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What is the “reactor” in Maven?
...r and am confused by its terminology usage. I've read that a multi-module is a reactor, that you can manipulate the maven reactor and that the reactor is a plugin. What exactly is the reactor?
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Why does Git treat this text file as a binary file?
I wonder why git tells me this:?
14 Answers
14
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How to convert Linux cron jobs to “the Amazon way”?
...d (Amazon EC2 machines). It's going great so far but the way we do crons is sub-optimal. I have a Amazon-specific question about how to best manage cron jobs in the cloud using "the Amazon way".
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Converting JSON String to Dictionary Not List
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Your JSON is an array with a single object inside, so when you read it in you get a list with a dictionary inside. You can access your dictionary by accessing item 0 in the list, as shown below:
json1_data = json.loads(json1_str)[0]
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Is there a read-only generic dictionary available in .NET?
...ad only property. How do I prevent consumers from changing my data? If this were an IList I could simply return it AsReadOnly . Is there something similar I can do with a dictionary?
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System.currentTimeMillis() vs. new Date() vs. Calendar.getInstance().getTime()
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System.currentTimeMillis() is obviously the most efficient since it does not even create an object, but new Date() is really just a thin wrapper about a long, so it is not far behind. Calendar, on the other hand, is relatively slow and very comple...
CHECK constraint in MySQL is not working
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MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
The CHECK clau...
What does the “>” (greater-than sign) CSS selector mean?
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> is the child combinator, sometimes mistakenly called the direct descendant combinator.1
That means the selector div > p.some_class only selects paragraphs of .some_class that are nested directly inside a div, and not any p...
Transposing a 2D-array in JavaScript
... an array, in order, and constructs a new array from the results. callback is invoked only for indexes of the array which have assigned values; it is not invoked for indexes which have been deleted or which have never been assigned values.
callback is invoked with three arguments: the value of ...
When do you use map vs flatMap in RxJava?
...ne event to another.
flatMap transform one event to zero or more event. (this is taken from IntroToRx)
As you want to transform your json to an object, using map should be enough.
Dealing with the FileNotFoundException is another problem (using map or flatmap wouldn't solve this issue).
To solve ...