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Siu KWAN Yuen
Courses Plus Student 2,898 PointsHelp!! Stream and Data Structure
Will operation of a stream change its original object's data structures?
What is the data structure when
List <String> m. stream(). filter( m-> isMPass(m)) <- what is the data structure of this output?
2 Answers
Lucas Felix Sampaio
802 PointsHi Siu.
Stream doesn't modify the original data structure.
The output of this:
List <String> m. stream(). filter( m-> isMPass(m))
is a Stream. The filter method returns a Stream.
You can collect the output in a new List, using collect() method and the Collectors class:
List<String> newList = m. stream(). filter( m-> isMPass(m)).collect(Collectors.toList())
Siu KWAN Yuen
Courses Plus Student 2,898 PointsOh, Thanks!!! Is this stream the same as the I/O stream? So the output is not a way to store data or not a data structure and that's why it needs a terminal operation.
Lucas Felix Sampaio
802 PointsHi! I believe that are not the same thing, but the idea should be. :) Yes, you need a terminal operation that will return a result or a new data structure with the modifications! excuse my english