Constructor References
Description
We can use constructor to create a lambda expression.
The syntax to use a constructor reference is
ClassName::new
The keyword new refers to the constructor of the class. The compiler chooses a constructor based on the context.
Example
import java.util.function.Function;
import java.util.function.Supplier;
// w ww.j av a2s . c o m
public class Main{
public static void main(String[] argv){
Supplier<String> func1 = () -> new String();
System.out.println("Empty String:"+func1.get());
Function<String,String> func2 = str -> new String(str);
System.out.println(func2.apply("java2s.com"));
Supplier<String> func3 = String::new;
System.out.println("Empty String:"+func3.get());
Function<String,String> func4 = String::new;
System.out.println(func4.apply("java2s.com"));
}
}
The code above generates the following result.
