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What is the easiest/best/most correct way to iterate through the characters of a string in Java?
StringTokenizer ? Convert the String to a char[] and iterate over that? Something else?
15 Answers
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Fastest way to count exact number of rows in a very large table?
...of scope
Notes:
COUNT(1) = COUNT(*) = COUNT(PrimaryKey) just in case
Edit:
SQL Server example (1.4 billion rows, 12 columns)
SELECT COUNT(*) FROM MyBigtable WITH (NOLOCK)
-- NOLOCK here is for me only to let me test for this answer: no more, no less
1 runs, 5:46 minutes, count = 1,401,659,70...
Passing multiple error classes to ruby's rescue clause in a DRY fashion
...
You can use an array with the splat operator *.
EXCEPTIONS = [FooException, BarException]
begin
a = rand
if a > 0.5
raise FooException
else
raise BarException
end
rescue *EXCEPTIONS
puts "rescued!"
end
If you are going to ...
Check if array is empty or null
...k if an array is empty or null in jQuery. I tried array.length === 0 but it didn't work. It did not throw any error either.
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Consequences of using graft in Mercurial
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When you update to D and graft F::J, Mercurial runs a number of merges. It will start with this merge:
M = three_way_merge(local=D, other=F, base=E)
If we write +d for the delta between the states C and D, then we start with:
+d +e +f
---- C ---- D ---- E ---- F ----
Turn th...
Mongoose indexing in production code
...x calls will simply see that the index already exists and then return. So it only has an effect on performance when you're first creating the index, and at that time the collections are often empty so creating an index would be quick anyway.
My suggestion is to leave autoIndex enabled unless you h...
Django dynamic model fields
... some users can define their own data fields (via the admin) to collect additional data in forms and report on the data. The latter bit makes JSONField not a great option, so instead I have the following solution:
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Flask vs webapp2 for Google App Engine
...y considering two frameworks: Flask and webapp2 . I'm rather satisfied with built-in webapp framework that I've used for my previous App Engine application, so I think webapp2 will be even better and I won't have any problems with it.
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Why is Java's boolean primitive size not defined?
The Java Virtual Machine Specification says that there is limited support for boolean primitive types.
7 Answers
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Defining an array of anonymous objects in CoffeeScript
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you can't:
this is some tricks:
items:[
(name:"value1")
(name:"value2")
]
another
items:[
true && name:"value1"
true && name:"value2"
]
this is the best:
items:[
{name:"value1"}
{name:"value2"}
]
...