charAt( ) method: It is used to extract one character from a string.
char charAt(int index)
here, index is used to determine the location of the character in the string.
getChars( ) method: It is used to extract more than one character from a string.
void getChars(int sourceStart, int sourceEnd, char target[ ], int targetStart)
here, sourceStart specifies the beginning of the string which will be extracted.
sourceEnd for the end of the string.
target is the location where the string will be extracted.
getBytes( ) method: It works like getChars() method, only difference is that it stores characters as bytes array.
byte[ ] getBytes( )
toCharArray( ) method: It is used to convert a string in to a character array.
char[ ] toCharArray( )