in src/main/java/org/apache/commons/csv/CSVFormat.java [462:471]
public Builder setDelimiter(final String delimiter) {
if (containsLineBreak(delimiter)) {
throw new IllegalArgumentException("The delimiter cannot be a line break");
}
if (delimiter.isEmpty()) {
throw new IllegalArgumentException("The delimiter cannot be empty");
}
this.delimiter = delimiter;
return this;
}