com.vip.saturn.job.utils.LocalHostService.java Source code

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/**
 * Copyright 2016 vip.com.
 * <p>
 * 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.
 * </p>
 */

package com.vip.saturn.job.utils;

import java.net.Inet6Address;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.UnknownHostException;
import java.util.Enumeration;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.StringUtils;

import com.google.common.base.Strings;

/**
 * ?.
 * 
 * 
 */
public class LocalHostService {

    private static final String IP_REGEX = "^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\."
            + "(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."
            + "(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."
            + "(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$";
    public static volatile String cachedIpAddress;

    /** for inner test */
    private static volatile String cachedHostName;

    private static final String ERROR_HOSTNAME = "GET_HOSTNAME_ERROR";
    /**
     * ip??? -> ?? -> bond0 -> eth0
     */
    static {
        cachedIpAddress = System.getProperty("VIP_SATURN_RUNNING_IP", System.getenv("VIP_SATURN_RUNNING_IP"));
        cachedHostName = System.getProperty("VIP_SATURN_RUNNING_HOSTNAME",
                System.getenv("VIP_SATURN_RUNNING_HOSTNAME"));
        if (StringUtils.isEmpty(cachedIpAddress)) {
            try {
                InetAddress inetAddress = InetAddress.getLocalHost();
                if (inetAddress.getHostAddress() == null || "127.0.0.1".equals(inetAddress.getHostAddress())) {
                    NetworkInterface ni = NetworkInterface.getByName("bond0");
                    if (ni == null) {
                        ni = NetworkInterface.getByName("eth0");
                    }
                    if (ni == null) {
                        throw new Exception(
                                "wrong with get ip cause by could not read any info from local host, bond0 and eth0");
                    }

                    Enumeration<InetAddress> ips = ni.getInetAddresses();
                    while (ips.hasMoreElements()) {
                        InetAddress nextElement = ips.nextElement();
                        if (!"127.0.0.1".equals(nextElement.getHostAddress())
                                && !(nextElement instanceof Inet6Address)
                                && !nextElement.getHostAddress().contains(":")) {
                            inetAddress = nextElement;
                            break;
                        }
                    }
                }
                cachedIpAddress = inetAddress.getHostAddress();
            } catch (Throwable e) {//NOSONAR
                System.err.println("getCachedAddressException:" + e.toString());//NOSONAR
                System.exit(-1);
            }
        } else {
            if (!isIpv4(cachedIpAddress)) {
                System.err.println("IP address " + cachedIpAddress + " is illegal. System is shutting down.");//NOSONAR
                System.exit(-1);
            }
        }
        System.out.println("Done initial localhostip: " + cachedIpAddress);//NOSONAR
    }

    /**
     * ?Host??.
     * 
     * @return Host??
     */
    public static String getHostName() {
        if (!Strings.isNullOrEmpty(cachedHostName)) {
            return cachedHostName;
        } else {
            try {
                cachedHostName = InetAddress.getLocalHost().getHostName();
            } catch (UnknownHostException e) {//NOSONAR
                e.printStackTrace();//NOSONAR
                return ERROR_HOSTNAME;
            }
            return cachedHostName;
        }
    }

    // for test only!
    @Deprecated
    public static void setCachedIpAddress(String ip) {
        cachedIpAddress = ip;
    }

    // for test only!
    @Deprecated
    public static void setCachedHostName(String hostName) {
        cachedHostName = hostName;
    }

    private static boolean isIpv4(String ipAddress) {
        Pattern pattern = Pattern.compile(IP_REGEX);
        Matcher matcher = pattern.matcher(ipAddress);
        return matcher.matches();

    }
}