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+public class HelloStringChangeCase %7B%0A%0A    public static void main(String... args) %7B%0A        System.out.println(%22Hello String Change Case!%22);%0A%0A        String str60 = %22Hello World!%22.toLowerCase();%0A        String str61 = %22Hello World!%22.toUpperCase();%0A%0A        System.out.println(%22---%22);%0A        System.out.printf(%22%5C%22Hello World!%5C%22.toLowerCase(); = %3C%25s%3E%5Cn%22, str60);%0A        System.out.printf(%22%5C%22Hello World!%5C%22.toUpperCase(); = %3C%25s%3E%5Cn%22, str61);%0A    %7D%0A%7D%0A

Create HelloStringChangeCase.java