public String concat(String str)Concatenates the specified string to the end of this string.
If the length of the argument string is 0, then this String object is returned. Otherwise, a new String object is created, representing a character sequence that is the concatenation of the character sequence represented by this String object and the character sequence represented by the argument string.
Examples:
"cares".concat("s") returns "caress"
"to".concat("get").concat("her") returns "together"
Parameters:
str - the String that is concatenated to the end of this String.
Returns:
a string that represents the concatenation of this object's characters followed by the string argument's characters.
Throws:
NullPointerException - if str is null.