我正在尝试开发一个系统，其中有不同的节点运行在不同的系统或在同一系统的不同端口上。
现在，所有节点都创建了一个套接字，将目标IP作为称为引导节点的特殊节点的IP。然后，节点创建自己的ServerSocket并开始侦听连接。
引导节点维护一个节点列表，并在查询时返回它们。
现在我需要的是节点必须将其IP注册到引导节点。我尝试使用cli.getInetAddress()一旦客户端连接到引导节点的ServerSocket，但这不起作用。
我需要客户端注册其PPP IP，如果可用;
否则，局域网IP(如果可用);
否则，它必须注册127.0.0.1，假设它是同一台计算机。
使用代码:
System.out.println(Inet4Address.getLocalHost().getHostAddress());
or
System.out.println(InetAddress.getLocalHost().getHostAddress());
我的PPP连接IP地址是:117.204.44.192，但上面返回我192.168.1.2
EDIT
我正在使用以下代码:
Enumeration e = NetworkInterface.getNetworkInterfaces();
while(e.hasMoreElements())
{
NetworkInterface n = (NetworkInterface) e.nextElement();
Enumeration ee = n.getInetAddresses();
while (ee.hasMoreElements())
{
InetAddress i = (InetAddress) ee.nextElement();
System.out.println(i.getHostAddress());
}
}
我能够获得所有网络接口相关的所有IP地址，但我如何区分它们?这是我得到的输出:
127.0.0.1
192.168.1.2
192.168.56.1
117.204.44.19
这是上面接受的答案的一个工作示例!
这个NetIdentity类将存储内部主机ip和本地环回。如果你在一个基于DNS的服务器上，如上所述，你可能需要添加更多的检查，或者可能进入配置文件路由。
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Enumeration;
/**
* Class that allows a device to identify itself on the INTRANET.
*
* @author Decoded4620 2016
*/
public class NetIdentity {
private String loopbackHost = "";
private String host = "";
private String loopbackIp = "";
private String ip = "";
public NetIdentity(){
try{
Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
while(interfaces.hasMoreElements()){
NetworkInterface i = interfaces.nextElement();
if(i != null){
Enumeration<InetAddress> addresses = i.getInetAddresses();
System.out.println(i.getDisplayName());
while(addresses.hasMoreElements()){
InetAddress address = addresses.nextElement();
String hostAddr = address.getHostAddress();
// local loopback
if(hostAddr.indexOf("127.") == 0 ){
this.loopbackIp = address.getHostAddress();
this.loopbackHost = address.getHostName();
}
// internal ip addresses (behind this router)
if( hostAddr.indexOf("192.168") == 0 ||
hostAddr.indexOf("10.") == 0 ||
hostAddr.indexOf("172.16") == 0 ){
this.host = address.getHostName();
this.ip = address.getHostAddress();
}
System.out.println("\t\t-" + address.getHostName() + ":" + address.getHostAddress() + " - "+ address.getAddress());
}
}
}
}
catch(SocketException e){
}
try{
InetAddress loopbackIpAddress = InetAddress.getLocalHost();
this.loopbackIp = loopbackIpAddress.getHostName();
System.out.println("LOCALHOST: " + loopbackIp);
}
catch(UnknownHostException e){
System.err.println("ERR: " + e.toString());
}
}
public String getLoopbackHost(){
return loopbackHost;
}
public String getHost(){
return host;
}
public String getIp(){
return ip;
}
public String getLoopbackIp(){
return loopbackIp;
}
}
当我运行这段代码时，我实际上得到了这样的打印结果:
Software Loopback Interface 1
-127.0.0.1:127.0.0.1 - [B@19e1023e
-0:0:0:0:0:0:0:1:0:0:0:0:0:0:0:1 - [B@7cef4e59
Broadcom 802.11ac Network Adapter
-VIKING.yourisp.com:192.168.1.142 - [B@64b8f8f4
-fe80:0:0:0:81fa:31d:21c9:85cd%wlan0:fe80:0:0:0:81fa:31d:21c9:85cd%wlan0 - [B@2db0f6b2
Microsoft Kernel Debug Network Adapter
Intel Edison USB RNDIS Device
Driver for user-mode network applications
Cisco Systems VPN Adapter for 64-bit Windows
VirtualBox Host-Only Ethernet Adapter
-VIKING:192.168.56.1 - [B@3cd1f1c8
-VIKING:fe80:0:0:0:d599:3cf0:5462:cb7%eth4 - [B@3a4afd8d
