вывод только определенных System.property

src/main/java/mc/server/shell/CommandService.java

@@ -5,6 +5,4 @@ import org.jline.builtins.CommandRegistry;
 public interface CommandService extends CommandRegistry {
 
     void register(String commandName, Command command);
-
-    Object execute(CommandSession session, String commandName);
 }

src/main/java/mc/server/shell/SystemPropertiesCommand.java

@@ -3,17 +3,26 @@ package mc.server.shell;
 import org.jline.builtins.Builtins.CommandInput;
 
 import java.io.PrintWriter;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Stream;
 
 public class SystemPropertiesCommand implements Command {
 
     @Override
     public void execute(CommandInput input) {
         final PrintWriter writer = input.terminal().writer();
+        Stream<Map.Entry<Object, Object>> stream = System.getProperties().entrySet().stream();
 
-        final String[] args = input.args();
-        writer.printf("args = [%s]\n", String.join(", ", args));
+        if (input.args().length > 0) {
+            final List<String> argv = Arrays.asList(input.args());
+            stream = stream.filter(entry -> {
+                //noinspection SuspiciousMethodCalls
+                return argv.contains(entry.getKey());
+            });
+        }
 
-        System.getProperties().forEach((key, value) ->
-                writer.printf("%s = %s\n", key, value.toString()));
+        stream.forEach(entry -> writer.printf("%s = %s\n", entry.getKey(), entry.getValue().toString()));
     }
 }