[java] Tokenizing Error: java.util.regex.PatternSyntaxException, dangling metacharacter '*'

The first answer covers it.

Im guessing that somewhere down the line you may decide to store your info in a different class/structure. In that case you probably wouldn't want the results going in to an array from the split() method.

You didn't ask for it, but I'm bored, so here is an example, hope it's helpful.

This might be the class you write to represent a single person:


class Person {
            public String firstName;
            public String lastName;
            public int id;
            public int age;

      public Person(String firstName, String lastName, int id, int age) {
         this.firstName = firstName;
         this.lastName = lastName;
         this.id = id;
         this.age = age;
      }  
      // Add 'get' and 'set' method if you want to make the attributes private rather than public.
} 

Then, the version of the parsing code you originally posted would look something like this: (This stores them in a LinkedList, you could use something else like a Hashtable, etc..)


try 
{
    String ruta="entrada.al";
    BufferedReader reader = new BufferedReader(new FileReader(ruta));

    LinkedList<Person> list = new LinkedList<Person>();

    String line = null;         
    while ((line=reader.readLine())!=null)
    {
        if (!(line.equals("%")))
        {
            StringTokenizer st = new StringTokenizer(line, "*");
            if (st.countTokens() == 4)          
                list.add(new Person(st.nextToken(), st.nextToken(), Integer.parseInt(st.nextToken()), Integer.parseInt(st.nextToken)));         
            else            
                // whatever you want to do to account for an invalid entry
                  // in your file. (not 4 '*' delimiters on a line). Or you
                  // could write the 'if' clause differently to account for it          
        }
    }
    reader.close();
}

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