LogMeIn Hamachi Virtual Ethernet Adapter
-VIKING:25.113.118.39 - [B@1996cd68
-VIKING:2620:9b:0:0:0:0:1971:7627 - [B@3339ad8e
-VIKING:fe80:0:0:0:51bf:994d:4656:8486%eth5 - [B@555590
Bluetooth Device (Personal Area Network)
-fe80:0:0:0:4c56:8009:2bca:e16b%eth6:fe80:0:0:0:4c56:8009:2bca:e16b%eth6 - [B@3c679bde
Bluetooth Device (RFCOMM Protocol TDI)
Intel(R) Ethernet Connection (2) I218-V
-fe80:0:0:0:4093:d169:536c:7c7c%eth7:fe80:0:0:0:4093:d169:536c:7c7c%eth7 - [B@16b4a017
Microsoft Wi-Fi Direct Virtual Adapter
-fe80:0:0:0:103e:cdf0:c0ac:1751%wlan1:fe80:0:0:0:103e:cdf0:c0ac:1751%wlan1 - [B@8807e25
VirtualBox Host-Only Ethernet Adapter-HHD Software NDIS 6.0 Filter Driver-0000
VirtualBox Host-Only Ethernet Adapter-WFP Native MAC Layer LightWeight Filter-0000
VirtualBox Host-Only Ethernet Adapter-HHD Software NDIS 6.0 Filter Driver-0001
VirtualBox Host-Only Ethernet Adapter-HHD Software NDIS 6.0 Filter Driver-0002
VirtualBox Host-Only Ethernet Adapter-VirtualBox NDIS Light-Weight Filter-0000
VirtualBox Host-Only Ethernet Adapter-HHD Software NDIS 6.0 Filter Driver-0003
VirtualBox Host-Only Ethernet Adapter-QoS Packet Scheduler-0000
VirtualBox Host-Only Ethernet Adapter-HHD Software NDIS 6.0 Filter Driver-0004
VirtualBox Host-Only Ethernet Adapter-WFP 802.3 MAC Layer LightWeight Filter-0000
VirtualBox Host-Only Ethernet Adapter-HHD Software NDIS 6.0 Filter Driver-0005
Intel(R) Ethernet Connection (2) I218-V-HHD Software NDIS 6.0 Filter Driver-0000
Intel(R) Ethernet Connection (2) I218-V-WFP Native MAC Layer LightWeight Filter-0000
Intel(R) Ethernet Connection (2) I218-V-HHD Software NDIS 6.0 Filter Driver-0001
Intel(R) Ethernet Connection (2) I218-V-Shrew Soft Lightweight Filter-0000
Intel(R) Ethernet Connection (2) I218-V-HHD Software NDIS 6.0 Filter Driver-0002
Intel(R) Ethernet Connection (2) I218-V-VirtualBox NDIS Light-Weight Filter-0000
Intel(R) Ethernet Connection (2) I218-V-HHD Software NDIS 6.0 Filter Driver-0003
Intel(R) Ethernet Connection (2) I218-V-QoS Packet Scheduler-0000
Intel(R) Ethernet Connection (2) I218-V-HHD Software NDIS 6.0 Filter Driver-0004
Intel(R) Ethernet Connection (2) I218-V-WFP 802.3 MAC Layer LightWeight Filter-0000
Intel(R) Ethernet Connection (2) I218-V-HHD Software NDIS 6.0 Filter Driver-0005
Broadcom 802.11ac Network Adapter-WFP Native MAC Layer LightWeight Filter-0000
Broadcom 802.11ac Network Adapter-Virtual WiFi Filter Driver-0000
Broadcom 802.11ac Network Adapter-Native WiFi Filter Driver-0000
Broadcom 802.11ac Network Adapter-HHD Software NDIS 6.0 Filter Driver-0003
Broadcom 802.11ac Network Adapter-Shrew Soft Lightweight Filter-0000
Broadcom 802.11ac Network Adapter-HHD Software NDIS 6.0 Filter Driver-0004
Broadcom 802.11ac Network Adapter-VirtualBox NDIS Light-Weight Filter-0000
Broadcom 802.11ac Network Adapter-HHD Software NDIS 6.0 Filter Driver-0005
Broadcom 802.11ac Network Adapter-QoS Packet Scheduler-0000
Broadcom 802.11ac Network Adapter-HHD Software NDIS 6.0 Filter Driver-0006
Broadcom 802.11ac Network Adapter-WFP 802.3 MAC Layer LightWeight Filter-0000
Broadcom 802.11ac Network Adapter-HHD Software NDIS 6.0 Filter Driver-0007
Microsoft Wi-Fi Direct Virtual Adapter-WFP Native MAC Layer LightWeight Filter-0000
