print TreeMap<String, TreeSet<String>> in Java 8

Question

I am trying to print the

TreeMap<String, TreeSet<String>> abbreviations in Java

I tried:

if (abbreviations.size() > 0)
        abbreviations.forEach((x, y) -> {                     
            System.out.println(String.format("%-7s   : %-100s ", x, y)); 
        });

It printing like this:

US        : [ Unity Status,  Unresolved Sample]                                                                  
VC        : [ Value Color,  Value Contex,  Value Context,  Video Conference,  Visibility Created,  Visit Created,  Visits Completed] 

But I like to print without square brackets.

US        : Unity Status,  Unresolved Sample                                                                  
VC        : Value Color,  Value Contex,  Value Context,  Video Conference,  Visibility Created,  Visit Created,  Visits Completed

What can I try next?

Answer 1

有很多方法可以做到这一点，其中之一是像这样使用String.join ：

String.format("%-7s   : %-100s ", x, String.join(", ", y))