Program: 57995
Project: 57995
Buggy source:
@Override public boolean onCommand(final CommandCaller caller,final String[] args){
  if (args.length == 1) {
    final String arg=args[0].toLowerCase();
    final PlotId id=getId(arg);
    if (id != null) {
      caller.message("String_Node_Str");
      return false;
    }
    final UUID uuid=UUIDHandler.getUUID(args[0]);
    if (uuid != null) {
      caller.message("String_Node_Str" + args[0] + "String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    caller.message(C.PURGE_SYNTAX);
    return false;
  }
  if (args.length != 2) {
    caller.message(C.PURGE_SYNTAX);
    return false;
  }
  final String worldname=args[1];
  if (!PS.get().getAllPlotsRaw().containsKey(worldname)) {
    caller.message("String_Node_Str");
    return false;
  }
  final String arg=args[0].toLowerCase();
  final PlotId id=getId(arg);
  if (id != null) {
    final HashSet<Integer> ids=new HashSet<Integer>();
    final int DBid=DBFunc.getId(worldname,id);
    if (DBid != Integer.MAX_VALUE) {
      ids.add(DBid);
    }
    DBFunc.purgeIds(worldname,ids);
    return finishPurge(DBid == Integer.MAX_VALUE ? 1 : 0);
  }
  if (arg.equals("String_Node_Str")) {
    final Set<PlotId> ids=PS.get().getPlots(worldname).keySet();
    int length=ids.size();
    if (length == 0) {
      return MainUtil.sendMessage(null,"String_Node_Str");
    }
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  if (arg.equals("String_Node_Str")) {
    final Collection<Plot> plots=PS.get().getPlots(worldname).values();
    final Set<PlotId> ids=new HashSet<>();
    for (    final Plot plot : plots) {
      if (plot.owner != null) {
        final String name=UUIDHandler.getName(plot.owner);
        if (name == null) {
          ids.add(plot.id);
        }
      }
    }
    int length=ids.size();
    if (length == 0) {
      return MainUtil.sendMessage(null,"String_Node_Str");
    }
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  if (arg.equals("String_Node_Str")) {
    final Collection<Plot> plots=PS.get().getPlots(worldname).values();
    final Set<PlotId> ids=new HashSet<>();
    for (    final Plot plot : plots) {
      if (plot.owner == null) {
        ids.add(plot.id);
      }
    }
    int length=ids.size();
    if (length == 0) {
      return MainUtil.sendMessage(null,"String_Node_Str");
    }
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  final UUID uuid=UUIDHandler.getUUID(args[0]);
  if (uuid != null) {
    final Set<Plot> plots=PS.get().getPlots(worldname,uuid);
    final Set<PlotId> ids=new HashSet<>();
    for (    final Plot plot : plots) {
      ids.add(plot.id);
    }
    int length=ids.size();
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  caller.message(C.PURGE_SYNTAX);
  return false;
}

Fixed version (ground truth):
@Override public boolean onCommand(final CommandCaller caller,final String[] args){
  if (args.length == 1) {
    final String arg=args[0].toLowerCase();
    final PlotId id=getId(arg);
    if (id != null) {
      caller.message("String_Node_Str");
      return false;
    }
    final UUID uuid=UUIDHandler.getUUID(args[0],null);
    if (uuid != null) {
      caller.message("String_Node_Str" + args[0] + "String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    if (arg.equals("String_Node_Str")) {
      caller.message("String_Node_Str");
      return false;
    }
    caller.message(C.PURGE_SYNTAX);
    return false;
  }
  if (args.length != 2) {
    caller.message(C.PURGE_SYNTAX);
    return false;
  }
  final String worldname=args[1];
  if (!PS.get().getAllPlotsRaw().containsKey(worldname)) {
    caller.message("String_Node_Str");
    return false;
  }
  final String arg=args[0].toLowerCase();
  final PlotId id=getId(arg);
  if (id != null) {
    final HashSet<Integer> ids=new HashSet<Integer>();
    final int DBid=DBFunc.getId(worldname,id);
    if (DBid != Integer.MAX_VALUE) {
      ids.add(DBid);
    }
    DBFunc.purgeIds(worldname,ids);
    return finishPurge(DBid == Integer.MAX_VALUE ? 1 : 0);
  }
  if (arg.equals("String_Node_Str")) {
    final Set<PlotId> ids=PS.get().getPlots(worldname).keySet();
    int length=ids.size();
    if (length == 0) {
      return MainUtil.sendMessage(null,"String_Node_Str");
    }
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  if (arg.equals("String_Node_Str")) {
    final Collection<Plot> plots=PS.get().getPlots(worldname).values();
    final Set<PlotId> ids=new HashSet<>();
    for (    final Plot plot : plots) {
      if (plot.owner != null) {
        final String name=UUIDHandler.getName(plot.owner);
        if (name == null) {
          ids.add(plot.id);
        }
      }
    }
    int length=ids.size();
    if (length == 0) {
      return MainUtil.sendMessage(null,"String_Node_Str");
    }
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  if (arg.equals("String_Node_Str")) {
    final Collection<Plot> plots=PS.get().getPlots(worldname).values();
    final Set<PlotId> ids=new HashSet<>();
    for (    final Plot plot : plots) {
      if (plot.owner == null) {
        ids.add(plot.id);
      }
    }
    int length=ids.size();
    if (length == 0) {
      return MainUtil.sendMessage(null,"String_Node_Str");
    }
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  final UUID uuid=UUIDHandler.getUUID(args[0],null);
  if (uuid != null) {
    final Set<Plot> plots=PS.get().getPlots(worldname,uuid);
    final Set<PlotId> ids=new HashSet<>();
    for (    final Plot plot : plots) {
      ids.add(plot.id);
    }
    int length=ids.size();
    DBFunc.purge(worldname,ids);
    return finishPurge(length);
  }
  caller.message(C.PURGE_SYNTAX);
  return false;
}