String::repeat
". ".repeat( 7 ) // Seven period-with-space pairs: . . . . . . .
Java 11中的新功能是String::repeat完全符合您要求的方法:
String str = "abc";String repeated = str.repeat(3);repeated.equals("abcabcabc");它的Javadoc说:

String::repeat
". ".repeat( 7 ) // Seven period-with-space pairs: . . . . . . .
Java 11中的新功能是String::repeat完全符合您要求的方法:
String str = "abc";String repeated = str.repeat(3);repeated.equals("abcabcabc");它的Javadoc说: