- added explicit help screen option

Author: keinproblem

sampling-message-client/src/main/java/de/dhbw/ravensburg/verteiltesysteme/client/CommandLineClient.java

@@ -22,6 +22,13 @@ public class CommandLineClient extends Client {
     CommandLineClient() {
         options = new Options();
 
+        options.addOption(Option.builder("h")
+                .longOpt("help")
+                .hasArg(false)
+                .required(false)
+                .desc("print help")
+                .build());
+
         options.addOption(Option.builder("n")
                 .longOpt("name")
                 .hasArg(true)
@@ -81,6 +88,10 @@ public void run(String[] args) {
             return;
         }
 
+        if (commandLine.hasOption("help")) {
+            exitWithHelpScreen();
+        }
+
         final String address = commandLine.getOptionValue("address");
         final int port = Integer.parseInt(commandLine.getOptionValue("port"));
 
@@ -277,6 +288,10 @@ private void deleteSamplingMessage(CommandLine commandLine, SamplingMessageGrpc.
      */
     private void exitWithError(String errorMessage) {
         log.error(errorMessage);
+        this.exitWithHelpScreen();
+    }
+
+    private void exitWithHelpScreen() {
         helpFormatter.printHelp("sampling-message-client", options);
         System.exit(1);
     }

sampling-message-server/src/main/java/de/dhbw/ravensburg/verteiltesysteme/server/Main.java

@@ -3,8 +3,9 @@
 import de.dhbw.ravensburg.verteiltesysteme.server.service.ServiceConfig;
 import de.dhbw.ravensburg.verteiltesysteme.server.util.ServerCommandLineParser;
 import lombok.extern.slf4j.Slf4j;
-import org.apache.commons.cli.HelpFormatter;
-import org.apache.commons.cli.ParseException;
+import org.apache.commons.cli.*;
+
+import static de.dhbw.ravensburg.verteiltesysteme.server.util.ServerCommandLineParser.defaultOptions;
 
 /**
  * Class providing the application entry point.
@@ -21,17 +22,19 @@ public class Main {
     public static void main(String[] args) {
         final ServiceConfig serviceConfig;
         try {
-            serviceConfig = ServerCommandLineParser.fromCliArgs(args);
+            final CommandLineParser serverCommandLineParser = new DefaultParser();
+            final CommandLine commandLine = serverCommandLineParser.parse(defaultOptions(), args);
+            if (commandLine.hasOption("help")) {
+                exitWithHelpScreen();
+            }
+            serviceConfig = ServerCommandLineParser.fromCliArgs(commandLine);
         } catch (ParseException e) {
             e.printStackTrace();
             log.debug("ParsingError: ", e.getMessage());
-            log.error(e.getMessage());
-            new HelpFormatter().printHelp("sampling-message-client", ServerCommandLineParser.defaultOptions());
-            System.exit(1);
+            exitWithError(e.getMessage());
             //dead code to satisfy for debugger
             return;
         }
-        //final ServiceConfig serviceConfig = new ServiceConfig(255, 32, 32, 8080);
 
         final ServiceEndpoint serviceEndpoint = new ServiceEndpoint(serviceConfig);
 
@@ -51,4 +54,19 @@ public static void main(String[] args) {
             log.error("Interrupted while running: ", e);
         }
     }
+
+    /**
+     * Prints an error message before exiting the program with an error exit code of 1.
+     *
+     * @param errorMessage Message to be displayed on the console during the program shutdown
+     */
+    private static void exitWithError(String errorMessage) {
+        log.error(errorMessage);
+        exitWithHelpScreen();
+    }
+
+    private static void exitWithHelpScreen() {
+        new HelpFormatter().printHelp("sampling-message-server", defaultOptions());
+        System.exit(1);
+    }
 }

sampling-message-server/src/main/java/de/dhbw/ravensburg/verteiltesysteme/server/util/ServerCommandLineParser.java

@@ -1,7 +1,9 @@
 package de.dhbw.ravensburg.verteiltesysteme.server.util;
 
 import de.dhbw.ravensburg.verteiltesysteme.server.service.ServiceConfig;
-import org.apache.commons.cli.*;
+import org.apache.commons.cli.CommandLine;
+import org.apache.commons.cli.Option;
+import org.apache.commons.cli.Options;
 
 /**
  * Utility class for CLI related stuff
@@ -48,15 +50,12 @@ public static Options defaultOptions() {
     }
 
     /**
-     * Produce a {@link ServiceConfig} from a raw command line args String[]
+     * Produce a {@link ServiceConfig} from command line information
      *
-     * @param args Command lines as provided in main method
+     * @param commandLine Command line object from Apache CLI
      * @return appropriate service configuration object
-     * @throws ParseException if parsing
      */
-    public static ServiceConfig fromCliArgs(final String[] args) throws ParseException {
-        final CommandLineParser serverCommandLineParser = new DefaultParser();
-        final CommandLine commandLine = serverCommandLineParser.parse(defaultOptions(), args);
+    public static ServiceConfig fromCliArgs(final CommandLine commandLine) {
 
         final Long maxNameLength = commandLine.hasOption("name-length") ? Long.valueOf(commandLine.getOptionValue("name-length")) : ServiceConfig.DEFAULT_MAXIMUM_SAMPLING_MESSAGE_NAME_SIZE;
         final Long maxContentLength = commandLine.hasOption("content-length") ? Long.valueOf(commandLine.getOptionValue("content-length")) : ServiceConfig.DEFAULT_MAXIMUM_SAMPLING_MESSAGE_CONTENT_SIZE;