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nil detection in Go
... memory is given a default initialization. Each element of such a value is set to the zero value for its type: false for booleans, 0 for integers, 0.0 for floats, "" for strings, and nil for pointers, functions, interfaces, slices, channels, and maps. This initialization is done recursively, so for ...
SQLite table constraint - unique on multiple columns
... cheese'),
('Alice', 'Some other title')
ON CONFLICT(a) DO UPDATE SET b=excluded.b;
CREATE TABLE IF NOT EXISTS t2 (id INTEGER PRIMARY KEY, a TEXT UNIQUE, b TEXT, UNIQUE(a) ON CONFLICT REPLACE);
INSERT INTO t2 (a, b) VALUES
('Alice', 'Some title'),
('Bob', 'Palindromic guy'),
('C...
How to manually set an authenticated user in Spring Security / SpringMVC
...new UsernamePasswordAuthenticationToken(username, password);
token.setDetails(new WebAuthenticationDetails(request));
Authentication authentication = this.authenticationProvider.authenticate(token);
logger.debug("Logging in with [{}]", authentication.getPrincipal());
...
How to find and turn on USB debugging mode on Nexus 4
In settings on my Nexus 4 device there isn't any "USB debugging options" item. How do I find and turn on USB debugging mode on Nexus 4?
...
What's is the difference between train, validation and test set, in neural networks?
...
The training and validation sets are used during training.
for each epoch
for each training data instance
propagate error through the network
adjust the weights
calculate the accuracy over training data
for each validati...
How to create a file with a given size in Linux?
...ed as far as the file system sees it. Also fallocate nor truncate will not set the contents of the file to a specified value like dd, instead the contents of a file allocated with fallocate or truncate may be any trash value that existed in the allocated units during creation and this behavior may o...
Checking if an Android application is running in the background
...s, but you also don't have to modify every Activity in your application to set/unset something in onResumed()/onPaused(). It's just a few lines of code that's self contained, and it works throughout your whole application. Plus, there are no funky permissions required either.
MyLifecycleHandler.jav...
Disabling Chrome Autofill
...".fake-autofill-fields").show();
// some DOM manipulation/ajax here
window.setTimeout(function () {
$(".fake-autofill-fields").hide();
}, 1);
Update July 2018
My solution no longer works so well since Chrome's anti-usability experts have been hard at work. But they've thrown us a bone in the form...
DataContractSerializer doesn't call my constructor?
...serves no purpose at all. The no-argument constructor should be allowed to setup state whether or not it is about to be deserialized. If they wanted a specific optimization, there is the StreamingContext constructor.
– Mranz
Dec 5 '11 at 16:15
...
Best way to create an empty map in Java
...t;emptyMap(); // or guava ImmutableMap.of()
}
}
}
Similarly for sets:
class SetUtils {
static <T> Set<T> nullToEmpty(Set<T> set) {
if (set != null) {
return set;
} else {
return Collections.<T>emptySet();
}
}
}
and lists:
class Lis...