CommandCompleter.java

package org.batfish.client;

import static jline.internal.Preconditions.checkNotNull;

import java.util.List;
import java.util.SortedSet;
import java.util.TreeSet;

import jline.console.completer.Completer;

public class CommandCompleter implements Completer {

   private final SortedSet<String> commandStrs = new TreeSet<>();

   public CommandCompleter() {
      commandStrs.addAll(Command.getNameMap().keySet());
   }

   @Override
   public int complete(String buffer, int cursor,
         List<CharSequence> candidates) {
      checkNotNull(candidates);

      if (buffer == null) {
         candidates.addAll(commandStrs);
      }
      else {
         String trimmedBuffer = buffer.trim();

         for (String match : commandStrs.tailSet(buffer)) {
            if (!match.startsWith(trimmedBuffer)) {
               break;
            }

            candidates.add(match);
         }
      }

      // if the match was unique and the complete command was specified, print
      // the command usage
      if (candidates.size() == 1 && candidates.get(0).equals(buffer)) {
         candidates.clear();
         candidates.add(buffer + " " + Command.getUsageMap()
               .get(Command.getNameMap().get(buffer)).getFirst());
      }

      return candidates.isEmpty() ? -1 : 0;
   }
}