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Why doesn't “System.out.println” work in Android?
I want to print something in console, so that I can debug it. But for some reason, nothing prints in my Android application.
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javax vs java package
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I think it's a historical thing - if a package is introduced as an addition to an existing JRE, it comes in as javax. If it's first introduced as part of a JRE (like NIO was, I believe) then it comes in as java. Not sure why the new ...
What data type to use for hashed password field and what length?
I'm not sure how password hashing works (will be implementing it later), but need to create database schema now.
10 Answers...
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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What is the difference between visibility:hidden and display:none?
The CSS rules visibility:hidden and display:none both result in the element not being visible. Are these synonyms?
18 A...
What is the difference between a process and a thread?
...ions that make threads efficient).
Erlang uses the term "process" because it does not expose a shared-memory multiprogramming model. Calling them "threads" would imply that they have shared memory.
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Is it possible to perform a 'grep search' in all the branches of a Git project?
Is it possible to run git grep inside all the branches of a Git control sourced project? Or is there another command to run?
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How can I search Git branches for a file or directory?
In Git, how could I search for a file or directory by path across a number of branches?
6 Answers
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The 'json' native gem requires installed build tools
...running them and before the last attempt to install the gem that wants devkit present?
Also, be sure you are using the right devkit installer for your version of Ruby. The documentation at devkit wiki page has a requirements note saying:
For RubyInstaller versions 1.8.7, 1.9.2, and 1.9.3 use ...
Format timedelta to string
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You can just convert the timedelta to a string with str(). Here's an example:
import datetime
start = datetime.datetime(2009,2,10,14,00)
end = datetime.datetime(2009,2,10,16,00)
delta = end-start
print(str(delta))
# prints 2:00:00
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