title: Creating configurations interface for Model Project (JAVA)
body: <p>Currently I am creating a java Project that will be used by many people to (in theory) create a product, each with their own set of configurations, in a straightforward, fast and with standardized mechanisms.</p>
  
  <p>If I were using a GUI, it would be easier to handle the configurations in different files, however, because I am making it just an editable project, I see myself in the need of putting all the constants in a single class/file so as to centralize the area where the respective engineer configures the product he is creating. Thus I have the following Constants interface:</p>
  
  <pre><code>public interface Constants {
  
      //ROUTE OF FOLDERS
      String PATH_ACTUALIZ = "..\\actualiz\\";
      String PATH_ENTRADAS = "..\\entries\\";
      String PATH_SALIDAS = "..\\outputs\\";
      String PATH_ENTRADAS_CARTAS = PATH_ENTRADAS + "CARTAS\\";
      String PATH_ENTRADAS_ANEXOS = PATH_ENTRADAS + "ANEXOS\\";
      String PATH_SALIDAS_PDF = PATH_SALIDAS + "PDF\\";
  
      //ROUTE OF FILES
      String PATH_FILE_SPOOL_CLIENTE = PATH_ENTRADAS + "spool.txt";
      String PATH_FILE_SPOOL_ERRORES = PATH_SALIDAS + "Reporte_de_Errores.txt";
      String PATH_FILE_BASE_EMAIL = PATH_SALIDAS + "BaseEmail_[OP].txt";
      String PATH_FILE_DATA_VAR = PATH_SALIDAS + "DataVar_[OP].txt";
      String PATH_FILE_BASE = PATH_SALIDAS + "Base.obj";
      String NAME_FILE_LOG = "Log.txt";
  
      //DESIGNER
      String DESIGNER_DELIMITER = "\t"; //Other options "»", "|"
      String DESIGNER_CANAL = "AA01";
  
      //GUI INFORMATION
      String NAME_RESPONSABLE = "JOHN DOE";
      String TITULO_MENSAJE_ERROR = "Error when processing the data.";
      String TITULO_MENSAJE_INFORMACION = "Processing data";
  
      //HTML
      String HTML = "123";
  
      //SEGMENTS
      HashMap&lt;String, String&gt; HMSEGMENTO = new HashMap&lt;String, String&gt;(); //Initialization missing.
  
  }
  </code></pre>
  
  <p>The last line of which is a <code>HashMap</code> because the data involves several pairs of String to String, including one that is returned by default if the key provided isn't found, however I find myself at a standstill because there is no elegant/simple way add data to a Hashmap inside an Interface.</p>
  
  <p>Other solutions I've looked into include the use of Java <code>Properties</code>, but I also wouldn't be able to add data to it in this interface.</p>
  
  <p>So my larger question becomes if I'm even doing this right at all. Any sources or ideas on software development that would direct to the right path would be greatly appreciated.</p>
  
  <p>Finally I understand my question is slightly broad. If there is a way to make it more specific, I would appreciate the help too.</p>