net.sf.jasperreports.phantomjs.InetUtil.java Source code

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Here is the source code for net.sf.jasperreports.phantomjs.InetUtil.java

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/*
 * JasperReports - Free Java Reporting Library.
 * Copyright (C) 2001 - 2019 TIBCO Software Inc. All rights reserved.
 * http://www.jaspersoft.com
 *
 * Unless you have purchased a commercial license agreement from Jaspersoft,
 * the following license terms apply:
 *
 * This program is part of JasperReports.
 *
 * JasperReports is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * JasperReports is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with JasperReports. If not, see <http://www.gnu.org/licenses/>.
 */
package net.sf.jasperreports.phantomjs;

import java.io.IOException;
import java.net.Inet4Address;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.ServerSocket;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Enumeration;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import net.sf.jasperreports.engine.JRRuntimeException;

/**
 * @author Lucian Chirita (lucianc@users.sourceforge.net)
 */
public class InetUtil {
    private static final Log log = LogFactory.getLog(InetUtil.class);

    public static Inet4Address getIPv4Loopback() {
        InetAddress loopbackAddress = InetAddress.getLoopbackAddress();
        //the phantomjs web server module only works with IPv4
        if (loopbackAddress instanceof Inet4Address) {
            return (Inet4Address) loopbackAddress;
        }

        try {
            InetAddress[] addresses = InetAddress.getAllByName(loopbackAddress.getHostName());
            for (InetAddress inetAddress : addresses) {
                if (inetAddress instanceof Inet4Address) {
                    return (Inet4Address) inetAddress;
                }
            }
        } catch (UnknownHostException e) {
            log.warn("Error while determining loopback addresses for " + loopbackAddress.getHostName(), e);
        }

        try {
            //keep looking for a IPv4 loopback address
            for (Enumeration<NetworkInterface> itfs = NetworkInterface.getNetworkInterfaces(); itfs
                    .hasMoreElements();) {
                NetworkInterface itf = itfs.nextElement();
                if (itf.isLoopback()) {
                    for (Enumeration<InetAddress> addresses = itf.getInetAddresses(); addresses
                            .hasMoreElements();) {
                        InetAddress address = addresses.nextElement();
                        if (address instanceof Inet4Address) {
                            return (Inet4Address) address;
                        }
                    }
                }
            }
        } catch (SocketException e) {
            log.warn("Error while listing network interfaces", e);
        }

        return null;
    }

    public static int getAvailablePort() {
        try (ServerSocket socket = new ServerSocket(0)) {
            int port = socket.getLocalPort();
            if (log.isDebugEnabled()) {
                log.debug("found available port " + port);
            }
            return port;
        } catch (IOException e) {
            throw new JRRuntimeException(e);
        }

    }

}