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Type safety: Unchecked cast
...ext().getBean("someMap");
Secondly, the compiler is complaining that you cast the object to a HashMap without checking if it is a HashMap. But, even if you were to do:
if(getApplicationContext().getBean("someMap") instanceof HashMap) {
private Map<String, String> someMap = (HashMap<S...
Assign null to a SqlParameter
...value or a DBNull type value, which are not compatible.
You can of course cast the instance of AgeIndex to be type object which would satisfy the ?: requirement.
You can use the ?? null-coalescing operator as follows
SqlParameter[] parameters = new SqlParameter[1];
SqlParameter planIndexPara...
What happens if you static_cast invalid value to enum class?
...
Answering with a quote from the C++11 and C++14 Standards:
[expr.static.cast]/10
A value of integral or enumeration type can be explicitly converted to an enumeration type. The value is unchanged if the original value is within the range of the enumeration values (7.2). Otherwise, the resulti...
iOS: How to store username/password within an app?
... 3 right-click on frameworks folder and add existing framework. In Xcode 4 select your project, then select target, go to Build Phases tab and click + under Link Binary With Files) and KeychainItemWrapper .h & .m files into your project, #import the .h file wherever you need to use keychain and ...
Store select query's output in one array in postgres
...
There are two ways. One is to aggregate:
SELECT array_agg(column_name::TEXT)
FROM information.schema.columns
WHERE table_name = 'aean'
The other is to use an array constructor:
SELECT ARRAY(
SELECT column_name
FROM information.schema.columns
WHERE table_name = ...
Generating random strings with T-SQL
...st varchar(8000)
declare @step bigint = rand(@seed) * 2147483647;
select @alpha = 'qwertyuiopasdfghjklzxcvbnm'
, @digit = '1234567890'
, @specials = '_@# '
select @first = @alpha + '_@';
set @seed = (rand((@seed+@step)%2147483647)*2147483647);
select @length =...
What is the difference between == and Equals() for primitives in C#?
... accepts the same type.
If you write age.Equals(newAge), the compiler will select int.Equals(int) as the best overload and implicitly convert short to int. It will then return true, since this method simply compares the ints directly.
short also has a short.Equals(short) method, but int cannot be im...
How to parse a string to an int in C++?
...ng.
This leads me to my second piece of advice: do no use Boost's lexical_cast for this. Consider what the lexical_cast documentation has to say:
Where a higher degree of control is
required over conversions,
std::stringstream and
std::wstringstream offer a more
appropriate path. Where
...
Java Class.cast() vs. cast operator
Having being taught during my C++ days about evils of the C-style cast operator I was pleased at first to find that in Java 5 java.lang.Class had acquired a cast method.
...
What are the main purposes of using std::forward and which problems it solves?
... modify these
The third attempt accepts const-references, but then const_cast's the const away:
template <typename A, typename B, typename C>
void f(const A& a, const B& b, const C& c)
{
E(const_cast<A&>(a), const_cast<B&>(b), const_cast<C&>(c))...