IpAddress sealed

sealed class IpAddress extends Host

The sealed base type for IP addresses.

Subtypes are Ipv4Address (32-bit) and Ipv6Address (128-bit). Internally stored as a Uint8List of 4 or 16 bytes respectively.

Inheritance

Object → Ordered<A> → Host → IpAddress

Implementers

• Ipv4Address
• Ipv6Address

Properties

asHost no setter inherited

Host get asHost

Returns this as a Host (identity).

Inherited from Host.

Implementation

Host get asHost => this;

asIpAddress no setter

IpAddress get asIpAddress

Returns this as an IpAddress (identity).

Implementation

IpAddress get asIpAddress => this;

bitSize no setter

int get bitSize

The number of bits in this address (32 for IPv4, 128 for IPv6).

Implementation

int get bitSize => fold((_) => 32, (_) => 128);

hashCode no setter override

int get hashCode

The hash code for this object.

A hash code is a single integer which represents the state of the object that affects operator == comparisons.

All objects have hash codes. The default hash code implemented by Object represents only the identity of the object, the same way as the default operator == implementation only considers objects equal if they are identical (see identityHashCode).

If operator == is overridden to use the object state instead, the hash code must also be changed to represent that state, otherwise the object cannot be used in hash based data structures like the default Set and Map implementations.

Hash codes must be the same for objects that are equal to each other according to operator ==. The hash code of an object should only change if the object changes in a way that affects equality. There are no further requirements for the hash codes. They need not be consistent between executions of the same program and there are no distribution guarantees.

Objects that are not equal are allowed to have the same hash code. It is even technically allowed that all instances have the same hash code, but if clashes happen too often, it may reduce the efficiency of hash-based data structures like HashSet or HashMap.

If a subclass overrides hashCode, it should override the operator == operator as well to maintain consistency.

Implementation

@override
int get hashCode => Object.hashAll(_bytes);

isMappedV4 no setter

bool get isMappedV4

Returns true if this is an IPv6 address in the ::ffff:0:0/96 (IPv4-mapped) block.

Implementation

bool get isMappedV4 => fold((_) => false, Ipv6Address.MappedV4Block.contains);

isMulticast no setter

bool get isMulticast

Returns true if this address is in the multicast range.

Implementation

bool get isMulticast;

isSourceSpecificMulticast no setter

bool get isSourceSpecificMulticast

Returns true if this address is in the source-specific multicast (SSM) range.

Implementation

bool get isSourceSpecificMulticast;

runtimeType no setter inherited

Type get runtimeType

A representation of the runtime type of the object.

Inherited from Object.

Implementation

external Type get runtimeType;

version no setter

IpVersion get version

The IP version of this address.

Implementation

IpVersion get version => fold((_) => IpVersion.v4, (_) => IpVersion.v6);

Methods

asIpv4()

Option<Ipv4Address> asIpv4()

Returns Some(v4) if this address is (or collapses to) an Ipv4Address, otherwise None.

Implementation

Option<Ipv4Address> asIpv4() => collapseMappedV4().fold((v4) => Some(v4), (_) => none());

asIpv6()

Option<Ipv6Address> asIpv6()

Returns Some(v6) if this is an Ipv6Address, otherwise None.

Implementation

Option<Ipv6Address> asIpv6() => fold((_) => none(), (v6) => Some(v6));

asMulticast()

Option<Multicast<IpAddress>> asMulticast()

Returns a Multicast wrapper if this address is a multicast address, otherwise None.

Implementation

Option<Multicast<IpAddress>> asMulticast() => Multicast.fromIpAddress(this);

asSourceSpecificMulticast()

Option<SourceSpecificMulticastStrict<IpAddress>> asSourceSpecificMulticast()

Returns a strict SourceSpecificMulticastStrict wrapper if this address is in the SSM range, otherwise None.

Implementation

Option<SourceSpecificMulticastStrict<IpAddress>> asSourceSpecificMulticast() =>
    SourceSpecificMulticast.fromIpAddress(this);

asSourceSpecificMulticastLenient()

Option<SourceSpecificMulticast<IpAddress>> asSourceSpecificMulticastLenient()

Returns a lenient SourceSpecificMulticast wrapper if this address is any multicast address, otherwise None.

