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How to add elements of a Java8 stream into an existing List
... to add to an existing collection using forEachOrdered(). This is a useful and effective technique for mutating existing collections. My answer addresses why you shouldn't use a Collector to mutate an existing collection.
The short answer is no, at least, not in general, you shouldn't use a Collect...
Is it safe to check floating point values for equality to 0?
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It is safe to expect that the comparison will return true if and only if the double variable has a value of exactly 0.0 (which in your original code snippet is, of course, the case). This is consistent with the semantics of the == operator. a == b means "a is equal to b".
It is not sa...
Connect Java to a MySQL database
...(DataSource) context.lookup("java:comp/env/jdbc/myDB");
or instantiating and configuring one from your database driver directly:
MysqlDataSource dataSource = new MysqlDataSource();
dataSource.setUser("scott");
dataSource.setPassword("tiger");
dataSource.setServerName("myDBHost.example.org");
an...
What is an “unwrapped value” in Swift?
I'm learning Swift for iOS 8 / OSX 10.10 by following this tutorial , and the term " unwrapped value " is used several times, as in this paragraph (under Objects and Class ):
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MySQL Great Circle Distance (Haversine formula)
I've got a working PHP script that gets Longitude and Latitude values and then inputs them into a MySQL query. I'd like to make it solely MySQL. Here's my current PHP Code:
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What do people find difficult about C pointers? [closed]
...ve some pretty fundemental issues when getting their heads around pointers and pointer arithmetic.
29 Answers
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Conditional formatting based on another cell's value
...low, it actually means "B{current_row}", so for C5 it's B5, for C6 it's B6 and so on. Unless you specify $B$5 - then you refer to one specific cell.
This is supported in Google Sheets as of 2015:
https://support.google.com/drive/answer/78413#formulas
In your case, you will need to set conditiona...
What are the differences between “generic” types in C++ and Java?
Java has generics and C++ provides a very strong programming model with template s.
So then, what is the difference between C++ and Java generics?
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Can you help me understand this? “Common REST Mistakes: Sessions are irrelevant”
Disclaimer: I'm new to the REST school of thought, and I'm trying to wrap my mind around it.
6 Answers
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How many database indexes is too many?
...nds on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since they all ...