Short-circuit option -R if --help|-h|-? is used

Author: idodeclare

opengrok-indexer/src/main/java/org/opengrok/indexer/index/Indexer.java

@@ -20,7 +20,7 @@
 /*
  * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * Portions Copyright 2011 Jens Elkner.
- * Portions Copyright (c) 2017-2018, Chris Fraire <cfraire@me.com>.
+ * Portions Copyright (c) 2017-2019, Chris Fraire <cfraire@me.com>.
  */
 package org.opengrok.indexer.index;
 
@@ -92,6 +92,10 @@ public final class Indexer {
     public static final char PATH_SEPARATOR ='/';
     public static String PATH_SEPARATOR_STRING =Character.toString(PATH_SEPARATOR);
 
+    private static final String HELP_OPT_1 = "--help";
+    private static final String HELP_OPT_2 = "-?";
+    private static final String HELP_OPT_3 = "-h";
+
     private static final Indexer index = new Indexer();
     private static Configuration cfg = null;
     private static boolean checkIndexVersion = false;
@@ -402,7 +406,7 @@ public static WebAddress parseWebAddress(String webAddr) {
      * @throws ParseException if parsing failed
      */
     public static String[] parseOptions(String[] argv) throws ParseException {
-        String[] usage = {"--help"};
+        String[] usage = {HELP_OPT_1};
         String program = "opengrok.jar";
         final String[] ON_OFF = {ON, OFF};
         final String[] REMOTE_REPO_CHOICES = {ON, OFF, DIRBASED, UIONLY};
@@ -413,10 +417,19 @@ public static String[] parseOptions(String[] argv) throws ParseException {
             status = 1;
         }
 
+        /*
+         * Pre-match any of the --help options so that some possible exception-
+         * generating args handlers (e.g. -R) can be short-circuited.
+         */
+        help = Arrays.stream(argv).anyMatch(s -> HELP_OPT_1.equals(s) ||
+                HELP_OPT_2.equals(s) || HELP_OPT_3.equals(s));
+
         OptionParser configure = OptionParser.scan(parser -> {
             parser.on("-R configPath").Do(cfgFile -> {
                 try {
-                    cfg = Configuration.read(new File((String)cfgFile));
+                    if (!help) {
+                        cfg = Configuration.read(new File((String) cfgFile));
+                    }
                 } catch(IOException e) {
                     die(e.getMessage());
                 }
@@ -430,7 +443,8 @@ public static String[] parseOptions(String[] argv) throws ParseException {
             parser.setPrologue(
                 String.format("\nUsage: java -jar %s [options] [subDir1 [...]]\n", program));
 
-            parser.on("-?", "-h", "--help", "Display this usage summary.").Do(v -> {
+            parser.on(HELP_OPT_3, Indexer.HELP_OPT_2, HELP_OPT_1,
+                    "Display this usage summary.").Do(v -> {
                 help = true;
                 helpUsage = parser.getUsage();
             });