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Convert ArrayList to String[] array [duplicate]
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According to Joshua Bloch in Effective Java, preallocating the array harms performance. Provide a zero-length array instead. stockList.toArray(new String[0])
– Crashh
Mar 10 '18 at 3:20
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What are file descriptors, explained in simple terms?
....h) opened by default on behalf of shell when the program starts.
FD's are allocated in the sequential order, meaning the lowest possible unallocated integer value.
FD's for a particular process can be seen in /proc/$pid/fd (on Unix based systems).
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How to use PHP OPCache?
...econds) to check file timestamps for changes to the shared
;memory storage allocation.
opcache.revalidate_freq=60
;If enabled, a fast shutdown sequence is used for the accelerated code
;The fast shutdown sequence doesn't free each allocated block, but lets
;the Zend Engine Memory Manager do the wor...
Creating a blurring overlay view
...tStyleDark];
UIVisualEffectView *blurEffectView = [[UIVisualEffectView alloc] initWithEffect:blurEffect];
//always fill the view
blurEffectView.frame = self.view.bounds;
blurEffectView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
[self.v...
Placeholder in UITextView
...at const UI_PLACEHOLDER_TEXT_CHANGED_ANIMATION_DURATION = 0.25;
- (void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
#if __has_feature(objc_arc)
#else
[_placeHolderLabel release]; _placeHolderLabel = nil;
[_placeholderColor release]; _placeholderColor = nil;
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Why is @autoreleasepool still needed with ARC?
...now there's a ton of objects ready to be cleared out, you have a loop that allocates a bunch of temp objects, so you "know" (or Instruments might tell you :) that adding a release pool around the loop would be a good idea.
– Graham Perks
Jan 31 '12 at 21:28
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When NOT to use yield (return) [duplicate]
...e O(n) in stack space. It is O(h) in heap space because each enumerator is allocated on the heap. (On implementations of C# I'm aware of; a conforming implementation might have other stack or heap space characteristics.)
But iterating a tree can be O(n) in time and O(1) in stack space. You can wr...
Read stream twice
... = new ByteArrayOutputStream(); // as ByteArrayOutputStream to dynamically allocate internal bytes array instead of allocating possibly large buffer (if maxBytesToRead is large)
// NOTE: below reading byte by byte instead of "int bytesRead = is.read(firstBytes, 0, maxBytesOfResponseToLog);"
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iOS 7 TextKit - How to insert images inline with text?
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NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:@"like after"];
NSTextAttachment *textAttachment = [[NSTextAttachment alloc] init];
textAttachment.image = [UIImage imageNamed:@"whatever.png"];
NSAttributedString *attrStringWithImage = [NSAttributedS...
“static const” vs “#define” vs “enum”
...ll appear in the object code as part of the instructions rather than being allocated storage in the data segment or in heap or on the stack. You'll have some space allocated for the static const int, but the compiler might optimize it away if you don't take an address.
– Jonat...