How do I use a delimiter with Scanner useDelimiter in Java

Question

sc   new Scanner new File dataFile    sc useDelimiter     r n      I don t understand how delimiter works  can someone explain this in layman terms

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For example   String myInput   null  Scanner myscan   new Scanner System in  useDelimiter    n    System out println  Enter your input      myInput   myscan next    System out println myInput     This will let you use Enter as a delimiter   Thus  if you input   Hello world  ENTER    it will print  Hello World

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The scanner can also use delimiters other than whitespace   Easy example from Scanner API   String input    quot 1 fish 2 fish red fish blue fish quot          s  means 0 or more repetitions of any whitespace character      fish is the pattern to find  Scanner s   new Scanner input  useDelimiter  quot   s fish  s  quot      System out println s nextInt          prints  1  System out println s nextInt          prints  2  System out println s next             prints  red  System out println s next             prints  blue      don t forget to close the scanner    s close      The point is to understand the regular expressions  regex  inside the Scanner  useDelimiter  Find an useDelimiter tutorial here   To start with regular expressions here you can find a nice tutorial  Notes abc       Letters 123       Digits  d      Any Digit  D      Any Non-digit character         Any Character         Period  abc    Only a  b  or c   abc   Not a  b  nor c  a-z    Characters a to z  0-9    Numbers 0 to 9  w      Any Alphanumeric character  W      Any Non-alphanumeric character  m      m Repetitions  m n    m to n Repetitions         Zero or more repetitions         One or more repetitions         Optional character  s      Any Whitespace  S      Any Non-whitespace character           Starts and ends           Capture Group  a bc   Capture Sub-group         Capture all  ab cd  Matches ab or cd

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With Scanner the default delimiters are the whitespace characters   But Scanner can define where a token starts and ends based on a set of delimiter  wich could be specified in two ways    Using the Scanner method  useDelimiter String pattern  Using the Scanner method   useDelimiter Pattern pattern  where Pattern is a regular expression that specifies the delimiter set    So useDelimiter   methods are used to tokenize the Scanner input  and behave like StringTokenizer class  take a look at these tutorials for further information    Setting Delimiters for Scanner Java util Scanner useDelimiter   Method   And here is an Example   public static void main String   args            Initialize Scanner object     Scanner scan   new Scanner  Anna Mills Female 18           initialize the string delimiter     scan useDelimiter              Printing the tokenized Strings     while scan hasNext             System out println scan next                  closing the scanner stream     scan close        Prints this output   Anna Mills Female 18

[java] How do I use a delimiter with Scanner.useDelimiter in Java?

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