txtbase.java

DNS Java 是java实现的DNS

// Copyright (c) 1999-2004 Brian Wellington ([e-mail])

package org.xbill.DNS;

import java.io.*;
import java.util.*;

/**
 * Implements common functionality for the many record types whose format
 * is a list of strings.
 *
 * @author Brian Wellington
 */

abstract class TXTBase extends Record {

protected List strings;

protected
TXTBase() {}

protected
TXTBase(Name name, int type, int dclass, long ttl) {
	super(name, type, dclass, ttl);
}

protected
TXTBase(Name name, int type, int dclass, long ttl, List strings) {
	super(name, type, dclass, ttl);
	if (strings == null)
		throw new IllegalArgumentException("strings must not be null");
	this.strings = new ArrayList(strings.size());
	Iterator it = strings.iterator();
	try {
		while (it.hasNext()) {
			String s = (String) it.next();
			this.strings.add(byteArrayFromString(s));
		}
	}
	catch (TextParseException e) {
		throw new IllegalArgumentException(e.getMessage());
	}
}

protected
TXTBase(Name name, int type, int dclass, long ttl, String string) {
	this(name, type, dclass, ttl, Collections.singletonList(string));
}

void
rrFromWire(DNSInput in) throws IOException {
	strings = new ArrayList(2);
	while (in.remaining() > 0) {
		byte [] b = in.readCountedString();
		strings.add(b);
	}
}

void
rdataFromString(Tokenizer st, Name origin) throws IOException {
	strings = new ArrayList(2);
	while (true) {
		Tokenizer.Token t = st.get();
		if (!t.isString())
			break;
		try {
			strings.add(byteArrayFromString(t.value));
		}
		catch (TextParseException e) { 
			throw st.exception(e.getMessage());
		}

	}
	st.unget();
}

/** converts to a String */
String
rrToString() {
	StringBuffer sb = new StringBuffer();
	Iterator it = strings.iterator();
	while (it.hasNext()) {
		byte [] array = (byte []) it.next();
		sb.append(byteArrayToString(array, true));
		if (it.hasNext())
			sb.append(" ");
	}
	return sb.toString();
}

/**
 * Returns the text strings
 * @return A list of Strings corresponding to the text strings.
 */
public List
getStrings() {
	List list = new ArrayList(strings.size());
	for (int i = 0; i < strings.size(); i++)
		list.add(byteArrayToString((byte []) strings.get(i), false));
	return list;
}

/**
 * Returns the text strings
 * @return A list of byte arrays corresponding to the text strings.
 */
public List
getStringsAsByteArrays() {
	return strings;
}

void
rrToWire(DNSOutput out, Compression c, boolean canonical) {
	Iterator it = strings.iterator();
	while (it.hasNext()) {
		byte [] b = (byte []) it.next();
		out.writeCountedString(b);
	}
}

}