org.xbill.DNS.lookup

Class LookupSession

java.lang.Object

org.xbill.DNS.lookup.LookupSession

public class LookupSession
extends java.lang.Object

LookupSession provides facilities to make DNS Queries. A LookupSession is intended to be long lived, and it's behaviour can be configured using the properties of the LookupSession.LookupSessionBuilder instance returned by builder().

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	LookupSession.LookupSessionBuilder A builder for LookupSession instances.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Map<java.lang.Integer,Cache>	caches
private boolean	cycleResults
static int	DEFAULT_MAX_ITERATIONS
static int	DEFAULT_NDOTS
private java.util.concurrent.Executor	executor
private HostsFileParser	hostsFileParser
private int	maxRedirects
private int	ndots
private Resolver	resolver
private java.util.List<Name>	searchPath

Constructor Summary

Constructors

Modifier	Constructor and Description
private	LookupSession(@NonNull Resolver resolver, int maxRedirects, int ndots, java.util.List<Name> searchPath, boolean cycleResults, java.util.List<Cache> caches, HostsFileParser hostsFileParser, java.util.concurrent.Executor executor)

Method Summary

Modifier and Type	Method and Description
static LookupSession.LookupSessionBuilder	builder() Returns an empty LookupSession.LookupSessionBuilder instance.
private static LookupResult	buildResult(Message answer, java.util.List<Name> aliases, Record query) Returns a LookupResult if this response was a non-exceptional empty result, else null.
private <T extends java.lang.Throwable> java.util.concurrent.CompletionStage<LookupResult>	completeExceptionally(T failure)
static LookupSession.LookupSessionBuilder	defaultBuilder() Returns a LookupSession.LookupSessionBuilder instance initialized with defaults.
(package private) java.util.List<Name>	expandName(Name name) Generate a stream of names according to the search path application semantics.
java.util.concurrent.CompletionStage<LookupResult>	lookupAsync(Name name, int type) Make an asynchronous lookup of the provided name using the default DClass.IN.
java.util.concurrent.CompletionStage<LookupResult>	lookupAsync(Name name, int type, int dclass) Make an asynchronous lookup of the provided name.
private java.util.concurrent.CompletionStage<LookupResult>	lookupUntilSuccess(java.util.Iterator<Name> names, int type, int dclass)
private java.util.concurrent.CompletionStage<LookupResult>	lookupWithCache(Record queryRecord, java.util.List<Name> aliases)
private LookupResult	lookupWithHosts(java.util.List<Name> names, int type)
private java.util.concurrent.CompletionStage<LookupResult>	lookupWithResolver(Record queryRecord, java.util.List<Name> aliases)
private Message	maybeAddToCache(Message message)
private java.util.concurrent.CompletionStage<LookupResult>	maybeFollowRedirect(LookupResult response, Record query, int redirectCount)
private java.util.concurrent.CompletionStage<LookupResult>	maybeFollowRedirectsInAnswer(LookupResult response, Record query, int redirectCount)
private java.util.concurrent.CompletionStage<LookupResult>	resolveRedirects(LookupResult response, Record query)
private static Name	safeConcat(Name name, Name suffix)
private java.util.concurrent.CompletionStage<LookupResult>	setResponseToMessageFuture(SetResponse setResponse, Record queryRecord, java.util.List<Name> aliases)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MAX_ITERATIONS

public static final int DEFAULT_MAX_ITERATIONS

See Also:

Constant Field Values

DEFAULT_NDOTS

public static final int DEFAULT_NDOTS

See Also:

