使用Hashmaps了解两个或更多键

Question

I am having an issue with a hashmap. In my hashmap method i want to have two or more keywords as a key, oppose to having one. For example I want the user to input some sentence containing two or more keywords assuming "professor name" is a keyword. For example

    String[] temp3 = { "instructor","teacher","mentor" };
    responses.put("professor name", temp3);

And the user enters "what is the professor name" the code just hangs. But on the other hand, if

  String[] temp3 = { "instructor","teacher","mentor" };
    responses.put("professor", temp3);

the code works. So I want to be able to enter some sentence containing two or more keywords oppose to one. I will appreciate any sort of assistance.

Here is my hashmap method

  private static HashMap<String, String[]> populateSynonymMap() {

    String[] temp1 = { "instructor","teacher","mentor" };
    responses.put("professor name", temp1);
    String[] temp2 = { "amount of test","test load","quantity of test" };

    return responses;
}

and here is my main method

    public static void main(String args[]) throws ParseException, IOException {
    /* Initialization */
    HashMap<String, String[]> synonymMap = new HashMap<String, String[]>();
    synonymMap = populateSynonymMap(); // populate the map


    Scanner scanner = new Scanner(System.in);
    String input = null;
   /*End Initialization*/
    System.out.println("Welcome To DataBase ");
    System.out.println("What would you like to know?");

    System.out.print("> ");
    input = scanner.nextLine().toLowerCase();
    String[] inputs = input.split(" ");
      for (String ing : inputs) { // iterate over each word of the sentence.
        boolean found = false;
        for (Map.Entry<String, String[]> entry : synonymMap.entrySet()) {
            String key = entry.getKey();
            String[] value = entry.getValue();
            if (key.equals(ing) || Arrays.asList(value).contains(ing)) {

                found = true;
                parseFile(entry.getKey());``
            }
          break;
     }
                if (found) {
            break;
        }


    }
}

Assuming that the ParseFile method works

Answer 1

Use the type HashMap<List<String>,String[]> or HashMap<Set<String>,String[]> for the cases where the order does and does not matter respectively, in place of HashMap<String,String[]> .

In the first case, your keys are of type List<String> , and in the second case they are of type Set<String> .

Best practice would be to wrap all keys with Collections.unmodifiable* methods before using them as keys - if they are modified while in HashMap entires, the behavior of your program will be undefined.

Answer 2

I would use String contains method to check multiple words. This will solve your problem of checking single word like 'professor' or multiple words like 'What is your professor name' problem.

    System.out.print("> ");
    input = scanner.nextLine().toLowerCase();

    for (Map.Entry<String, String[]> entry : synonymMap.entrySet()) {
        String key = entry.getKey();
        String[] value = entry.getValue();
        if (input.contains(key) || key.contains(input)) {
            System.out.println("Input found in database -> " +Arrays.asList(value));
            break;
        }
    }

Now this will make it work with single word or multiple word. But this works when words are entered in same order. You can make it as elaborate as you like.

For example you may extend this to separate words of input and output from sentence from the sets and then find how many words matches etc.And I recommend that you use some different data structure which makes this task natural looking. You may think about having your database organized by words and synonyms relation so then you don't have to worry about cases where value from one synonym list has other synonym etc. And lookup can be just based on words.