/*
* Copied from the DnsJava project
*
* Copyright (c) 1998-2011, Brian Wellington.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package io.milton.dns.record;
import io.milton.dns.Name;
import java.io.Serializable;
import java.util.*;
/**
* A set of Records with the same name, type, and class. Also included
* are all RRSIG records signing the data records.
* @see Record
* @see RRSIGRecord
*
* @author Brian Wellington
*/
public class RRset implements Serializable {
private static final long serialVersionUID = -3270249290171239695L;
/*
* rrs contains both normal and RRSIG records, with the RRSIG records
* at the end.
*/
private List rrs;
private short nsigs;
private short position;
/** Creates an empty RRset */
public
RRset() {
rrs = new ArrayList(1);
nsigs = 0;
position = 0;
}
/** Creates an RRset and sets its contents to the specified record */
public
RRset(Record record) {
this();
safeAddRR(record);
}
/** Creates an RRset with the contents of an existing RRset */
public
RRset(RRset rrset) {
synchronized (rrset) {
rrs = (List) ((ArrayList)rrset.rrs).clone();
nsigs = rrset.nsigs;
position = rrset.position;
}
}
private void
safeAddRR(Record r) {
if (!(r instanceof RRSIGRecord)) {
if (nsigs == 0)
rrs.add(r);
else
rrs.add(rrs.size() - nsigs, r);
} else {
rrs.add(r);
nsigs++;
}
}
/** Adds a Record to an RRset */
public synchronized void
addRR(Record r) {
if (rrs.isEmpty()) {
safeAddRR(r);
return;
}
Record first = first();
if (!r.sameRRset(first))
throw new IllegalArgumentException("record does not match " +
"rrset");
if (r.getTTL() != first.getTTL()) {
if (r.getTTL() > first.getTTL()) {
r = r.cloneRecord();
r.setTTL(first.getTTL());
} else {
for (int i = 0; i < rrs.size(); i++) {
Record tmp = (Record) rrs.get(i);
tmp = tmp.cloneRecord();
tmp.setTTL(r.getTTL());
rrs.set(i, tmp);
}
}
}
if (!rrs.contains(r))
safeAddRR(r);
}
/** Deletes a Record from an RRset */
public synchronized void
deleteRR(Record r) {
if (rrs.remove(r) && (r instanceof RRSIGRecord))
nsigs--;
}
/** Deletes all Records from an RRset */
public synchronized void
clear() {
rrs.clear();
position = 0;
nsigs = 0;
}
private synchronized Iterator
iterator(boolean data, boolean cycle) {
int size, start, total;
total = rrs.size();
if (data)
size = total - nsigs;
else
size = nsigs;
if (size == 0)
return Collections.EMPTY_LIST.iterator();
if (data) {
if (!cycle)
start = 0;
else {
if (position >= size)
position = 0;
start = position++;
}
} else {
start = total - nsigs;
}
List list = new ArrayList(size);
if (data) {
list.addAll(rrs.subList(start, size));
if (start != 0)
list.addAll(rrs.subList(0, start));
} else {
list.addAll(rrs.subList(start, total));
}
return list.iterator();
}
/**
* Returns an Iterator listing all (data) records.
* @param cycle If true, cycle through the records so that each Iterator will
* start with a different record.
*/
public synchronized Iterator
rrs(boolean cycle) {
return iterator(true, cycle);
}
/**
* Returns an Iterator listing all (data) records. This cycles through
* the records, so each Iterator will start with a different record.
*/
public synchronized Iterator
rrs() {
return iterator(true, true);
}
/** Returns an Iterator listing all signature records */
public synchronized Iterator
sigs() {
return iterator(false, false);
}
/** Returns the number of (data) records */
public synchronized int
size() {
return rrs.size() - nsigs;
}
/**
* Returns the name of the records
* @see Name
*/
public Name
getName() {
return first().getName();
}
/**
* Returns the type of the records
* @see Type
*/
public int
getType() {
return first().getRRsetType();
}
/**
* Returns the class of the records
* @see DClass
*/
public int
getDClass() {
return first().getDClass();
}
/** Returns the ttl of the records */
public synchronized long
getTTL() {
return first().getTTL();
}
/**
* Returns the first record
* @throws IllegalStateException if the rrset is empty
*/
public synchronized Record
first() {
if (rrs.isEmpty())
throw new IllegalStateException("rrset is empty");
return (Record) rrs.get(0);
}
private String
iteratorToString(Iterator it) {
StringBuilder sb = new StringBuilder();
while (it.hasNext()) {
Record rr = (Record) it.next();
sb.append("[");
sb.append(rr.rdataToString());
sb.append("]");
if (it.hasNext())
sb.append(" ");
}
return sb.toString();
}
/** Converts the RRset to a String */
public String
toString() {
if (rrs == null)
return ("{empty}");
StringBuilder sb = new StringBuilder();
sb.append("{ ");
sb.append(getName()).append(" ");
sb.append(getTTL()).append(" ");
sb.append(DClass.string(getDClass())).append(" ");
sb.append(Type.string(getType())).append(" ");
sb.append(iteratorToString(iterator(true, false)));
if (nsigs > 0) {
sb.append(" sigs: ");
sb.append(iteratorToString(iterator(false, false)));
}
sb.append(" }");
return sb.toString();
}
}