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What is the difference between Strategy pattern and Dependency Injection?
Strategy pattern and Dependency Injection both allow us to set / inject objects at run time. What is the difference between Strategy pattern and Dependency Injection?
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Is there a way to create your own html tag in HTML5?
...? and the HTML5 spec).
Let's assume you want to use a custom tag element called <stack>. Here's what you should do...
STEP 1
Normalize its attributes in your CSS Stylesheet (think css reset) -
Example:
stack{display:block;margin:0;padding:0;border:0; ... }
STEP 2
To get it to work in ...
MongoDB: How to query for records where field is null or not set?
...ount({sent_at: {$exists: false}})
If its there and null, or not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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What is Android keystore file, and what is it used for?
... going to use "push data" in your app!
– KapteinMarshall
Sep 4 '13 at 9:43
Is Keystore machine specific ? Or we can u...
How to make/get a multi size .ico file? [closed]
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I had all the images already, delivered by the artist for mac. All I had to do was open one of them in Gimp, and the choose "Open as layers.." on the remaining ones. All layers are automatically created in the correct size, export ...
Mysql error 1452 - Cannot add or update a child row: a foreign key constraint fails
...d FROM sourcecodes) should help to get rid of those IDs. Or if null is not allowed in sourcecode_id, then remove those rows or add those missing values to the sourcecodes table.
– naXa
Feb 23 '16 at 14:28
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How can I check if a single character appears in a string?
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But there's always a loop behind that call because you can't find a symbol otherwise.
– vava
Feb 3 '09 at 6:25
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How accurately should I store latitude and longitude?
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Actually, equator is best case. One latitude and one longitude degree are the same size at the equator (69 miles), but one degree of longitude shrinks to zero as it approaches either of the poles. Here's a very nice explanation: ...
Java Singleton and Synchronization
...e loaded when it is needed. That means that the first time getInstance is called, InstanceHolder will be loaded and instance will be created, and since this is controlled by ClassLoaders, no additional synchronization is necessary.
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Is there a way to measure how sorted a list is?
...er according to some ordering < on the set of T's.
From Wikipedia:
Formally, let A(1), A(2), ..., A(n) be a sequence of n numbers.If i < j and A(i) > A(j), then the pair (i,j) is called an inversion of A.
The inversion number of a sequence is one common measure of its sortedness.Formally, ...