public boolean startsWith (String prefix, int toffset)

Tests if the substring of this string beginning at the specified index starts with the specified prefix.

prefix    the prefix.
toffset    where to begin looking in this string.

Returns:  true if the character sequence represented by the argument is a prefix of the substring of this object starting at index toffset; false otherwise. The result is false if toffset is negative or greater than the length of this String object; otherwise the result is the same as the result of the expression