more nits

src/main/java/com/hafthor/Command.java

@@ -6,7 +6,8 @@
 import java.util.List;
 
 public class Command {
-    String errorMessage, inputFile, outputFile;
+    final String inputFile, outputFile;
+    String errorMessage;
     boolean isGzip;
     List<String> fields;
 
@@ -40,7 +41,7 @@ private String parseOptions(final String[] args) {
             if ("-f".equals(arg)) {
                 if (next == null || next.isEmpty())
                     return "missing field definitions";
-                fields = Arrays.stream(next.split(",")).toList();
+                fields = Arrays.stream(next.split(",")).map(f -> f.trim()).toList();
                 i++;
             } else if ("-g".equals(arg))
                 isGzip = true;

src/main/java/com/hafthor/HelpCommand.java

@@ -7,17 +7,17 @@ protected HelpCommand() {
 
     @Override
     public int execute() {
-        System.out.println("zsvutil syntax:");
-        System.out.println("  zsvutil import/export [options] inputfile outputfile");
-        System.out.println("options:");
-        System.out.println("  -g - export: gzip the output json file / import: gunzip the input json file");
-        System.out.println("  -f [string] - fields, default is from contents of input file");
-        System.out.println("example:  # converts customers.json to customers.zsv with default options");
-        System.out.println("  zsvutil import customers.json customers.zsv");
-        System.out.println("example:  # converts customers.zsv to customers.json.gz with gzip");
-        System.out.println("  zsvutil export -g customers.zip customers.tsv.gz");
-        System.out.println("Note that, at present, zsvutil requires enough memory to hold the entire uncompressed input file in memory.");
-        System.out.println("Also note that this utility only supports the base specification of zsv and does not support the extended features.");
+        System.out.println("zsvutil syntax:\n" +
+                "  zsvutil import/export [options] inputfile outputfile\n" +
+                "options:\n" +
+                "  -g - export: gzip the output json file / import: gunzip the input json file\n" +
+                "  -f [string] - fields, default is from contents of input file\n" +
+                "example:  # converts customers.json to customers.zsv with default options\n" +
+                "  zsvutil import customers.json customers.zsv\n" +
+                "example:  # converts customers.zsv to customers.json.gz with gzip\n" +
+                "  zsvutil export -g customers.zip customers.tsv.gz\n" +
+                "Note that, at present, zsvutil requires enough memory to hold the entire uncompressed input file in memory.\n" +
+                "Also note that this utility only supports the base specification of zsv and does not support the extended features.\n");
         return 0;
     }
 }