Microsoft Wi-Fi Direct Virtual Adapter-Native WiFi Filter Driver-0000
Microsoft Wi-Fi Direct Virtual Adapter-HHD Software NDIS 6.0 Filter Driver-0002
Microsoft Wi-Fi Direct Virtual Adapter-Shrew Soft Lightweight Filter-0000
Microsoft Wi-Fi Direct Virtual Adapter-HHD Software NDIS 6.0 Filter Driver-0003
Microsoft Wi-Fi Direct Virtual Adapter-VirtualBox NDIS Light-Weight Filter-0000
Microsoft Wi-Fi Direct Virtual Adapter-HHD Software NDIS 6.0 Filter Driver-0004
Microsoft Wi-Fi Direct Virtual Adapter-QoS Packet Scheduler-0000
Microsoft Wi-Fi Direct Virtual Adapter-HHD Software NDIS 6.0 Filter Driver-0005
Microsoft Wi-Fi Direct Virtual Adapter-WFP 802.3 MAC Layer LightWeight Filter-0000
Microsoft Wi-Fi Direct Virtual Adapter-HHD Software NDIS 6.0 Filter Driver-0006
为了我的使用，我设置了一个Upnp服务器，它有助于理解我正在寻找的“模式”。返回的对象包括以太网适配器、网络适配器、虚拟网络适配器、驱动程序和VPN客户端适配器。也不是所有东西都有地址。所以你会想要跳过那些不需要的接口对象。
您还可以将此添加到当前NetworkInterface i的循环中
while(interfaces.hasMoreElements()){
Enumeration<InetAddress> addresses = i.getInetAddresses();
System.out.println(i.getDisplayName());
System.out.println("\t- name:" + i.getName());
System.out.println("\t- idx:" + i.getIndex());
System.out.println("\t- max trans unit (MTU):" + i.getMTU());
System.out.println("\t- is loopback:" + i.isLoopback());
System.out.println("\t- is PPP:" + i.isPointToPoint());
System.out.println("\t- isUp:" + i.isUp());
System.out.println("\t- isVirtual:" + i.isVirtual());
System.out.println("\t- supportsMulticast:" + i.supportsMulticast());
}
你会在输出中看到类似这样的信息:
Software Loopback Interface 1
- name:lo
- idx:1
- max trans unit (MTU):-1
- is loopback:true
- is PPP:false
- isUp:true
- isVirtual:false
- supportsMulticast:true
-ADRESS: [127.0.0.1(VIKING-192.168.56.1)]127.0.0.1:127.0.0.1 - [B@19e1023e
-ADRESS: [0:0:0:0:0:0:0:1(VIKING-192.168.56.1)]0:0:0:0:0:0:0:1:0:0:0:0:0:0:0:1 - [B@7cef4e59
Broadcom 802.11ac Network Adapter
- name:wlan0
- idx:2
- max trans unit (MTU):1500
- is loopback:false
- is PPP:false
- isUp:true
- isVirtual:false
- supportsMulticast:true
-ADRESS: [VIKING.monkeybrains.net(VIKING-192.168.56.1)]VIKING.monkeybrains.net:192.168.1.142 - [B@64b8f8f4
-ADRESS: [fe80:0:0:0:81fa:31d:21c9:85cd%wlan0(VIKING-192.168.56.1)]fe80:0:0:0:81fa:31d:21c9:85cd%wlan0:fe80:0:0:0:81fa:31d:21c9:85cd%wlan0 - [B@2db0f6b2
Microsoft Kernel Debug Network Adapter
- name:eth0
- idx:3
- max trans unit (MTU):-1
- is loopback:false
- is PPP:false
- isUp:false
- isVirtual:false
- supportsMulticast:true
在这里发布来自https://issues.apache.org/jira/browse/JCS-40的测试IP歧义变通代码(InetAddress.getLocalHost()在Linux系统上是歧义的):
/**
* Returns an <code>InetAddress</code> object encapsulating what is most likely the machine's LAN IP address.
* <p/>
* This method is intended for use as a replacement of JDK method <code>InetAddress.getLocalHost</code>, because
* that method is ambiguous on Linux systems. Linux systems enumerate the loopback network interface the same
* way as regular LAN network interfaces, but the JDK <code>InetAddress.getLocalHost</code> method does not
* specify the algorithm used to select the address returned under such circumstances, and will often return the
* loopback address, which is not valid for network communication. Details
* <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4665037">here</a>.
