@Override
  public boolean canHaveCaret(CodeDisplayCoordinate coordinate) {
    return coordinate.getColumn() == 0 ? false : true;
  }
The code display is a large array of rows to be displayed. Each row is an array of fields of
length "Columns". Each field is an array of lines.
java/zylib/src/main/java/com/google/security/zynamics/zylib/gui/CodeDisplay/CodeDisplayModelExample.java