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How to sort a HashSet?
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Add all your objects to the TreeSet, you will get a sorted Set. Below is a raw example.
HashSet myHashSet = new HashSet();
myHashSet.add(1);
myHashSet.add(23);
myHashSet.add(45);
myHashSet.add(12);
TreeSet myTreeSet = new TreeS...
Java Reflection Performance
Does creating an object using reflection rather than calling the class constructor result in any significant performance differences?
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What's the difference between the various methods to get a Context?
...ion about contexts as well:
In a regular Android application, you
usually have two kinds of Context,
Activity and Application.
Reading the article a little bit further tells about the difference between the two and when you might want to consider using the application Context (Activity.get...
Android add placeholder text to EditText
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Thanks! I didn't know what they call it in android, I just know that on iOS it's called placeholder.
– Mona
Nov 22 '11 at 4:24
40
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How do I query between two dates using MySQL?
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Personally, I find the term 'from' and 'to' a sneaky way to remember the order in which the query should be written.
– KeaganFouche
Jan 21 '19 at 22:04
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Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
...cross-use" %lf with float or %f with double.
But there's no reason to actually do it in practice. Don't use %f to printf arguments of type double. It is a widespread habit born back in C89/90 times, but it is a bad habit. Use %lf in printf for double and keep %f reserved for float arguments.
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CSS does the width include the padding?
...width: 10em; padding: 2em; border: 1em; }
would be 10em wide.
In contrast, all standards-fearing browsers default to the "content-box" box model. In this model, the width of an element does not include padding or borders. For example:
#foo { width: 10em; padding: 2em; border: 1em; }
will actually be...
How to set delay in android?
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This solution explained all the questions that I had with handlers at some lines of code.
– Sierisimo
May 19 '15 at 17:55
47
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How persistent is localStorage?
I'm depending heavily on localStorage for a plugin I'm writing. All the user settings are stored in it. Some settings require the user the write regex'es and they would be sad if their regex rules are gone at some point.
So now I am wondering just how persistent the localStorage is.
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How to store arrays in MySQL?
...raberry"
2 | "banana"
2 | "apple"
When you want to retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
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