Implementation

Option<SourceSpecificMulticast<IpAddress>> asSourceSpecificMulticastLenient() =>
    SourceSpecificMulticast.fromIpAddressLenient(this);

collapseMappedV4()

IpAddress collapseMappedV4()

If this is an IPv6 address that is a mapped IPv4 address (i.e. ::ffff:a.b.c.d), returns the corresponding Ipv4Address. Otherwise returns this address unchanged.

Implementation

IpAddress collapseMappedV4() => fold(identity, (v6) {
  if (v6.isMappedV4) {
    return IpAddress.fromBytes(
      v6.toBytes().toIList().takeRight(4).toList(),
    ).getOrElse(() => throw Exception('IpAddress.collapseMappedV4 failure: $v6'));
  } else {
    return v6;
  }
});

compareTo() inherited

int compareTo(Host that)

Compares this object to another object.

Returns a value like a Comparator when comparing this to other. That is, it returns a negative integer if this is ordered before other, a positive integer if this is ordered after other, and zero if this and other are ordered together.

The other argument must be a value that is comparable to this object.

Inherited from Host.

Implementation

@override
int compareTo(Host that) {
  return switch (this) {
    final Ipv4Address x => switch (that) {
      final Ipv4Address y => IpAddress.compareBytes(x, y),
      final Ipv6Address y => IpAddress.compareBytes(x.toCompatV6(), y),
      _ => -1,
    },
    final Ipv6Address x => switch (that) {
      final Ipv4Address y => IpAddress.compareBytes(x, y.toCompatV6()),
      final Ipv6Address y => IpAddress.compareBytes(x, y),
      _ => -1,
    },
    final Hostname x => switch (that) {
      final Ipv4Address _ => 1,
      final Ipv6Address _ => 1,
      final Hostname y => x.toString().compareTo(y.toString()),
      final IDN y => x.toString().compareTo(y.hostname.toString()),
    },
    final IDN x => switch (that) {
      final Ipv4Address _ => 1,
      final Ipv6Address _ => 1,
      final Hostname y => x.hostname.toString().compareTo(y.toString()),
      final IDN y => x.hostname.toString().compareTo(y.hostname.toString()),
    },
  };
}

fold()

A fold<A>(A Function(Ipv4Address) v4, A Function(Ipv6Address) v6)

Dispatches to v4 or v6 depending on the address family.

Implementation

A fold<A>(Function1<Ipv4Address, A> v4, Function1<Ipv6Address, A> v6);

noSuchMethod() inherited

dynamic noSuchMethod(Invocation invocation)

Invoked when a nonexistent method or property is accessed.

A dynamic member invocation can attempt to call a member which doesn't exist on the receiving object. Example:

dynamic object = 1;
object.add(42); // Statically allowed, run-time error

This invalid code will invoke the noSuchMethod method of the integer 1 with an Invocation representing the .add(42) call and arguments (which then throws).

Classes can override noSuchMethod to provide custom behavior for such invalid dynamic invocations.

A class with a non-default noSuchMethod invocation can also omit implementations for members of its interface. Example:

class MockList<T> implements List<T> {
  noSuchMethod(Invocation invocation) {
    log(invocation);
    super.noSuchMethod(invocation); // Will throw.
  }
}
void main() {
  MockList().add(42);
}

This code has no compile-time warnings or errors even though the MockList class has no concrete implementation of any of the List interface methods. Calls to List methods are forwarded to noSuchMethod, so this code will log an invocation similar to Invocation.method(#add, [42]) and then throw.

If a value is returned from noSuchMethod, it becomes the result of the original invocation. If the value is not of a type that can be returned by the original invocation, a type error occurs at the invocation.

The default behavior is to throw a NoSuchMethodError.

Inherited from Object.

Implementation

@pragma("vm:entry-point")
@pragma("wasm:entry-point")
external dynamic noSuchMethod(Invocation invocation);

prefixBits()

int prefixBits()

Counts the number of leading one-bits in the address, treating the bytes as a network mask. Used to derive the prefix length from a mask address.

Implementation

int prefixBits() {
  int zerosIn(int value, int bits) {
    int res = 0;
    int x = value;

    while ((x & (1 << (bits - 1))) == 0 && res < bits) {
      x = x << 1;
      res++;
    }

    return res;
  }

  int zeros(Uint8List l) {
    int n = 0;

    for (final i in l) {
      n += zerosIn(~i, 8);

      if (n == 0 || n % 8 != 0) {
        return n;
      }
    }

    return n;
  }

  return zeros(_bytes);
}

resolve() inherited

IO<IList<IpAddress>> resolve()

Resolves this host to a list of IpAddress values.

