tigase.util
Class DNSResolver

java.lang.Object
  tigase.util.DNSResolver

public class DNSResolver
extends Object

DNSResolver class for handling DNS names

Since:

Mon Sep 11 09:59:02 2006

Author:

Artur Hefczyc

Field Summary

static Map<String,DNSEntry>	ip_cache Field description
static Map<String,DNSEntry[]>	srv_cache Field description

Constructor Summary

DNSResolver()

Method Summary

static String	getDefaultHostname() Method description
static String[]	getDefHostNames() Method description
static String	getHostIP(String hostname) Resolve IP address for the given hostname
static String[]	getHostIPs(String hostname) Resolve all IP addresses for the given hostname
static DNSEntry[]	getHostSRV_Entries(String hostname) Retrieves list of SRV DNS entries for given hostname.
static DNSEntry[]	getHostSRV_Entries(String hostname, String service, int defPort) Retrieves list of DNS entries for given hostname.
static DNSEntry	getHostSRV_Entry(String hostname) Retrieves service DNS entry with highest priority for given hostname.
static DNSEntry	getHostSRV_Entry(String hostname, String service, int defPort) Retrieves list of DNS entries for given hostname.
static String	getHostSRV_IP(String hostname) Returns IP address of the machine providing the service.
static void	main(String[] args) main method outputting various information about hostnames

Methods inherited from class java.lang.Object

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

Field Detail

srv_cache

public static Map<String,DNSEntry[]> srv_cache

Field description

ip_cache

public static Map<String,DNSEntry> ip_cache

Field description

Constructor Detail

DNSResolver

public DNSResolver()

Method Detail

getDefHostNames

public static String[] getDefHostNames()

Method description

Returns:

getDefaultHostname

public static String getDefaultHostname()

Method description

Returns:

getHostIP

public static String getHostIP(String hostname)
                        throws UnknownHostException

Resolve IP address for the given hostname

Parameters:

hostname - the domain name for which this record is valid

Returns:

IP address of the machine providing the service.

Throws:

UnknownHostException

getHostIPs

public static String[] getHostIPs(String hostname)
                           throws UnknownHostException

Resolve all IP addresses for the given hostname

Parameters:

hostname - the domain name for which this record is valid

Returns:

Array of all IP addresses on which target host provide service.

Throws:

UnknownHostException

getHostSRV_Entries

public static DNSEntry[] getHostSRV_Entries(String hostname)
                                     throws UnknownHostException

Retrieves list of SRV DNS entries for given hostname. Performs lookup for _xmpp-server._tcp SRV records.

Parameters:

hostname - the domain name for which this record is valid

Returns:

Array of the DNSEntry objects containing SRV DNS records

Throws:

UnknownHostException

getHostSRV_Entries

public static DNSEntry[] getHostSRV_Entries(String hostname,
                                            String service,
                                            int defPort)
                                     throws UnknownHostException

Retrieves list of DNS entries for given hostname. Allow specifying particular type of SRV record.

Parameters:

hostname - the domain name for which this record is valid

service - type of SRV records, for example _xmpp-server._tcp

defPort - default port number in case DNS records is missing one.

Returns:

Array of the DNSEntry records

Throws:

UnknownHostException

getHostSRV_Entry

public static DNSEntry getHostSRV_Entry(String hostname)
                                 throws UnknownHostException

Retrieves service DNS entry with highest priority for given hostname. Performs lookup for _xmpp-server._tcp SRV records.

Parameters:

hostname - name to resolve

Returns:

DNSEntry object containing DNS record with highest priority for given hostname

Throws:

UnknownHostException

getHostSRV_Entry

public static DNSEntry getHostSRV_Entry(String hostname,
                                        String service,
                                        int defPort)
                                 throws UnknownHostException

Retrieves list of DNS entries for given hostname. Allow specifying particular type of SRV record.

Parameters:

hostname - name to resolve

service - type of SRV records, for example _xmpp-server._tcp

defPort - default port number in case DNS records is missing one.

Returns:

DNSEntry object containing DNS record with highest priority for given hostname

Throws:

UnknownHostException

getHostSRV_IP

public static String getHostSRV_IP(String hostname)
                            throws UnknownHostException

Returns IP address of the machine providing the service.

Parameters:

hostname - the domain name for which this record is valid

Returns:

Throws:

UnknownHostException

main

public static void main(String[] args)
                 throws Exception

main method outputting various information about hostnames

Parameters:

args - a String[] containing domains to query, if none provided default one will be used

Throws:

Exception