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class ShowHeapError {
  private Vector<String> names = new Vector<String>();
  private final InputStreamReader input;
  private final BufferedReader reader;

  public ShowHeapError(String filename) throws IOException {
    this.input = new FileReader(filename);
    this.reader = new BufferedReader(input);
  }

  public void addNames() throws IOException {
    try {
      String newName;
      while (((newName = reader.readLine()) != null) &&
             (newName.equalsIgnoreCase("quit") == false)) {
        names.addElement(newName);
        System.out.println("adding " + newName);
      }
    } finally {
      input.close();
    }
  }

  public static void main(String[] args) throws IOException {
    if (args.length != 1) {
      System.out.println("Arguments: [filename]");
      return;
    }
    ShowHeapError demo = new ShowHeapError(args[0]);
    demo.addNames();
  }
}

class ShowHeapError {
  // ... other methods

  static public String readLimitedLine(Reader reader, int limit) throws IOException {
    StringBuilder sb = new StringBuilder();
    for (int i = 0; i < limit; i++) {
      int c = reader.read();
      if (c == -1) {
        return null;
      }
      if (((char) c == '\n') || ((char) c == '\r')) {
        break;
      }
      sb.append((char) c);
    }
    return sb.toString();
  }

  static public final int lineLengthLimit = 1024;
  static public final int lineCountLimit = 1000000;

  public void addNames() throws IOException {
    try {
      String newName;
      for (int i = 0; i < lineCountLimit; i++) {
        newName = readLimitedLine( reader, lineLengthLimit);
        if (newName == null) {
          break;
        }
        if (newName.equalsIgnoreCase("quit")) {
          break;
        }

        names.addElement(newName);
        System.out.println("adding " + newName);
      }
    } finally {
      input.close();
    }
  }

}

class ShowHeapError {
  // ...other methods
  static public final int fileSizeLimit = 1000000;

  public ShowHeapError(String filename) throws IOException {
    if (Files.size( Paths.get( filename)) > fileSizeLimit) {
      throw new IOException("File too large");
    }
    this.input = new FileReader(filename);
    this.reader = new BufferedReader(input);
  }

  // ...other methods
}

/** Assuming the heap size as 512 MB (calculated as 1/4th of 2 GB RAM = 512 MB)
 *  Considering long values being entered (64 bits each, the max number of elements
 *  would be 512 MB/64bits = 67108864)
 */
public class ShowHeapError {
  Vector<Long> names = new Vector<Long>(); // Accepts unknown number of records
  long newID = 0L;
  int count = 67108865;
  int i = 0;
  InputStreamReader input = new InputStreamReader(System.in);
  Scanner reader = new Scanner(input);

  public void addNames() {
    try {
      do {
        // Adding unknown number of records to a list
        // The user can enter more IDs than the heap can support and thus 
        // exhaust the heap. Assume that the record ID is a 64 bit long value

    
      System.out.print("Enter recordID (To quit, enter -1): ");
        newID = reader.nextLong();
   
  
      names.addElement(newID);
        i++;
      } while (i < count || newID != -1);
    } finally {
  // Close "reader" and "input"input.close();
    }
  }

  public static void main(String[] args) {
    ShowHeapError demo = new ShowHeapError();
    demo.addNames();
  }
}