If this is already an IpAddress, returns it immediately. For Hostname and IDN values, performs a DNS lookup via Dns.resolve.

Inherited from Host.

Implementation

IO<IList<IpAddress>> resolve() => switch (this) {
  final IpAddress ip => IO.pure(ilist([ip])),
  final Hostname hostname => Dns.resolve(hostname),
  final IDN idn => Dns.resolve(idn.hostname),
};

reverse()

IO<Hostname> reverse()

Performs a reverse DNS lookup, returning the Hostname associated with this address. Fails the IO if no PTR record is found.

Implementation

IO<Hostname> reverse() => Dns.reverse(this);

reverseOption()

IO<Option<Hostname>> reverseOption()

Performs a reverse DNS lookup, returning Some hostname if a PTR record exists or None otherwise.

Implementation

IO<Option<Hostname>> reverseOption() => Dns.reverseOption(this);

toBytes()

Uint8List toBytes()

Returns a copy of the underlying bytes as a new Uint8List.

Implementation

Uint8List toBytes() => Uint8List.fromList(_bytes.toList());

toString() inherited

String toString()

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Inherited from Object.

Implementation

external String toString();

Operators

operator /()

Cidr<IpAddress> operator /(int prefixBits)

Creates a Cidr block from this address and prefixBits.

Implementation

Cidr<IpAddress> operator &#47;(int prefixBits) => Cidr.of(this, prefixBits);

operator <() inherited

bool operator <(Host that)

Returns true if this value is less than that.

Inherited from Ordered.

Implementation

bool operator <(A that) => compareTo(that) < 0;

operator <=() inherited

bool operator <=(Host that)

Returns true if this value is less than or equal to that.

Inherited from Ordered.

Implementation

bool operator <=(A that) => compareTo(that) <= 0;

operator ==() override

bool operator ==(Object other)

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

• Total: It must return a boolean for all arguments. It should never throw.

• Reflexive: For all objects o, o == o must be true.

• Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.

• Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.

Implementation

@override
bool operator ==(Object other) => switch (other) {
  final IpAddress that =>
    version == that.version && ilist(_bytes).zip(ilist(that._bytes)).forall((t) => t.$1 == t.$2),
  _ => false,
};

operator >() inherited

bool operator >(Host that)

Returns true if this value is greater than that.

Inherited from Ordered.

Implementation

bool operator >(A that) => compareTo(that) > 0;

operator >=() inherited

bool operator >=(Host that)

Returns true if this value is greater than or equal to that.

Inherited from Ordered.

Implementation

bool operator >=(A that) => compareTo(that) >= 0;

Static Methods

compareBytes()

int compareBytes(IpAddress x, IpAddress y)

Compares two IpAddress values byte-by-byte, returning a negative, zero, or positive value.

Implementation

static int compareBytes(IpAddress x, IpAddress y) {
  int i = 0;
  int result = 0;

  final sz = x._bytes.length;

  while (i < sz && result == 0) {
    result = (x._bytes[i] & 0xff).compareTo(y._bytes[i] & 0xff);
    i++;
  }

  return result;
}

fromBytes()

Option<IpAddress> fromBytes(Iterable<int> bytes)

Returns an IpAddress from an iterable of exactly 4 (IPv4) or 16 (IPv6) bytes, or None otherwise.

Implementation

static Option<IpAddress> fromBytes(Iterable<int> bytes) => Ipv4Address.fromByteList(
  bytes,
).map((a) => a.asIpAddress).orElse(() => Ipv6Address.fromByteList(bytes));

fromString() override

Option<IpAddress> fromString(String value)

Parses value as either an IPv4 or IPv6 address string, returning None if parsing fails.

Implementation

static Option<IpAddress> fromString(String value) => Ipv4Address.fromString(
  value,
).map((a) => a.asIpAddress).orElse(() => Ipv6Address.fromString(value));

loopback()

IO<IList<IpAddress>> loopback()

Returns the loopback addresses for the current host via DNS.

Implementation

static IO<IList<IpAddress>> loopback() => Dns.loopback();