When I run the code below the compareTo returns a value less than zero.
public class compare
{
public static void main ( String [] args )
{
String str1 = "araraaaaaa";
String str2 = "asa";
int comp = str1.compareTo(str2);
System.out.println(""+comp) // printa -1 na tela
}
}
Theoretically, str1 is not greater than str2 ?
Why does it return negative?
The compareTo method of the String class is used to sort the String s alphabetically *, not by size. In this way we have "araraaaaaa" comes before "asa" , and therefore compareTo gives -1, because when comparing the first letter the two String s are equal ( a ) and when comparing the second, r comes before s .
To compare the% s of% s by size, you should invoke the String method of length s and then compare the sizes directly. (Suggested Marcelo Bonifazio )
It is also worth remembering that whenever we have String returning -1 (or some other negative number) it means that a.compareTo(b) precedes a , if it returns +1 (or some other positive number) then b happens a and if it returns 0 then b and a are similar. However, the exact definition of "precede", "succeed" and "similar" is at the discretion of each class that implements b . In the case of class compareTo the definition is given by the alphabetical order *.
(*) - Actually the comparison is not exactly alphabetic, but is based on the comparison of sequences of numeric values of unicode codepoints.