* <p/>
* This method will scan all IP addresses on all network interfaces on the host machine to determine the IP address
* most likely to be the machine's LAN address. If the machine has multiple IP addresses, this method will prefer
* a site-local IP address (e.g. 192.168.x.x or 10.10.x.x, usually IPv4) if the machine has one (and will return the
* first site-local address if the machine has more than one), but if the machine does not hold a site-local
* address, this method will return simply the first non-loopback address found (IPv4 or IPv6).
* <p/>
* If this method cannot find a non-loopback address using this selection algorithm, it will fall back to
* calling and returning the result of JDK method <code>InetAddress.getLocalHost</code>.
* <p/>
*
* @throws UnknownHostException If the LAN address of the machine cannot be found.
*/
private static InetAddress getLocalHostLANAddress() throws UnknownHostException {
try {
InetAddress candidateAddress = null;
// Iterate all NICs (network interface cards)...
for (Enumeration ifaces = NetworkInterface.getNetworkInterfaces(); ifaces.hasMoreElements();) {
NetworkInterface iface = (NetworkInterface) ifaces.nextElement();
// Iterate all IP addresses assigned to each card...
for (Enumeration inetAddrs = iface.getInetAddresses(); inetAddrs.hasMoreElements();) {
InetAddress inetAddr = (InetAddress) inetAddrs.nextElement();
if (!inetAddr.isLoopbackAddress()) {
if (inetAddr.isSiteLocalAddress()) {
// Found non-loopback site-local address. Return it immediately...
return inetAddr;
}
else if (candidateAddress == null) {
// Found non-loopback address, but not necessarily site-local.
// Store it as a candidate to be returned if site-local address is not subsequently found...
candidateAddress = inetAddr;
// Note that we don't repeatedly assign non-loopback non-site-local addresses as candidates,
// only the first. For subsequent iterations, candidate will be non-null.
}
}
}
}
if (candidateAddress != null) {
// We did not find a site-local address, but we found some other non-loopback address.
// Server might have a non-site-local address assigned to its NIC (or it might be running
// IPv6 which deprecates the "site-local" concept).
// Return this non-loopback candidate address...
return candidateAddress;
}
// At this point, we did not find a non-loopback address.
// Fall back to returning whatever InetAddress.getLocalHost() returns...
InetAddress jdkSuppliedAddress = InetAddress.getLocalHost();
if (jdkSuppliedAddress == null) {
throw new UnknownHostException("The JDK InetAddress.getLocalHost() method unexpectedly returned null.");
}
return jdkSuppliedAddress;
}
catch (Exception e) {
UnknownHostException unknownHostException = new UnknownHostException("Failed to determine LAN address: " + e);
unknownHostException.initCause(e);
throw unknownHostException;
}
}
你的计算机可以有多个网络接口，每个网络接口有多个inetaddress。如果过滤掉任何本地地址，则提醒的地址是非本地地址，其中可以有一个、没有或多个。
不幸的是，Java中的网络API仍然使用(旧的)枚举而不是迭代器和流，我们可以通过将它们包装为流来进行对抗。所以我们要做的就是
所有网络接口及其地址的流，以及
过滤掉本地的
代码:
private Stream<InetAddress> getNonLocalIpAddresses() throws IOException {
return enumerationAsStream(NetworkInterface.getNetworkInterfaces())
.flatMap(networkInterface -> enumerationAsStream(networkInterface.getInetAddresses()))
.filter(inetAddress -> !inetAddress.isAnyLocalAddress())
.filter(inetAddress -> !inetAddress.isSiteLocalAddress())
.filter(inetAddress -> !inetAddress.isLoopbackAddress())
.filter(inetAddress -> !inetAddress.isLinkLocalAddress());
}
在我的机器上，这目前返回两个IPv6地址。
要获得这些inetaddress中的第一个:
private String getMyIp() throws IOException {
return getNonLocalIpAddresses()
.map(InetAddress::getHostAddress)
.findFirst()
.orElseThrow(NoSuchElementException::new);
}
将枚举包装为流的方法:
public static <T> Stream<T> enumerationAsStream(Enumeration<T> e) {
return StreamSupport.stream(
Spliterators.spliteratorUnknownSize(
new Iterator<>() {
public T next() { return e.nextElement(); }
public boolean hasNext() { return e.hasMoreElements(); }
}, Spliterator.ORDERED), false);
}
