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java - Search a file for a String and return that String if found

How can you search through a txt file for a String that the user inputs and then return that String to the console. I've written some code that doesn't work below, but I hope it can illustrate my point...

public static void main(String[] args) {
  searchforName();
}

   private static void searchForName() throws FileNotFoundException {
    File file = new File("leaders.txt");
    Scanner kb = new Scanner(System.in);
    Scanner input = new Scanner(file);

    System.out.println("Please enter the name you would like to search for: ");
    String name = kb.nextLine();


    while(input.hasNextLine()) {
        System.out.println(input.next(name));
    }
}

The "leaders.txt" file contains a list of names.

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1 Answer

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by (71.8m points)

You can create a seperate Scanner to read the file line by line and do a match that way...

final Scanner scanner = new Scanner(file);
while (scanner.hasNextLine()) {
   final String lineFromFile = scanner.nextLine();
   if(lineFromFile.contains(name)) { 
       // a match!
       System.out.println("I found " +name+ " in file " +file.getName());
       break;
   }
}

With regards to whether you should use a Scanner or a BufferedReader to read the file, read this answer.


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