LocalHostService.java

/**
 * 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;

/**
 * 获取真实本机网络的实现类.
 * 
 * 
 */
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读取顺序：参数 -> 环境变量 -> 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
	}
	
	/**
	 * 获取本机Host名称.
	 * 
	 * @return 本机Host名称
	 */
	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();  
  
    }  
}