/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file to you 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 org.jboss.netty.util;
import org.junit.Ignore;
import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
/**
*/
@Ignore
public final class TestUtil {
private static final InetAddress LOCALHOST;
static {
InetAddress localhost;
try {
localhost = InetAddress.getLocalHost();
validateHost(localhost);
} catch (IOException e) {
// The default local host names did not work. Try hard-coded IPv4 address.
try {
localhost = InetAddress.getByAddress(new byte[] { 127, 0, 0, 1 });
validateHost(localhost);
} catch (IOException e1) {
// The hard-coded IPv4 address did not work. Try hard coded IPv6 address.
try {
localhost = InetAddress.getByAddress(new byte[] { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 });
validateHost(localhost);
} catch (IOException e2) {
throw new Error("Failed to resolve localhost - incorrect network configuration?", e2);
}
}
}
LOCALHOST = localhost;
}
private static void validateHost(InetAddress host) throws IOException {
ServerSocket ss = null;
Socket s1 = null;
Socket s2 = null;
try {
ss = new ServerSocket();
ss.setReuseAddress(false);
ss.bind(new InetSocketAddress(host, 0));
s1 = new Socket(host, ss.getLocalPort());
s2 = ss.accept();
} finally {
if (s2 != null) {
try {
s2.close();
} catch (IOException e) {
// Ignore
}
}
if (s1 != null) {
try {
s1.close();
} catch (IOException e) {
// Ignore
}
}
if (ss != null) {
try {
ss.close();
} catch (IOException e) {
// Ignore
}
}
}
}
public static InetAddress getLocalHost() {
// We cache this because some machine takes almost forever to return
// from InetAddress.getLocalHost(). I think it's due to the incorrect
// /etc/hosts or /etc/resolve.conf.
return LOCALHOST;
}
private static final int START_PORT = 32768;
private static final int END_PORT = 65536;
private static final int NUM_CANDIDATES = END_PORT - START_PORT;
private static final List<Integer> PORTS = new ArrayList<Integer>();
private static Iterator<Integer> portIterator;
static {
for (int i = START_PORT; i < END_PORT; i ++) {
PORTS.add(i);
}
Collections.shuffle(PORTS);
}
private static int nextCandidatePort() {
if (portIterator == null || !portIterator.hasNext()) {
portIterator = PORTS.iterator();
}
return portIterator.next();
}
/**
* Return a free port which can be used to bind to
*
* @return port
*/
public static int getFreePort() {
for (int i = 0; i < NUM_CANDIDATES; i ++) {
int port = nextCandidatePort();
try {
// Ensure it is possible to bind on both wildcard and loopback.
ServerSocket ss;
ss = new ServerSocket();
ss.setReuseAddress(false);
ss.bind(new InetSocketAddress(port));
ss.close();
ss = new ServerSocket();
ss.setReuseAddress(false);
ss.bind(new InetSocketAddress(LOCALHOST, port));
ss.close();
return port;
} catch (IOException e) {
// ignore
}
}
throw new RuntimeException("unable to find a free port");
}
private TestUtil() {
// Unused
}
}