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JPA getSingleResult() or null
... doesn't exist or update it if it does. To enable this, I have to findByIdAndForeignKey , if it returned null insert if not then update. The problem is how do I check if it exists? So I tried getSingleResult . But it throws an exception if the
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How to copy text programmatically in my Android app?
I'm building an Android app and I want to copy the text value of an EditText widget. It's possible for the user to press Menu+A then Menu+C to copy the value, but how would I do this programmatically?
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Unexpected Caching of AJAX results in IE8
...n:
$.ajaxSetup({
cache: false
});
which will cause jQuery to add a random value to the request query string, thereby preventing IE from caching the response.
Note that if you have other Ajax calls going on where you do want caching, this will disable it for those too. In that case, switch to...
How do lexical closures work?
.... This is exactly the problem, though - in this environment, i is mutated, and the closures all refer to the same i.
Here is the best solution I can come up with - create a function creater and invoke that instead. This will force different environments for each of the functions created, with a dif...
Ruby on Rails generates model field:type - what are the options for field:type?
I'm trying to generate a new model and forget the syntax for referencing another model's ID. I'd look it up myself, but I haven't figured out, among all my Ruby on Rails documentation links, how to find the definitive source.
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How to convert a char to a String?
I have a char and I need a String . How do I convert from one to the other?
12 Answers
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Responsive css background images
I have a website (g-floors.eu) and I want to make the background (in css I have defined a bg-image for the content) also responsive. Unfortunately I really don't have any idea on how to do this except for one thing that I can think of but it's quite a workaround. Creating multiple images and then us...
Are Mutexes needed in javascript?
...en this link: Implementing Mutual Exclusion in JavaScript .
On the other hand, I have read that there are no threads in javascript, but what exactly does that mean?
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What's an appropriate HTTP status code to return by a REST API service for a validation failure?
...ad Request). For instance if the URI is supposed to have an ISO-8601 date and you find that it's in the wrong format or refers to February 31st, then you would return an HTTP 400. Ditto if you expect well-formed XML in an entity body and it fails to parse.
(1/2016): Over the last five years WebDA...
Display a float with two decimal places in Python
...oat arguments (generally integers or decimals with one significant digit), and I need to output the values in a string with two decimal places (5 -> 5.00, 5.5 -> 5.50, etc). How can I do this in Python?
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