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Java Java Data Structures - Retired Exploring the Java Collection Framework Maps

Rashadat Mirzayev
Rashadat Mirzayev
14,601 Points
Posted by Rashadat Mirzayev
Rashadat Mirzayev
14,601 Points

I do not get the method

in this line: List<Treet> authoredTreets = treetsByAuthor.get(treet.getAuthor());

getAuthor() only get the author not the treet, wright? it suppose to put author of the treet to authoredTreets?

2 Answers

Omar Amin
PLUS
Omar Amin
Courses Plus Student 1,194 Points
Omar Amin
Omar Amin
Courses Plus Student 1,194 Points

The first getAuthor() method returns the author of the treet. The second get method which is invoked by the treetsByAuthor map returns the value associated with the key (in this case the returned author). This returned value (which is the treet) will be put in the authoredTreets list. It might be null if the author is not in the treetsByAuthor map. I hope you got it.