Package org.nuxeo.ecm.directory.ldap.dns

Class DNSServiceResolverImpl

java.lang.Object

org.nuxeo.ecm.directory.ldap.dns.DNSServiceResolverImpl

All Implemented Interfaces:

DNSServiceResolver

public class DNSServiceResolverImpl
extends Object
implements DNSServiceResolver

Utility class to perform DNS lookups for services.

Field Summary

Fields

Modifier and Type	Field	Description
protected Map<String,List<DNSServiceEntry>>	cache	Create a cache to hold the at most 100 recent DNS lookups for a period of 10 minutes.
protected DirContext	context
protected static DNSServiceResolver	instance
protected long	lastCacheUpdate
static Log	log
protected long	maxDelay
protected static String	SRV_RECORD

Fields inherited from interface org.nuxeo.ecm.directory.ldap.dns.DNSServiceResolver

DNS_CACHE_EXPIRY, LDAP_SERVICE_PREFIX

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	DNSServiceResolverImpl()

Method Summary

Modifier and Type	Method	Description
static DNSServiceResolver	getInstance()
protected List<DNSServiceEntry>	resolveDnsServiceRecord(String service, String domain)	Returns the host name and port that a server providing the specified service can be reached at.
List<DNSServiceEntry>	resolveLDAPDomainServers(String domain)	Returns a list of LDAP servers for the specified domain by performing an SRV DNS lookup on _ldap._tcp.${domain}.
List<DNSServiceEntry>	resolveLDAPDomainServers(String domain, String prefix)	Returns a list of LDAP servers for the specified domain by performing an SRV DNS lookup using a custom DNS service prefix.

Methods inherited from class java.lang.Object

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

Field Detail

log

public static final Log log

instance

protected static DNSServiceResolver instance

SRV_RECORD

protected static final String SRV_RECORD

See Also:

Constant Field Values

cache

protected Map<String,List<DNSServiceEntry>> cache

Create a cache to hold the at most 100 recent DNS lookups for a period of 10 minutes.

lastCacheUpdate

protected long lastCacheUpdate

maxDelay

protected final long maxDelay

context

protected final DirContext context

Constructor Detail

DNSServiceResolverImpl

protected DNSServiceResolverImpl()

Method Detail

getInstance

public static DNSServiceResolver getInstance()

resolveDnsServiceRecord

protected List<DNSServiceEntry> resolveDnsServiceRecord(String service,
                                                        String domain)
                                                 throws NamingException

Returns the host name and port that a server providing the specified service can be reached at. A DNS lookup for a SRV record in the form "_service.example.com" is attempted.

As an example, a lookup for "example.com" for the service _gc._tcp may return "dc01.example.com:3268".

Parameters:

service - the service.

domain - the domain.

Returns:

a List of DNSServiceEntrys, which encompasses the hostname and port that the server can be reached at for the specified domain.

Throws:

NamingException - if the DNS server is unreachable

resolveLDAPDomainServers

public List<DNSServiceEntry> resolveLDAPDomainServers(String domain)
                                               throws NamingException

Description copied from interface: DNSServiceResolver

Returns a list of LDAP servers for the specified domain by performing an SRV DNS lookup on _ldap._tcp.${domain}.

Specified by:

resolveLDAPDomainServers in interface DNSServiceResolver

Returns:

the list of SRV dns entries

Throws:

NamingException

resolveLDAPDomainServers

public List<DNSServiceEntry> resolveLDAPDomainServers(String domain,
                                                      String prefix)
                                               throws NamingException

Description copied from interface: DNSServiceResolver

Returns a list of LDAP servers for the specified domain by performing an SRV DNS lookup using a custom DNS service prefix.

Specified by:

resolveLDAPDomainServers in interface DNSServiceResolver

prefix - custom SRV prefix such as "_gc._tcp"

Returns:

the list of SRV dns entries

Throws:

NamingException