Constant Field Values

resolver

private final Resolver resolver

maxRedirects

private final int maxRedirects

ndots

private final int ndots

searchPath

private final java.util.List<Name> searchPath

cycleResults

private final boolean cycleResults

caches

private final java.util.Map<java.lang.Integer,Cache> caches

hostsFileParser

private final HostsFileParser hostsFileParser

executor

private final java.util.concurrent.Executor executor

Constructor Detail

LookupSession

private LookupSession(@NonNull
                      @NonNull Resolver resolver,
                      int maxRedirects,
                      int ndots,
                      java.util.List<Name> searchPath,
                      boolean cycleResults,
                      java.util.List<Cache> caches,
                      HostsFileParser hostsFileParser,
                      java.util.concurrent.Executor executor)

Method Detail

builder

public static LookupSession.LookupSessionBuilder builder()

Returns an empty LookupSession.LookupSessionBuilder instance. See defaultBuilder() for a builder initialized with defaults.

defaultBuilder

public static LookupSession.LookupSessionBuilder defaultBuilder()

Returns a LookupSession.LookupSessionBuilder instance initialized with defaults.

• Resolver: an ExtendedResolver initialized with the system's default DNS servers as determined by ResolverConfig.
• ndots: as determined by ResolverConfig.
• Cache: A cache for the IN class is installed.
• Hosts: The local host database file is used.

lookupAsync

public java.util.concurrent.CompletionStage<LookupResult> lookupAsync(Name name,
                                                                      int type)

Make an asynchronous lookup of the provided name using the default DClass.IN.

Parameters:

name - the name to look up.

type - the type to look up, values should correspond to constants in Type.

Returns:

A CompletionStage what will yield the eventual lookup result.

lookupAsync

public java.util.concurrent.CompletionStage<LookupResult> lookupAsync(Name name,
                                                                      int type,
                                                                      int dclass)

Make an asynchronous lookup of the provided name.

Parameters:

name - the name to look up.

type - the type to look up, values should correspond to constants in Type.

dclass - the class to look up, values should correspond to constants in DClass.

Returns:

A CompletionStage what will yield the eventual lookup result.

expandName

java.util.List<Name> expandName(Name name)

Generate a stream of names according to the search path application semantics. The semantics of this is a bit odd, but they are inherited from Lookup. Note that the stream returned is never empty, as it will at the very least always contain name.

safeConcat

private static Name safeConcat(Name name,
                               Name suffix)

lookupWithHosts

private LookupResult lookupWithHosts(java.util.List<Name> names,
                                     int type)

lookupUntilSuccess

private java.util.concurrent.CompletionStage<LookupResult> lookupUntilSuccess(java.util.Iterator<Name> names,
                                                                              int type,
                                                                              int dclass)

lookupWithCache

private java.util.concurrent.CompletionStage<LookupResult> lookupWithCache(Record queryRecord,
                                                                           java.util.List<Name> aliases)

lookupWithResolver

private java.util.concurrent.CompletionStage<LookupResult> lookupWithResolver(Record queryRecord,
                                                                              java.util.List<Name> aliases)

maybeAddToCache

private Message maybeAddToCache(Message message)

setResponseToMessageFuture

private java.util.concurrent.CompletionStage<LookupResult> setResponseToMessageFuture(SetResponse setResponse,
                                                                                      Record queryRecord,
                                                                                      java.util.List<Name> aliases)

completeExceptionally

private <T extends java.lang.Throwable> java.util.concurrent.CompletionStage<LookupResult> completeExceptionally(T failure)

resolveRedirects

private java.util.concurrent.CompletionStage<LookupResult> resolveRedirects(LookupResult response,
                                                                            Record query)

maybeFollowRedirect

private java.util.concurrent.CompletionStage<LookupResult> maybeFollowRedirect(LookupResult response,
                                                                               Record query,
                                                                               int redirectCount)

maybeFollowRedirectsInAnswer

private java.util.concurrent.CompletionStage<LookupResult> maybeFollowRedirectsInAnswer(LookupResult response,
                                                                                        Record query,
                                                                                        int redirectCount)

buildResult

private static LookupResult buildResult(Message answer,
                                        java.util.List<Name> aliases,
                                        Record query)

Returns a LookupResult if this response was a non-exceptional empty result, else null.