com.unboundid.ldap.sdk.SRVRecordSet Maven / Gradle / Ivy
/*
* Copyright 2011-2017 UnboundID Corp.
* All Rights Reserved.
*/
/*
* Copyright (C) 2011-2017 UnboundID Corp.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (GPLv2 only)
* or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see .
*/
package com.unboundid.ldap.sdk;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import java.util.logging.Level;
import javax.naming.NamingEnumeration;
import javax.naming.directory.Attribute;
import javax.naming.directory.Attributes;
import javax.naming.directory.DirContext;
import javax.naming.directory.InitialDirContext;
import com.unboundid.util.Debug;
import com.unboundid.util.DebugType;
import com.unboundid.util.StaticUtils;
import com.unboundid.util.NotMutable;
import com.unboundid.util.ThreadSafety;
import com.unboundid.util.ThreadSafetyLevel;
import static com.unboundid.ldap.sdk.LDAPMessages.*;
/**
* This class provides a data structure for holding information about a set of
* DNS SRV records, and a method for ordering them for ordering them based on
* their priorities and weights.
*/
@NotMutable()
@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
final class SRVRecordSet
implements Serializable
{
/**
* The name of the JNDI context factory that should be used for querying DNS.
*/
private static final String JNDI_DNS_CONTEXT_FACTORY =
"com.sun.jndi.dns.DnsContextFactory";
/**
* The attribute name that will be used to retrieve the SRV record.
*/
private static final String DNS_ATTR_SRV = "SRV";
/**
* The names of the DNS attributes that should be retrieved.
*/
private static final String[] ATTRIBUTE_IDS = { DNS_ATTR_SRV };
/**
* The serial version UID for this serializable class.
*/
private static final long serialVersionUID = 7075112952759306499L;
// The total number of records to be processed.
private final int totalRecords;
// A list of all records associated with this set. There is no defined order
// to the list of records.
private final List allRecords;
// A list of record sets ordered by ascending priority.
private final List recordSets;
// The expiration time for this set.
private final long expirationTime;
/**
* Creates a new SRV record set with the provided information.
*
* @param expirationTime The time that this information should be considered
* expired.
* @param records The set of all records to be processed. It must
* not be {@code null} or empty.
*/
SRVRecordSet(final long expirationTime, final List records)
{
this.expirationTime = expirationTime;
allRecords = Collections.unmodifiableList(records);
totalRecords = records.size();
final TreeMap> m =
new TreeMap>();
for (final SRVRecord r : records)
{
final Long priority = Long.valueOf(r.getPriority());
List l = m.get(priority);
if (l == null)
{
l = new ArrayList(records.size());
m.put(priority, l);
}
l.add(r);
}
final ArrayList l =
new ArrayList(m.size());
for (final Map.Entry> e : m.entrySet())
{
l.add(new SRVRecordPrioritySet(e.getKey(), e.getValue()));
}
recordSets = Collections.unmodifiableList(l);
}
/**
* Retrieves the expiration time for this set.
*
* @return The expiration time for this set.
*/
long getExpirationTime()
{
return expirationTime;
}
/**
* Indicates whether the information in this record set is expired.
*
* @return {@code true} if the expiration time has passed, or {@code false}
* if not.
*/
boolean isExpired()
{
return (System.currentTimeMillis() >= expirationTime);
}
/**
* Retrieves a list of all SRV records ordered by priority and weight.
*
* @return A list of all SRV records ordered by priority and weight.
*/
List getOrderedRecords()
{
final ArrayList l = new ArrayList(totalRecords);
for (final SRVRecordPrioritySet s : recordSets)
{
l.addAll(s.getOrderedRecords());
}
return l;
}
/**
* Attempts to communicate with DNS in order to retrieve a record set.
*
* @param name The name of the SRV record to retrieve.
* @param jndiProperties The properties to use to initialize the JNDI
* context.
* @param ttlMillis Specifies the maximum length of time in
* milliseconds that DNS information should be cached
* before it needs to be retrieved again.
*
* @return The record set retrieved from DNS.
*
* @throws LDAPException If an error occurs while querying DNS or while
* parsing the results.
*/
static SRVRecordSet getRecordSet(final String name,
final Hashtable jndiProperties,
final long ttlMillis)
throws LDAPException
{
final ArrayList recordStrings = new ArrayList(10);
DirContext context = null;
try
{
if (Debug.debugEnabled(DebugType.CONNECT))
{
Debug.debug(Level.INFO, DebugType.CONNECT,
"Issuing JNDI query to retrieve DNS SRV record '" + name +
"' using properties '" + jndiProperties + "'.");
}
context = new InitialDirContext(jndiProperties);
final Attributes recordAttributes =
context.getAttributes(name, ATTRIBUTE_IDS);
context.close();
final Attribute srvAttr = recordAttributes.get(DNS_ATTR_SRV);
if (srvAttr == null)
{
throw new LDAPException(ResultCode.LOCAL_ERROR,
ERR_SRV_RECORD_SET_NO_RECORDS.get(name));
}
final NamingEnumeration values = srvAttr.getAll();
while (values.hasMore())
{
final Object value = values.next();
recordStrings.add(String.valueOf(value));
}
values.close();
}
catch (final LDAPException le)
{
Debug.debugException(le);
throw le;
}
catch (final Exception e)
{
Debug.debugException(e);
throw new LDAPException(ResultCode.LOCAL_ERROR,
ERR_SRV_RECORD_SET_ERROR_QUERYING_DNS.get(name,
StaticUtils.getExceptionMessage(e)),
e);
}
finally
{
if (context != null)
{
try
{
context.close();
}
catch (final Exception e)
{
Debug.debugException(e);
}
}
}
if (recordStrings.isEmpty())
{
throw new LDAPException(ResultCode.LOCAL_ERROR,
ERR_SRV_RECORD_SET_NO_RECORDS.get(name));
}
final List recordList =
new ArrayList(recordStrings.size());
for (final String s : recordStrings)
{
final SRVRecord r = new SRVRecord(s);
recordList.add(r);
if (Debug.debugEnabled(DebugType.CONNECT))
{
Debug.debug(Level.INFO, DebugType.CONNECT,
"Decoded DNS SRV record " + r.toString());
}
}
return new SRVRecordSet(System.currentTimeMillis() + ttlMillis, recordList);
}
/**
* Retrieves a string representation of this priority server set.
*
* @return A string representation of this priority server set.
*/
@Override()
public String toString()
{
final StringBuilder buffer = new StringBuilder();
toString(buffer);
return buffer.toString();
}
/**
* Appends a string representation of this priority buffer set to the provided
* buffer.
*
* @param buffer The buffer to which the information should be appended.
*/
void toString(final StringBuilder buffer)
{
buffer.append("SRVRecordSet(records={");
final Iterator iterator = allRecords.iterator();
while (iterator.hasNext())
{
buffer.append(iterator.next().toString());
if (iterator.hasNext())
{
buffer.append(", ");
}
}
buffer.append("})");
}
}