How do I write an equivalent of this in Java?
// C++ Code
template< class T >
class SomeClass
{
private:
T data;
public:
SomeClass()
{
}
void set(T data_)
{
data = data_;
}
};
views:
2091answers:
3
+5
A:
class SomeClass<T> {
private T data;
public SomeClass() {
}
public void set(T data_) {
data = data_;
}
}
You probably also want to make the class itself public, but that's pretty much the literal translation into Java.
There are other differences between C++ templates and Java generics, but none of those are issues for your example.
Laurence Gonsalves
2009-12-06 04:20:21
Actually, one difference, which isn't a generic/template thing but a more fundamental difference between C++ and Java, is that the set method in C++ copies the supplied object, while the Java version just copies the reference.
Laurence Gonsalves
2009-12-06 04:25:28
Wow, and the cool thing about "generics" is that I can even express something like public class SomeClass<T extends OtherClass>! I dont think that ability is present in C++. So cool!
ShaChris23
2009-12-06 04:33:54
ShaChris23: the prevalent idiom in the C++ stdlib is to use duck typing: "if all the attempted uses work with the object, it has the interface expected" (std::reverse_iterator being a good, clear example), and this is similar to Python and [my understanding of] Go. It is still sometimes useful to make those restrictions yourself (or at least people ask for it :P), and you can use boost::enable_if, static asserts (with type traits to detect inheritance in this case), and similar for that. Concepts were supposed to help address this, but that's another story.
Roger Pate
2009-12-06 06:39:45
+1
A:
You use "generics" to do this in Java:
public class SomeClass<T> {
private T data;
public SomeClass() {
}
public void set(T data) {
this.data = data;
}
};
Wikipedia has a good description of generics in Java.
Moishe
2009-12-06 04:21:58
A:
/**
* This class is designed to act like C#'s properties.
*/
public class Property<T>
{
private T value;
/**
* By default, stores the value passed in.
* This action can be overridden.
* @param _value
*/
public void set (T _value)
{
value = _value;
}
/**
* By default, returns the stored value.
* This action can be overridden.
* @return
*/
public T get()
{
return value;
}
}
Bill
2010-06-16 14:14:59