char)data[i++] : 0;
uint32_t octet_b = ...
“implements Runnable” vs “extends Thread” in Java
...reate separate instance for every thread access. Hence different memory is allocated for every class instances and each has separate counter, the value remains same, which means no increment will happen because none of the object reference is same.
When to use Runnable?
Use Runnable interface when y...
C++ Lock-free Hazard Pointer（冒险指针） - C/C++ - 清泛网 - 专注C/C++及内核技术
...re(const std::atomic<T *> &target) {
auto pointer = HazardPointer<T>::Alloc();
do {
pointer->target_ = target.load(std::memory_order_acquire);
} while (pointer->target_.load(std::memory_order_acquire) !=
target.load(std::memory_order_acquire));
return Holde...
Base64 Decoding in iOS 7+
...g(@"%@", base64String); // Zm9v
Decoding
NSData *decodedData = [[NSData alloc] initWithBase64EncodedString:base64String options:0];
NSString *decodedString = [[NSString alloc] initWithData:decodedData encoding:NSUTF8StringEncoding];
NSLog(@"%@", decodedString); // foo
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Array include any value from another array?
...de? may be faster as shown by Lee Jarvis' answer -- probably because & allocates a new Array while another solution does not and works as a simple nested loop to return a boolean.
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improv...
Do you (really) write exception safe code? [closed]
...tor's swap, the vector's swap won't throw if the two vectors have the same allocator (i.e., the normal case), but will make copies if they have different allocators. And thus, I assume it could throw in this last case.
So, the original text still holds: Don't ever write a throwing swap, but nobar's ...
Make a program run slowly
...ll not slow down the execution speed per se, but will make Linux scheduler allocate less (and possibly shorter) execution time frames, preempt more often, etc. See Process Scheduling (Chapter 10) of Understanding the Linux Kernel for more details on scheduling.
You may want to increase the timer int...