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Questions - method-reference

Does Java Method Reference has special treatment to a method whose first argument is the same type of the class being referenced?

I have come across a use of Java Method Reference which I don't know how it can be compiled and executed successfully. I have the following @FunctionalInterface: @FunctionalInterface public interface ...
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Genzer

java

method-reference

Votes: 0

Answers: 1

Latest Answer

According to the JLS A functional interface is an interface that has just one abstract method (aside from the methods of Object), and thus represents a single function contract. NotifyFunction defin...
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Alexander Ivanchenko

Why and When should I use Functional Interfaces

Say I am writing a Consumer which prints something on the console. Then why shouldn't I directly use the System.out.println() method instead of creating a Consumer? Similarly, say I want to return a r...
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Ashish Singh

java

lambda

method-reference

functional-interface

Votes: 0

Answers: 2

Latest Answer

Functional interfaces should of course only be used where it is reasonable, and not everywhere. It is closely related to abstraction and generalization. Good examples for this can be seen in the Java ...
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Marcono1234

Compilation error while merging two Maps is being issued for Map.Entry::getKey

Whenever I use Map.Entry::getKey in my streams for my public methods, I get an issue around my method not being static. I even tried making my method static, and it didn't work. Below is the compile e...
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Mabel Oza

java

java-8

hashmap

java-stream

method-reference

Votes: 0

Answers: 2

Latest Answer

You can use Map.Entry::getKey and Map.Entry::getValue but the error is caused by something else. Map.Entry::getValue and Integer::sum return different types. The definition of toMap method explains wh...
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frascu

Using method references as listeners with observer pattern

the usage of method references as listeners in an observer pattern does not work. Example: public class ObserverWithMethodReferenceAsListenerTest { class ListenerCurator { private fi...
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opfau

java

observer-pattern

method-reference

Votes: 0

Answers: 2

Latest Answer

From the Oracle documentation on Method References: Method references enable you to do this; they are compact, easy-to-read lambda expressions for methods that already have a name. A method referenc...
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GhostCat again on strike

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