Remove last character of a StringBuilder?

java, stringbuilder

Solution

Others have pointed out the `deleteCharAt` method, but here's another alternative approach:

String prefix = "";
for (String serverId : serverIds) {
  sb.append(prefix);
  prefix = ",";
  sb.append(serverId);
}

Alternatively, use the `Joiner` class from Guava :)

As of Java 8, `StringJoiner` is part of the standard JRE.

Problem

When you have to loop through a collection and make a string of each data separated by a delimiter, you always end up with an extra delimiter at the end, e.g. ``` for (String serverId : serverIds) { sb.append(serverId); sb.append(","); } ``` Gives something like : serverId_1, serverId_2, serverId_3, I would like to delete the last character in the StringBuilder (without converting it because I still need it after this loop).

Original source

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