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java - List of String Arrays overwriting itself

First ever question here, complete newbie so try to take it easy on me. I'm trying to figure out what's wrong here:

public List<String[]> idOnlyQuery(String searchTerm, Connection conn){

    List<String[]> result = new ArrayList<String[]>();
    String[] rowResult = new String[7];

    Statement stmt = null;      
    try {
      stmt = conn.createStatement();
      ResultSet rs = stmt.executeQuery( "SELECT * FROM Jets WHERE CurrentID LIKE '" + searchTerm + "%'");
      while(rs.next()){

          String currentId= rs.getString("CurrentId");
          String manufacturer = rs.getString("Constructor");
          String type = rs.getString("ACType");
          String series = rs.getString("Series");
          String index = rs.getString("KeyNo");
          String operator = rs.getString("Operator");
          String baseAirport = rs.getString("Home_Airfield");
          rowResult[0] = (currentId);
          rowResult[1] = (manufacturer);
          rowResult[2] = (type);
          rowResult[3] = (series);
          rowResult[4] = (operator);
          rowResult[5] = (baseAirport);
          rowResult[6]= (index);
          result.add(rowResult);
      }
    System.out.println(result.get(0)[0]);

This method returns a list of string arrays, these arrays are retrieved from an SQLite database. Everything works apart from the fact that the string arrays in my result List seem to be getting overwritten every time the while loop repeats itself. The last println always gives me the currentId of the last row retrieved from the database, but if I put a println inside the while loop it returns the appropriate data on each while cycle. I really can't figure out where my String[] elements are getting overwritten. It's probably really obvious but I've spent hours looking online to check if I'm doing the add procedure correctly and still no joy. HELP!

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1 Answer

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You need to create the rowResult array in the loop. Your list just holds a pointer to the array and you are basically only working with one instance all the time.


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