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Is null an Object?
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If null were an Object, it would support the methods of java.lang.Object such as equals(). However, this is not the case - any method invocation on a null results in a NullPointerException.
And this is what the Java Language Specification has to say on this top...
When should the xlsm or xlsb formats be used?
Since Excel 2007, Microsoft has split the classical .xls format to several formats (in particular, .xlsx , .xlsm , .xlsb ). I've got no problem to understand the use and purpose of .xlsx format but I am still wondering whether we should use a .xlsm or a .xlsb format when creating a file c...
Android: What is better - multiple activities or switching views manually?
I have developed some apps for Android, and this questions stays always:
7 Answers
7
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Remove multiple whitespaces
...,$row['message']);
You are using \s\s+ which means whitespace(space, tab or newline) followed by one or more whitespace. Which effectively means replace two or more whitespace with a single space.
What you want is replace one or more whitespace with single whitespace, so you can use the pattern ...
How do I rotate the Android emulator display? [duplicate]
How can I rotate the Android emulator display to see it in landscape mode?
23 Answers
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Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
...ypes:
one type of cheese
one type of meat
one type of vegetable
So we order two pizzas and choose the following toppings:
Pizza Topping Topping Type
-------- ---------- -------------
1 mozzarella cheese
1 pepperoni meat
1 olives vegetable
2 mozzarell...
How to change default timezone for Active Record in Rails?
...this answer because all others seem to be incomplete.
config.active_record.default_timezone determines whether to use Time.local (if set to :local) or Time.utc (if set to :utc) when pulling dates and times from the database. The default is :utc.
http://guides.rubyonrails.org/configuring.html
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Difference between Arrays.asList(array) and new ArrayList(Arrays.asList(array))
...and creates a wrapper that implements List<Integer>, which makes the original array available as a list. Nothing is copied and all, only a single wrapper object is created. Operations on the list wrapper are propagated to the original array. This means that if you shuffle the list wrapper, the...
How can I add new keys to a dictionary?
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@hegash the d[key]=val syntax as it is shorter and can handle any object as key (as long it is hashable), and only sets one value, whereas the .update(key1=val1, key2=val2) is nicer if you want to set multiple values at the same time, as long as the keys are strings...
Split string with multiple delimiters in Python [duplicate]
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Luckily, Python has this built-in :)
import re
re.split('; |, ',str)
Update:Following your comment:
>>> a='Beautiful, is; better*than\nugly'
>>> import re
>>> re.split('; |, |\*|\n',a)
['Beautiful', 'is', 'better', 'than', 'ugly']
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