How to log JAVA Webservice to a file

Question

I build a Service with JAX-RS (Jersey 2.0) and tried to implement a logger who writes down events like errors or results from the requests. Works fine! :) Unfortunately it creates a File every time the service is called but it would be nice that he writes it in one file.

Have a look at my code (it's just the relevant part):

package webservice.feedbacks;

import java.io.IOException;
// imports

@Path("webservice")
public class DeleteFeedback {

Logger logger = Logger.getLogger("Feedbacklogger");
@POST
@Path("/deleteFeedback")
@Consumes(MediaType.APPLICATION_JSON + ";charset=UTF-8")
@Produces("text/plain")
public String setFeedbacks(String incoming){

    FileHandler fh;
    JSONObject jsonObj = new JSONObject(incoming);

    try {
        fh = new FileHandler("D:/Eclipse-Projekte/SmartliveService/logs/DeleteFeedback_log.log");
        logger.addHandler(fh);
        SimpleFormatter formatter = new SimpleFormatter();
        fh.setFormatter(formatter);
        logger.info("----- BEGINN DES PROTOKOLLS -----");
    } catch (SecurityException | IOException e) {e.getMessage();}

    int id = jsonObj.getInt("id");

    String result = executeQuery(id);

    logger.info("----- ENDE DES PROTOKOLLS -----");

    return result;
}

private String executeQuery(int id) {

    try {
        Class.forName("com.mysql.jdbc.Driver");
    } catch (ClassNotFoundException e) {logger.info("Treiberfehler: " + e.getMessage());}

    Connection con = null;
    Statement stmt = null;

    try{...} catch(SQLException e){
        logger.info("SQL-Fehler: " + e.getMessage());
        return "error";
    } finally {     
        try { if (stmt != null) stmt.close();} catch (Exception e) {logger.info("Das Statement konnte nicht geschlossen werden: " + e.getMessage());};
        try { if (con != null) con.close();} catch (Exception e) {logger.info("Die Verbindung konnte nicht geschlossen werden: " + e.getMessage());};
    }
    return "success";
}
}}

As you can see I created a FileHandler . I got this from a tutorial because I'm not that familiar with JAVA as I had been a few years ago. The code just made a Database-query and sends the results.

So, how do I have to write my code that it logs to one file instead of creating a new one every time the interface is called?

Hope someone can help me.

Answer 1

You should not initialize the filehandler everytime method is called. Maybe you should make it static or initialize it in the constructor. See append also.