private Token
	set(int type, StringBuffer value) {
		if (type < 0)
			throw new IllegalArgumentException();
		this.type = type;
		this.value = value == null ? null : value.toString();
		return this;
	}
The value of the token, or null for tokens without values.
src/main/java/core/org/xbill/DNS/Tokenizer.java