command.replaceAll("$player", player.getName()); | Bukkit

Question

I'm working on a system there connect my website with my Minecraft Server through a JavaPlugin! But I had meet some problem when I try to replace $player in a String with my Minecraft Players Ing Name, please help :)

ResultSet results = statement.executeQuery();
if(results.next()) {
    String command = ""+results.getString(2);
    String newcmd = ""+command.replaceAll("\b$player\b", ""+player.getName());
    System.out.println(newcmd);
    player.sendMessage("\u00A75SpaceStore \u00A78\u00A7l| \u00A72Code Activated!");
}

String command is the same as "give $player stone"

Output

give $player stone

You have to escape the $ sign it is a special character in regex — Jens, Sep 01 '19 at 10:20
Try `command.replaceAll("\b\\$player\b", ""+player.getName());` — seenukarthi, Sep 01 '19 at 10:21
@KarthikeyanVaithilingam My Variable "command" is "give $player stone" and that with ``\b`` was something i saw on a tutorial — Mads Lundgren Larsen, Sep 01 '19 at 10:27
Thx for your help guys i had solved it now, i should only change ``$`` to another sign like ``@`` and then it work, thx for your help and time. :) — Mads Lundgren Larsen, Sep 01 '19 at 10:31
You can also use `String::replace` instead of `String::replaceAll`. Former doesn't treat its first parameter like it's a regular expression, like the latter does. — M. Prokhorov, Sep 01 '19 at 10:36
As @Jens said you can use `String.format("give %s stone",player.getName())` — seenukarthi, Sep 01 '19 at 10:37
Mads - instead of just relying on tutorials, you should lookup the javadocs for the respective classes and methods and carefully read them. Stuff in tutorials tends to be "dumbed down" ... and glosses over important details that a programmer needs to know. — Stephen C, Sep 01 '19 at 10:47

score 0 · Answer 1 · answered Sep 01 '19 at 10:51

First, you need to use double backslashes to specify the word boundary as stated in Backslashes, escapes, and quoting here: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html

It is therefore necessary to double backslashes in string literals that represent regular expressions to protect them from interpretation by the Java bytecode compiler.

Second, there's no word boundary between the space and $ symbol as they are both non-word symbols, you can read the explanation of the word boundary here: What is a word boundary in regexes?

The proper syntax will be System.out.println(s.replaceAll("\\$player\\b", "user1"));

Try this code:

public static void main(String[] args) {
  String s = "give $player stone";
  System.out.println(s.replaceAll("\\b\\$player\\b", "user1"));
  System.out.println(s.replaceAll("\\$player\\b", "user1"));
}

It outputs:

give $player stone
give user1 stone

command.replaceAll("$player", player.getName()); | Bukkit

1 Answers1