/*
* Copyright (c) 2011-2018 Pivotal Software Inc, All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package reactor.netty.tcp;
import java.net.
Inet4Address;
import java.net.
Inet6Address;
import java.net.
InetAddress;
import java.net.
InetSocketAddress;
import java.net.
UnknownHostException;
import javax.annotation.
Nullable;
import io.netty.util.
NetUtil;
/**
* Internal class that creates unresolved or resolved InetSocketAddress instances
*
* Numeric IPv4 and IPv6 addresses will be detected and parsed by using Netty's
* {@link NetUtil#createByteArrayFromIpAddressString} utility method and the
* InetSocketAddress instances will created in a way that these instances are resolved
* initially. This removes the need to do unnecessary reverse DNS lookups.
*
*/
public class
InetSocketAddressUtil {
/**
* Creates unresolved InetSocketAddress. Numeric IP addresses will be detected and
* resolved.
*
* @param hostname ip-address or hostname
* @param port port number
* @return InetSocketAddress for given parameters
*/
public static
InetSocketAddress createUnresolved(
String hostname, int
port) {
return
createInetSocketAddress(
hostname,
port, false);
}
/**
* Creates InetSocketAddress that is always resolved. Numeric IP addresses will be
* detected and resolved without doing reverse DNS lookups.
*
* @param hostname ip-address or hostname
* @param port port number
* @return InetSocketAddress for given parameters
*/
public static
InetSocketAddress createResolved(
String hostname, int
port) {
return
createInetSocketAddress(
hostname,
port, true);
}
/**
* Creates InetSocketAddress instance. Numeric IP addresses will be detected and
* resolved without doing reverse DNS lookups.
*
* @param hostname ip-address or hostname
* @param port port number
* @param resolve when true, resolve given hostname at instance creation time
* @return InetSocketAddress for given parameters
*/
public static
InetSocketAddress createInetSocketAddress(
String hostname, int
port,
boolean
resolve) {
InetSocketAddress inetAddressForIpString =
createForIpString(
hostname,
port);
if (
inetAddressForIpString != null) {
return
inetAddressForIpString;
}
else {
return
resolve ? new
InetSocketAddress(
hostname,
port)
:
InetSocketAddress.
createUnresolved(
hostname,
port);
}
}
@
Nullable
private static
InetSocketAddress createForIpString(
String hostname, int
port) {
InetAddress inetAddressForIpString =
attemptParsingIpString(
hostname);
if (
inetAddressForIpString != null) {
return new
InetSocketAddress(
inetAddressForIpString,
port);
}
return null;
}
/**
* Replaces an unresolved InetSocketAddress with a resolved instance in the case that
* the passed address is unresolved.
*
* @param inetSocketAddress socket address instance to process
* @return resolved instance with same host string and port
*/
public static
InetSocketAddress replaceWithResolved(
InetSocketAddress inetSocketAddress) {
if (!
inetSocketAddress.
isUnresolved()) {
return
inetSocketAddress;
}
inetSocketAddress =
replaceUnresolvedNumericIp(
inetSocketAddress);
if (!
inetSocketAddress.
isUnresolved()) {
return
inetSocketAddress;
}
else {
return new
InetSocketAddress(
inetSocketAddress.
getHostString(),
inetSocketAddress.
getPort());
}
}
/**
* Replaces an unresolved InetSocketAddress with a resolved instance in the case that
* the passed address is a numeric IP address (both IPv4 and IPv6 are supported).
*
* @param inetSocketAddress socket address instance to process
* @return processed socket address instance
*/
public static
InetSocketAddress replaceUnresolvedNumericIp(
InetSocketAddress inetSocketAddress) {
if (!
inetSocketAddress.
isUnresolved()) {
return
inetSocketAddress;
}
InetSocketAddress inetAddressForIpString =
createForIpString(
inetSocketAddress.
getHostString(),
inetSocketAddress.
getPort());
if (
inetAddressForIpString != null) {
return
inetAddressForIpString;
}
else {
return
inetSocketAddress;
}
}
@
Nullable
private static
InetAddress attemptParsingIpString(
String hostname) {
byte[]
ipAddressBytes =
NetUtil.
createByteArrayFromIpAddressString(
hostname);
if (
ipAddressBytes != null) {
try {
if (
ipAddressBytes.length == 4) {
return
Inet4Address.
getByAddress(
ipAddressBytes);
}
else {
return
Inet6Address.
getByAddress(null,
ipAddressBytes, -1);
}
}
catch (
UnknownHostException e) {
throw new
RuntimeException(
e); // Should never happen
}
}
return null;
}
}