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Java Enum definition
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Your solution has an unchecked cast: return (CHILD) this; Consider adding a getThis() method: protected CHILD getThis() { return this; } See: angelikalanger.com/GenericsFAQ/FAQSections/…
– Roland
Nov 28 '1...
How can I convert NSDictionary to NSData and vice versa?
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For NSData -> NSDictionary, the cast to NSDictionary seems unnecessary.
– Pang
Dec 30 '15 at 8:11
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Test if a property is available on a dynamic variable
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@ministrymason If you mean casting to IDictionary and work with that, that works only on ExpandoObject, it won't work on any other dynamic object.
– svick
Jul 12 '12 at 16:58
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C# - Keyword usage virtual+override vs. new
...a Bar, but we are storing it in a variable of type Foo (this is similar to casting it)
Then the result will be as follows, depending on whether you used virtual/override or new when declaring your classes.
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How do I get a class instance of generic type T?
...(getClass(), AbstractHibernateDao.class);
this.RECORD_COUNT_HQL = "select count(*) from " + this.genericType.getName();
this.FIND_ALL_HQL = "from " + this.genericType.getName() + " t ";
}
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jQuery hasAttr checking to see if there is an attribute on an element [duplicate]
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What about api.jquery.com/has-attribute-selector
– Aamir Afridi
Jan 30 '13 at 14:19
3
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How do I force Postgres to use a particular index?
...d, client_id, date, and description. You want to run the following query:
SELECT client_id, SUM(amount)
FROM transactions
WHERE date >= 'yesterday'::timestamp AND date < 'today'::timestamp AND
description = 'Refund'
GROUP BY client_id
PostgreSQL may choose to use the index transaction...
How to import load a .sql or .csv file into SQLite?
...Hey!');
Insert into T values (2, 'Hey, You!');
.mode csv
.output test.csv
select * from T;
Contents of test.csv:
1,Hey!
2,"Hey, You!"
delete from T;
.import test.csv T
Error: test.csv line 2: expected 2 columns of data but found 3
It seems we must transform the csv into a list of Insert statem...
Best way to store time (hh:mm) in a database
...t a glance and performing calculations on them are straightforward.
E.g.
SELECT DATEDIFF(MINUTE, event_start, event_end)
ISO8601 date standard
If using SQLite then you don't have this, so instead use a Text field and store it in ISO8601 format eg.
"2013-01-27T12:30:00+0000"
Notes:
This use...
Covariance, Invariance and Contravariance explained in plain English?
...fferent generics parameters. Their relationships are the reason why we can cast them.
Co and Contra variance are pretty logical things. Language type system forces us to support real life logic. It's easy to understand by example.
Covariance
For instance you want to buy a flower and you have two ...