public final class NetworkInterface extends Object
Modifier and Type | Method | Description |
---|---|---|
boolean |
equals |
Compares this object against the specified object. |
static NetworkInterface |
getByIndex |
Get a network interface given its index. |
static NetworkInterface |
getByInetAddress |
Convenience method to search for a network interface that has the specified Internet Protocol (IP) address bound to it. |
static NetworkInterface |
getByName |
Searches for the network interface with the specified name. |
String |
getDisplayName() |
Get the display name of this network interface. |
byte[] |
getHardwareAddress() |
Returns the hardware address (usually MAC) of the interface if it has one and if it can be accessed given the current privileges. |
int |
getIndex() |
Returns the index of this network interface. |
Enumeration |
getInetAddresses() |
Get an Enumeration with all or a subset of the InetAddresses bound to this network interface. |
List |
getInterfaceAddresses() |
Get a List of all or a subset of the InterfaceAddresses of this network interface. |
int |
getMTU() |
Returns the Maximum Transmission Unit (MTU) of this interface. |
String |
getName() |
Get the name of this network interface. |
static Enumeration |
getNetworkInterfaces() |
Returns an Enumeration of all the interfaces on this machine. |
NetworkInterface |
getParent() |
Returns the parent NetworkInterface of this interface if this is a subinterface, or null if it is a physical (non virtual) interface or has no parent. |
Enumeration |
getSubInterfaces() |
Get an Enumeration with all the subinterfaces (also known as virtual interfaces) attached to this network interface. |
Stream |
inetAddresses() |
Get a Stream of all or a subset of the InetAddresses bound to this network interface. |
boolean |
isLoopback() |
Returns whether a network interface is a loopback interface. |
boolean |
isPointToPoint() |
Returns whether a network interface is a point to point interface. |
boolean |
isUp() |
Returns whether a network interface is up and running. |
boolean |
isVirtual() |
Returns whether this interface is a virtual interface (also called subinterface). |
static Stream |
networkInterfaces() |
Returns a Stream of all the interfaces on this machine. |
Stream |
subInterfaces() |
Get a Stream of all subinterfaces (also known as virtual interfaces) attached to this network interface. |
boolean |
supportsMulticast() |
Returns whether a network interface supports multicasting or not. |
public String getName()
public Enumeration<InetAddress> getInetAddresses()
If there is a security manager, its checkConnect
method is called for each InetAddress. Only InetAddresses where the checkConnect
doesn't throw a SecurityException will be returned in the Enumeration. However, if the caller has the NetPermission
("getNetworkInformation") permission, then all InetAddresses are returned.
public Stream<InetAddress> inetAddresses()
If there is a security manager, its checkConnect
method is called for each InetAddress. Only InetAddresses where the checkConnect
doesn't throw a SecurityException will be returned in the Stream. However, if the caller has the NetPermission
("getNetworkInformation") permission, then all InetAddresses are returned.
public List<InterfaceAddress> getInterfaceAddresses()
InterfaceAddresses
of this network interface. If there is a security manager, its checkConnect
method is called with the InetAddress for each InterfaceAddress. Only InterfaceAddresses where the checkConnect
doesn't throw a SecurityException will be returned in the List.
List
object with all or a subset of the InterfaceAddress of this network interfacepublic Enumeration<NetworkInterface> getSubInterfaces()
For instance eth0:1 will be a subinterface to eth0.
public Stream<NetworkInterface> subInterfaces()
public NetworkInterface getParent()
null
if it is a physical (non virtual) interface or has no parent.NetworkInterface
this interface is attached to.public int getIndex()
-1
for unknown. This is a system specific value and interfaces with the same name can have different indexes on different machines.-1
if the index is unknownpublic String getDisplayName()
public static NetworkInterface getByName(String name) throws SocketException
name
- The name of the network interface.NetworkInterface
with the specified name, or null
if there is no network interface with the specified name.SocketException
- If an I/O error occurs.NullPointerException
- If the specified name is null
.public static NetworkInterface getByIndex(int index) throws SocketException
index
- an integer, the index of the interfacenull
if there is no interface with such an index on the systemSocketException
- if an I/O error occurs.IllegalArgumentException
- if index has a negative valuepublic static NetworkInterface getByInetAddress(InetAddress addr) throws SocketException
If the specified IP address is bound to multiple network interfaces it is not defined which network interface is returned.
addr
- The InetAddress
to search with.NetworkInterface
or null
if there is no network interface with the specified IP address.SocketException
- If an I/O error occurs.NullPointerException
- If the specified address is null
.public static Enumeration<NetworkInterface> getNetworkInterfaces() throws SocketException
Enumeration
of all the interfaces on this machine. The Enumeration
contains at least one element, possibly representing a loopback interface that only supports communication between entities on this machine.getInetAddresses()
to obtain all IP addresses for this nodeSocketException
- if an I/O error occurs, or if the platform does not have at least one configured network interface.public static Stream<NetworkInterface> networkInterfaces() throws SocketException
Stream
of all the interfaces on this machine. The Stream
contains at least one interface, possibly representing a loopback interface that only supports communication between entities on this machine.inetAddresses()
} to obtain a stream of all IP addresses for this node, for example:
Stream<InetAddress> addrs = NetworkInterface.networkInterfaces()
.flatMap(NetworkInterface::inetAddresses);
SocketException
- if an I/O error occurs, or if the platform does not have at least one configured network interface.public boolean isUp() throws SocketException
true
if the interface is up and running.SocketException
- if an I/O error occurs.public boolean isLoopback() throws SocketException
true
if the interface is a loopback interface.SocketException
- if an I/O error occurs.public boolean isPointToPoint() throws SocketException
true
if the interface is a point to point interface.SocketException
- if an I/O error occurs.public boolean supportsMulticast() throws SocketException
true
if the interface supports Multicasting.SocketException
- if an I/O error occurs.public byte[] getHardwareAddress() throws SocketException
NetPermission
("getNetworkInformation").null
if the address doesn't exist, is not accessible or a security manager is set and the caller does not have the permission NetPermission("getNetworkInformation")SocketException
- if an I/O error occurs.public int getMTU() throws SocketException
SocketException
- if an I/O error occurs.public boolean isVirtual()
true
if this interface is a virtual interface.public boolean equals(Object obj)
true
if and only if the argument is not null
and it represents the same NetworkInterface as this object. Two instances of NetworkInterface
represent the same NetworkInterface if both the name and the set of InetAddress
es bound to the interfaces are equal.
equals
in class Object
NetworkInterface
objects referring to the same underlying interface may not compare equal if the addresses of the underlying interface are being dynamically updated by the system.obj
- the object to compare against.true
if the objects are the same; false
otherwise.
© 1993, 2023, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/net/NetworkInterface.html