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How to get the current date and time

...e(); In the words of the Javadocs for the zero-argument constructor: Allocates a Date object and initializes it so that it represents the time at which it was allocated, measured to the nearest millisecond. Make sure you're using java.util.Date and not java.sql.Date -- the latter doesn't hav...
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Declaring variables inside or outside of a loop

...ew string in each iteration of the loop, then you could optimize things by allocating the StringBuilder outside the loop. But still, this is not an advisable practice. If you do it without a very good reason, it is a premature optimization. – Mike Nakis Jan 11 ...
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Calling Objective-C method from C++ member function?

... : self( NULL ) { } MyClassImpl::~MyClassImpl( void ) { [(id)self dealloc]; } void MyClassImpl::init( void ) { self = [[MyObject alloc] init]; } int MyClassImpl::doSomethingWith( void *aParameter ) { return [(id)self doSomethingWith:aParameter]; } void MyClassImpl::logMyMessage...
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.NET XML serialization gotchas? [closed]

...nk characters that won't deserialize properly (because of the extra buffer allocated). http://msdn.microsoft.com/en-us/library/system.io.memorystream.getbuffer(VS.80).aspx share | improve this answ...
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How to take a screenshot programmatically on iOS

...ge*) getGLScreenshot { NSInteger myDataLength = 320 * 480 * 4; // allocate array and read pixels into it. GLubyte *buffer = (GLubyte *) malloc(myDataLength); glReadPixels(0, 0, 320, 480, GL_RGBA, GL_UNSIGNED_BYTE, buffer); // gl renders "upside down" so swap top to bottom into ...
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How to use http.client in Node.js if there is basic authorization

... is deprecated due to security and usability issues. Please use the Buffer.alloc(), Buffer.allocUnsafe(), or Buffer.from() methods instead – Sourabh Mar 22 '19 at 11:11 add a ...
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Remove columns from dataframe where ALL values are NA

...m.time({df1 <- bd[,colSums(is.na(bd) < nrow(bd))]}) # error -- can't allocate vector of size ... system.time({df2 <- bd[, !apply(is.na(bd), 2, all)]}) # error -- can't allocate vector of size ... system.time({df3 <- Filter(function(x)!all(is.na(x)), bd)}) ## user system elapsed ## 0.26...
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How to draw a custom UIView that is just a circle - iPhone app

... could use QuartzCore and do something this -- self.circleView = [[UIView alloc] initWithFrame:CGRectMake(10,20,100,100)]; self.circleView.alpha = 0.5; self.circleView.layer.cornerRadius = 50; // half the width/height self.circleView.backgroundColor = [UIColor blueColor]; ...
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How can I scan barcodes on iOS?

...tWithDevice:self.device error:nil]; self.session = [[AVCaptureSession alloc] init]; self.output = [[AVCaptureMetadataOutput alloc] init]; [self.session addOutput:self.output]; [self.session addInput:self.input]; [self.output setMetadataObjectsDelegate:self queue:dispatch_get_m...
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Increase heap size in Java

... It is possible to increase heap size allocated by the JVM by using command line options Here we have 3 options -Xms<size> set initial Java heap size -Xmx<size> set maximum Java heap size -Xss<size> set java thread stack si...