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Class InetAddressResolver.LookupPolicy

java.lang.Object

java.net.spi.InetAddressResolver.LookupPolicy

Enclosing interface:: InetAddressResolver

public static final class InetAddressResolver.LookupPolicy extends Object

A LookupPolicy object describes characteristics that can be applied to a lookup operation. In particular, it is used to specify the ordering and which filtering should be performed when looking up host addresses.

The default platform-wide lookup policy is constructed by consulting System Properties which affect how IPv4 and IPv6 addresses are returned.

Since:: 18

Field Summary

Modifier and Type	Field	Description
`static final int`	`IPV4`	Characteristic value signifying if IPv4 addresses need to be queried during lookup.
`static final int`	`IPV4_FIRST`	Characteristic value signifying if IPv4 addresses should be returned first by `InetAddressResolver`.
`static final int`	`IPV6`	Characteristic value signifying if IPv6 addresses need to be queried during lookup.
`static final int`	`IPV6_FIRST`	Characteristic value signifying if IPv6 addresses should be returned first by `InetAddressResolver`.

Method Summary

Modifier and Type	Method	Description
`int`	`characteristics()`	Returns the set of characteristics of this lookup policy.
`static InetAddressResolver.LookupPolicy`	`of(int characteristics)`	This factory method creates a `LookupPolicy` instance with the given `characteristics` value.

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

IPV4

@Native public static final int IPV4

Characteristic value signifying if IPv4 addresses need to be queried during lookup.

See Also:

IPV6

@Native public static final int IPV6

Characteristic value signifying if IPv6 addresses need to be queried during lookup.

See Also:

IPV4_FIRST

@Native public static final int IPV4_FIRST

Characteristic value signifying if IPv4 addresses should be returned first by InetAddressResolver.

See Also:

IPV6_FIRST

@Native public static final int IPV6_FIRST

Characteristic value signifying if IPv6 addresses should be returned first by InetAddressResolver.

See Also:

Method Details

of

public static InetAddressResolver.LookupPolicy of(int characteristics)

This factory method creates a LookupPolicy instance with the given characteristics value.

The characteristics value is an integer bit mask which defines parameters of a forward lookup operation. These parameters define at least:

the family type of the returned addresses
the order in which a resolver implementation should return its results

To request addresses of specific family types the following bit masks can be combined:

IPV4: to request IPv4 addresses
IPV6: to request IPv6 addresses

It is an error if neither IPV4 or IPV6 are set.

To request a specific ordering of the results:

IPV4_FIRST: return IPv4 addresses before any IPv6 address
IPV6_FIRST: return IPv6 addresses before any IPv4 address

If neither IPV4_FIRST or IPV6_FIRST are set it implies "system" order of addresses. It is an error to request both IPV4_FIRST and IPV6_FIRST.

Parameters:

characteristics - a value which represents the set of lookup characteristics

Returns:

an instance of InetAddressResolver.LookupPolicy

Throws:

IllegalArgumentException - if an illegal characteristics bit mask is provided

See Also:

characteristics

public int characteristics()

Returns the set of characteristics of this lookup policy.

Returns:

a characteristics value

See Also:

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/net/spi/InetAddressResolver.LookupPolicy.html