What "->" means in Java -


this question has answer here:

i'm beginner in java simple things new me. besides level google doesn't want search such keywords "->" :)

i found here. think code correct.

please me understand expression mean?

firstnamecol.setoneditcommit(         (celleditevent<person, string> t) -> {             ((person) t.gettableview().getitems().get(                     t.gettableposition().getrow())                     ).setfirstname(t.getnewvalue());

that lambda expression - https://docs.oracle.com/javase/tutorial/java/javaoo/lambdaexpressions.html.

it new in java 8.

when interface has 1 method , annotated @functionalinterface functional interface. allows use "->" syntax bypass lot of verbose boilerplate code.

you can replace

btn.setonaction(new eventhandler<actionevent>() {      @override     public void handle(actionevent event) {         system.out.println("hello world!");     } });

with 

btn.setonaction(   event -> system.out.println("hello world!") );

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