Insert multiple words to a String issue

Question

I want insert multiple words in a String, But offset is relative to the original String:

StringBuffer sb = new StringBuffer("abcdefghijk");
sb.insert(3,"123");
sb.insert(5,"456");
System.out.println(sb); 

Result:

abc124563defghijk

I'd like the Result is:

abc123de456fghijk

How can I do? Thanks for any suggestion.

Answer 1

Reverse the order of the two inserts, and you'll get the expected result. More generally, start with the larger insertion indices and proceed to the smaller.

It is also worth noting that StringBuilder should be preferred to StringBuffer.