涉及字符串的Java程序输出的问题

Question

class Blue_ManTest{

    public static void main(String[] args){
        String name = "I LOVE JAVAWORLD";
        int index1 = name.indexOf(" ");
        int index2 = name.lastIndexOf(" ");
        String str1 = name.substring(0, index1);
        String str2 = name.substring(index1 + 1, index1+ 5);
        String str3 = name.substring(index2 + 5);
        System.out.println(str3 + ", " + str1 + " " + str2 + ".");
    }
}   

I am having trouble figuring out what would be the output of this program I think I know it but I am not sure.

I did this I Love JavaWorld with 0 corresponding to j and 15 to D with 1 being the space between.

for str1 I get I

for str2 I get Love

but for str3 I get avaWorld

But str3 seems wrong to me as it would print out.

avaWorld, I  Love.    

Answer 1

Your str3 variable is taking a substring that starts at index2 + 5 where index2 is the index of the last space in your input string:

int index2 = name.lastIndexOf(" ");

That is, index2 is 6. And of course 6 + 5 is 11.