If you ever want to join Strings into a String, where each element is separated by some 'separator', I have just recently discovered that there are methods for that (embarrassing).
java.lang.String offers the static method
String.join, which you just give a separator and the set of elements. See the java-doc.
The google guava library provides a
Joiner class. There you just have to call
Joiner.on(", ").join(elems);. Read the explanations on the guava page.
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