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/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.stream.Collectors;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		getList().forEach(System.out::println);
	}
 
	 static List<String[]> getList() {
        return Optional.ofNullable(getListAsObjectFromSomewhere())
            .map(listObject -> (List<String[]>)listObject)
            // return in reversed order
            .map(list -> list.stream().sorted(Comparator.reverseOrder()).collect(Collectors.toList()))
            .orElse(Collections.<String[]>emptyList());
    }
 
	static Object getListAsObjectFromSomewhere() {
		return List.of(new String[]{"1", "hi"}, new String[]{"2", "hello"});
	}
}

Main.java:20: error: incompatible types: inference variable T has incompatible bounds
            .map(list -> list.stream().sorted(Comparator.reverseOrder()).collect(Collectors.toList()))
                                      ^
    lower bounds: Comparable<? super T>
    lower bounds: String[]
  where T is a type-variable:
    T extends Comparable<? super T> declared in method <T>reverseOrder()
Main.java:21: error: incompatible types: Object cannot be converted to List<String[]>
            .orElse(Collections.<String[]>emptyList());
                   ^
Note: Main.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output
2 errors

Standard output is empty