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How do I call one constructor from another in Java?
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Entity Attribute Value Database vs. strict Relational Model Ecommerce
...ponents
Con: complex code required to validate simple data types
Con: much more complex SQL for simple
reports
Con: complex reports can become almost
impossible
Con: poor performance for large data sets
Option 2, Modelling each entity separately:
Con: more time required to gather
requirements an...
How to generate random SHA1 hash to use as ID in node.js?
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243,583,606,221,817,150,598,111,409x more entropy
I'd recommend using crypto.randomBytes. It's not sha1, but for id purposes, it's quicker, and just as "random".
var id = crypto.randomBytes(20).toString('hex');
//=> f26d60305dae929ef8640a75e70dd78ab809cfe9
...
What does “S3 methods” mean in R?
...ly, the user of your newly created funky model fitting package, it is much more convenient to be able to type predict(myfit, type="class") than predict.mykindoffit(myfit, type="class").
There is quite a bit more to it, but this should get you started. There are quite a few disadvantages to this way...
Test whether string is a valid integer
... a literal "-"
The ? means "0 or 1 of the preceding (-)"
The + means "1 or more of the preceding ([0-9])"
The $ indicates the end of the input pattern
So the regex matches an optional - (for the case of negative numbers), followed by one or more decimal digits.
References:
http://www.tldp.org/L...
Aren't promises just callbacks?
...ite asynchronous code in a way that resembles synchronous code and is much more easy to follow:
api().then(function(result){
return api2();
}).then(function(result2){
return api3();
}).then(function(result3){
// do work
});
Certainly, not much less code, but much more readable.
But...
What does 'synchronized' mean?
...interference and memory consistency
errors: if an object is visible to
more than one thread, all reads or
writes to that object's variables are
done through synchronized methods.
In a very, very small nutshell: When you have two threads that are reading and writing to the same 'resource', ...
What is the difference between String.Empty and “” (empty string)?
...n object while string.Empty creates no objectref, which makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, b...
Is there a way to get version from package.json in nodejs code?
...eans that all your dependency version numbers, build and test commands and more are sent to the client.
If you're building server and client in the same project, you expose your server-side version numbers too.
Such specific data can be used by an attacker to better fit the attack on your server...
How does a Breadth-First Search work when looking for Shortest Path?
...ining distance then how would we know the shortest distance,please explain more.
– Gaurav Sehgal
Apr 12 '15 at 19:17
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