Class Inet4Address

java.lang.Object
java.net.InetAddress
java.net.Inet4Address
All Implemented Interfaces:
Serializable

public final class Inet4Address extends InetAddress
This class represents an Internet Protocol version 4 (IPv4) address. Defined by RFC 790: Assigned Numbers, RFC 1918: Address Allocation for Private Internets, and RFC 2365: Administratively Scoped IP Multicast

Textual representation of IPv4 addresses

Textual representation of IPv4 address used as input to methods takes one of the following forms:
  • d.d.d.d
  • d.d.d
  • d.d
  • d

When four parts are specified, each is interpreted as a byte of data and assigned, from left to right, to the four bytes of an IPv4 address.

When a three part address is specified, the last part is interpreted as a 16-bit quantity and placed in the right most two bytes of the network address. This makes the three part address format convenient for specifying Class B network addresses as 128.net.host.

When a two part address is supplied, the last part is interpreted as a 24-bit quantity and placed in the right most three bytes of the network address. This makes the two part address format convenient for specifying Class A network addresses as net.host.

When only one part is given, the value is stored directly in the network address without any byte rearrangement.

These forms support parts specified in decimal format only. For example, the following forms are supported by methods capable of parsing textual representations of IPv4 addresses:

 // Dotted-decimal 'd.d.d.d' form with four part address literal
 InetAddress.getByName("007.008.009.010"); // ==> /7.8.9.10
 InetAddress.getByName("127.0.1.1");       // ==> /127.0.1.1

 // Dotted-decimal 'd.d.d' form with three part address literal,
 // the last part is placed in the right most two bytes
 // of the constructed address
 InetAddress.getByName("127.0.257"); // ==> /127.0.1.1

 // Dotted-decimal 'd.d' form with two part address literal,
 // the last part is placed in the right most three bytes
 // of the constructed address
 Inet4Address.ofLiteral("127.257"); // ==> /127.0.1.1

 // 'd' form with one decimal value that is stored directly in
 // the constructed address bytes without any rearrangement
 Inet4Address.ofLiteral("02130706689"); // ==> /127.0.1.1

For methods that return a textual representation as output value, the first form, i.e. a dotted-quad string, is used.

The Scope of a Multicast Address

Historically the IPv4 TTL field in the IP header has doubled as a multicast scope field: a TTL of 0 means node-local, 1 means link-local, up through 32 means site-local, up through 64 means region-local, up through 128 means continent-local, and up through 255 are global. However, the administrative scoping is preferred. Please refer to RFC 2365: Administratively Scoped IP Multicast
Since:
1.4
External Specifications
See Also:
  • Method Details

    • ofLiteral

      public static Inet4Address ofLiteral(String ipv4AddressLiteral)
      Creates an Inet4Address based on the provided textual representation of an IPv4 address.

      If the provided IPv4 address literal cannot represent a valid IPv4 address an IllegalArgumentException is thrown.

      This method doesn't block, i.e. no reverse lookup is performed.

      Parameters:
      ipv4AddressLiteral - the textual representation of an IPv4 address.
      Returns:
      an Inet4Address object with no hostname set, and constructed from the provided IPv4 address literal.
      Throws:
      IllegalArgumentException - if the ipv4AddressLiteral cannot be parsed as an IPv4 address literal.
      NullPointerException - if the ipv4AddressLiteral is null.
      Since:
      22
    • isMulticastAddress

      public boolean isMulticastAddress()
      Utility routine to check if the InetAddress is an IP multicast address. IP multicast address is a Class D address i.e first four bits of the address are 1110.
      Overrides:
      isMulticastAddress in class InetAddress
      Returns:
      a boolean indicating if the InetAddress is an IP multicast address
    • isAnyLocalAddress

      public boolean isAnyLocalAddress()
      Utility routine to check if the InetAddress is a wildcard address.
      Overrides:
      isAnyLocalAddress in class InetAddress
      Returns:
      a boolean indicating if the InetAddress is a wildcard address.
    • isLoopbackAddress

      public boolean isLoopbackAddress()
      Utility routine to check if the InetAddress is a loopback address.
      Overrides:
      isLoopbackAddress in class InetAddress
      Returns:
      a boolean indicating if the InetAddress is a loopback address; or false otherwise.
    • isLinkLocalAddress

      public boolean isLinkLocalAddress()
      Utility routine to check if the InetAddress is a link local address.
      Overrides:
      isLinkLocalAddress in class InetAddress
      Returns:
      a boolean indicating if the InetAddress is a link local address; or false if address is not a link local unicast address.
    • isSiteLocalAddress

      public boolean isSiteLocalAddress()
      Utility routine to check if the InetAddress is a site local address.
      Overrides:
      isSiteLocalAddress in class InetAddress
      Returns:
      a boolean indicating if the InetAddress is a site local address; or false if address is not a site local unicast address.
    • isMCGlobal

      public boolean isMCGlobal()
      Utility routine to check if the multicast address has global scope.
      Overrides:
      isMCGlobal in class InetAddress
      Returns:
      a boolean indicating if the address has is a multicast address of global scope, false if it is not of global scope or it is not a multicast address
    • isMCNodeLocal

      public boolean isMCNodeLocal()
      Utility routine to check if the multicast address has node scope.
      Overrides:
      isMCNodeLocal in class InetAddress
      Returns:
      a boolean indicating if the address has is a multicast address of node-local scope, false if it is not of node-local scope or it is not a multicast address
    • isMCLinkLocal

      public boolean isMCLinkLocal()
      Utility routine to check if the multicast address has link scope.
      Overrides:
      isMCLinkLocal in class InetAddress
      Returns:
      a boolean indicating if the address has is a multicast address of link-local scope, false if it is not of link-local scope or it is not a multicast address
    • isMCSiteLocal

      public boolean isMCSiteLocal()
      Utility routine to check if the multicast address has site scope.
      Overrides:
      isMCSiteLocal in class InetAddress
      Returns:
      a boolean indicating if the address has is a multicast address of site-local scope, false if it is not of site-local scope or it is not a multicast address
    • isMCOrgLocal

      public boolean isMCOrgLocal()
      Utility routine to check if the multicast address has organization scope.
      Overrides:
      isMCOrgLocal in class InetAddress
      Returns:
      a boolean indicating if the address has is a multicast address of organization-local scope, false if it is not of organization-local scope or it is not a multicast address
    • getAddress

      public byte[] getAddress()
      Returns the raw IP address of this InetAddress object. The result is in network byte order: the highest order byte of the address is in getAddress()[0].
      Overrides:
      getAddress in class InetAddress
      Returns:
      the raw IP address of this object.
    • getHostAddress

      public String getHostAddress()
      Returns the IP address string in textual presentation form.
      Overrides:
      getHostAddress in class InetAddress
      Returns:
      the raw IP address in a string format.
    • hashCode

      public int hashCode()
      Returns a hashcode for this IP address.
      Overrides:
      hashCode in class InetAddress
      Returns:
      a hash code value for this IP address.
      See Also:
    • equals

      public boolean equals(Object obj)
      Compares this object against the specified object. The result is true if and only if the argument is not null and it represents the same IP address as this object.

      Two instances of InetAddress represent the same IP address if the length of the byte arrays returned by getAddress is the same for both, and each of the array components is the same for the byte arrays.

      Overrides:
      equals in class InetAddress
      Parameters:
      obj - the object to compare against.
      Returns:
      true if the objects are the same; false otherwise.
      See Also: