/* * Copyright (c) 2000, 2002, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */package com.sun.jndi.dns;import java.lang.ref.SoftReference;import java.util.Date;import java.util.Vector;/** * ZoneNode extends NameNode to represent a tree of the zones in the * DNS namespace, along with any intermediate nodes between zones. * A ZoneNode that represents a zone may be "populated" with a * NameNode tree containing the zone's contents. * * <p> A populated zone's contents will be flagged as having expired after * the time specified by the minimum TTL value in the zone's SOA record. * * <p> Since zone cuts aren't directly modeled by a tree of ZoneNodes, * ZoneNode.isZoneCut() always returns false. * * <p> The synchronization strategy is documented in DnsContext.java. * * <p> The zone's contents are accessed via a soft reference, so its * heap space may be reclaimed when necessary. The zone may be * repopulated later. * * @author Scott Seligman */class ZoneNode extends NameNode { private SoftReference contentsRef = null; // the zone's namespace private long serialNumber = -1; // the zone data's serial number private Date expiration = null; // time when the zone's data expires ZoneNode(String label) { super(label); } protected NameNode newNameNode(String label) { return new ZoneNode(label); } /* * Clears the contents of this node. If the node was flagged as * expired, it remains so. */ synchronized void depopulate() { contentsRef = null; serialNumber = -1; } /* * Is this node currently populated? */ synchronized boolean isPopulated() { return (getContents() != null); } /* * Returns the zone's contents, or null if the zone is not populated. */ synchronized NameNode getContents() { return (contentsRef != null) ? (NameNode) contentsRef.get() : null; } /* * Has this zone's data expired? */ synchronized boolean isExpired() { return ((expiration != null) && expiration.before(new Date())); } /* * Returns the deepest populated zone on the path specified by a * fully-qualified domain name, or null if there is no populated * zone on that path. Note that a node may be depopulated after * being returned. */ ZoneNode getDeepestPopulated(DnsName fqdn) { ZoneNode znode = this; ZoneNode popNode = isPopulated() ? this : null; for (int i = 1; i < fqdn.size(); i++) { // "i=1" to skip root label znode = (ZoneNode) znode.get(fqdn.getKey(i)); if (znode == null) { break; } else if (znode.isPopulated()) { popNode = znode; } } return popNode; } /* * Populates (or repopulates) a zone given its own fully-qualified * name and its resource records. Returns the zone's new contents. */ NameNode populate(DnsName zone, ResourceRecords rrs) { // assert zone.get(0).equals(""); // zone has root label // assert (zone.size() == (depth() + 1)); // +1 due to root label NameNode newContents = new NameNode(null); for (int i = 0; i < rrs.answer.size(); i++) { ResourceRecord rr = (ResourceRecord) rrs.answer.elementAt(i); DnsName n = rr.getName(); // Ignore resource records whose names aren't within the zone's // domain. Also skip records of the zone's top node, since // the zone's root NameNode is already in place. if ((n.size() > zone.size()) && n.startsWith(zone)) { NameNode nnode = newContents.add(n, zone.size()); if (rr.getType() == ResourceRecord.TYPE_NS) { nnode.setZoneCut(true); } } } // The zone's SOA record is the first record in the answer section. ResourceRecord soa = (ResourceRecord) rrs.answer.firstElement(); synchronized (this) { contentsRef = new SoftReference(newContents); serialNumber = getSerialNumber(soa); setExpiration(getMinimumTtl(soa)); return newContents; } } /* * Set this zone's data to expire in <tt>secsToExpiration</tt> seconds. */ private void setExpiration(long secsToExpiration) { expiration = new Date(System.currentTimeMillis() + 1000 * secsToExpiration); } /* * Returns an SOA record's minimum TTL field. */ private static long getMinimumTtl(ResourceRecord soa) { String rdata = (String) soa.getRdata(); int pos = rdata.lastIndexOf(' ') + 1; return Long.parseLong(rdata.substring(pos)); } /* * Compares this zone's serial number with that of an SOA record. * Zone must be populated. * Returns a negative, zero, or positive integer as this zone's * serial number is less than, equal to, or greater than the SOA * record's. * See ResourceRecord.compareSerialNumbers() for a description of * serial number arithmetic. */ int compareSerialNumberTo(ResourceRecord soa) { // assert isPopulated(); return ResourceRecord.compareSerialNumbers(serialNumber, getSerialNumber(soa)); } /* * Returns an SOA record's serial number. */ private static long getSerialNumber(ResourceRecord soa) { String rdata = (String) soa.getRdata(); // An SOA record ends with: serial refresh retry expire minimum. // Set "beg" to the space before serial, and "end" to the space after. // We go "backward" to avoid dealing with escaped spaces in names. int beg = rdata.length(); int end = -1; for (int i = 0; i < 5; i++) { end = beg; beg = rdata.lastIndexOf(' ', end - 1); } return Long.parseLong(rdata.substring(beg + 1, end)); }}
/*
* Copyright (c) 2000, 2002, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.sun.jndi.dns;
import java.lang.ref.SoftReference;
import java.util.Date;
import java.util.Vector;
/**
* ZoneNode extends NameNode to represent a tree of the zones in the
* DNS namespace, along with any intermediate nodes between zones.
* A ZoneNode that represents a zone may be "populated" with a
* NameNode tree containing the zone's contents.
*
* <p> A populated zone's contents will be flagged as having expired after
* the time specified by the minimum TTL value in the zone's SOA record.
*
* <p> Since zone cuts aren't directly modeled by a tree of ZoneNodes,
* ZoneNode.isZoneCut() always returns false.
*
* <p> The synchronization strategy is documented in DnsContext.java.
*
* <p> The zone's contents are accessed via a soft reference, so its
* heap space may be reclaimed when necessary. The zone may be
* repopulated later.
*
* @author Scott Seligman
*/
class ZoneNode extends NameNode {
private SoftReference contentsRef = null; // the zone's namespace
private long serialNumber = -1; // the zone data's serial number
private Date expiration = null; // time when the zone's data expires
ZoneNode(String label) {
super(label);
}
protected NameNode newNameNode(String label) {
return new ZoneNode(label);
}
/*
* Clears the contents of this node. If the node was flagged as
* expired, it remains so.
*/
synchronized void depopulate() {
contentsRef = null;
serialNumber = -1;
}
/*
* Is this node currently populated?
*/
synchronized boolean isPopulated() {
return (getContents() != null);
}
/*
* Returns the zone's contents, or null if the zone is not populated.
*/
synchronized NameNode getContents() {
return (contentsRef != null)
? (NameNode) contentsRef.get()
: null;
}
/*
* Has this zone's data expired?
*/
synchronized boolean isExpired() {
return ((expiration != null) && expiration.before(new Date()));
}
/*
* Returns the deepest populated zone on the path specified by a
* fully-qualified domain name, or null if there is no populated
* zone on that path. Note that a node may be depopulated after
* being returned.
*/
ZoneNode getDeepestPopulated(DnsName fqdn) {
ZoneNode znode = this;
ZoneNode popNode = isPopulated() ? this : null;
for (int i = 1; i < fqdn.size(); i++) { // "i=1" to skip root label
znode = (ZoneNode) znode.get(fqdn.getKey(i));
if (znode == null) {
break;
} else if (znode.isPopulated()) {
popNode = znode;
}
}
return popNode;
}
/*
* Populates (or repopulates) a zone given its own fully-qualified
* name and its resource records. Returns the zone's new contents.
*/
NameNode populate(DnsName zone, ResourceRecords rrs) {
// assert zone.get(0).equals(""); // zone has root label
// assert (zone.size() == (depth() + 1)); // +1 due to root label
NameNode newContents = new NameNode(null);
for (int i = 0; i < rrs.answer.size(); i++) {
ResourceRecord rr = (ResourceRecord) rrs.answer.elementAt(i);
DnsName n = rr.getName();
// Ignore resource records whose names aren't within the zone's
// domain. Also skip records of the zone's top node, since
// the zone's root NameNode is already in place.
if ((n.size() > zone.size()) && n.startsWith(zone)) {
NameNode nnode = newContents.add(n, zone.size());
if (rr.getType() == ResourceRecord.TYPE_NS) {
nnode.setZoneCut(true);
}
}
}
// The zone's SOA record is the first record in the answer section.
ResourceRecord soa = (ResourceRecord) rrs.answer.firstElement();
synchronized (this) {
contentsRef = new SoftReference(newContents);
serialNumber = getSerialNumber(soa);
setExpiration(getMinimumTtl(soa));
return newContents;
}
}
/*
* Set this zone's data to expire in <tt>secsToExpiration</tt> seconds.
*/
private void setExpiration(long secsToExpiration) {
expiration = new Date(System.currentTimeMillis() +
1000 * secsToExpiration);
}
/*
* Returns an SOA record's minimum TTL field.
*/
private static long getMinimumTtl(ResourceRecord soa) {
String rdata = (String) soa.getRdata();
int pos = rdata.lastIndexOf(' ') + 1;
return Long.parseLong(rdata.substring(pos));
}
/*
* Compares this zone's serial number with that of an SOA record.
* Zone must be populated.
* Returns a negative, zero, or positive integer as this zone's
* serial number is less than, equal to, or greater than the SOA
* record's.
* See ResourceRecord.compareSerialNumbers() for a description of
* serial number arithmetic.
*/
int compareSerialNumberTo(ResourceRecord soa) {
// assert isPopulated();
return ResourceRecord.compareSerialNumbers(serialNumber,
getSerialNumber(soa));
}
/*
* Returns an SOA record's serial number.
*/
private static long getSerialNumber(ResourceRecord soa) {
String rdata = (String) soa.getRdata();
// An SOA record ends with: serial refresh retry expire minimum.
// Set "beg" to the space before serial, and "end" to the space after.
// We go "backward" to avoid dealing with escaped spaces in names.
int beg = rdata.length();
int end = -1;
for (int i = 0; i < 5; i++) {
end = beg;
beg = rdata.lastIndexOf(' ', end - 1);
}
return Long.parseLong(rdata.substring(beg + 1, end));
}
}