Question

Actually i’m comparing two string which returns true when i use equals method. Whereas when i use compareTo method it returns 22.

Also i want to know at what place those two Strings differ. Using java how do i find this?

Thanks in advance.

Answer 1

According to the documentation of compareTo()

[…] If two strings are different, then
either they have different characters
at some index that is a valid index
for both strings, or their lengths are
different, or both. If they have
different characters at one or more
index positions, let k be the smallest
such index; then the string whose
character at position k has the
smaller value, as determined by using
the < operator, lexicographically
precedes the other string. In this
case, compareTo returns the difference
of the two character values at
position k in the two string — that
is, the value:

 this.charAt(k)-anotherString.charAt(k)

If there is no index position at which
they differ, then the shorter string
lexicographically precedes the longer
string. In this case, compareTo
returns the difference of the lengths
of the strings — that is, the value:

 this.length()-anotherString.length()

Hence, 22 is not the position of the differing character in the two strings, but the distance between the first dissimilar characters.

As for your second question, I believe a simple iteration through the characters in both strings will allow you to pinpoint easily the first character position where they differ