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A backward compatibility package for PIAX
The newest version!
/*
* RingVNode.java - A virtual node of ring overlay.
*
* Copyright (c) 2015 Kota Abe / PIAX development team
*
* You can redistribute it and/or modify it under either the terms of
* the AGPLv3 or PIAX binary code license. See the file COPYING
* included in the PIAX package for more in detail.
*
* $Id: MSkipGraph.java 1160 2015-03-15 02:43:20Z teranisi $
*/
package org.piax.gtrans.ov.ring;
import java.io.IOException;
import java.util.Collection;
import java.util.List;
import org.piax.common.DdllKey;
import org.piax.common.Endpoint;
import org.piax.common.subspace.Range;
import org.piax.gtrans.ov.Link;
import org.piax.gtrans.ov.ddll.Node;
import org.piax.gtrans.ov.ddll.Node.InsertPoint;
import org.piax.gtrans.ov.ddll.Node.InsertionResult;
import org.piax.gtrans.ov.ddll.NodeObserver;
import org.piax.gtrans.ov.ring.rq.RQMessage;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* a virtual node in simple ring network.
*
* @param the type of Endpoint in the underlying network.
*/
public class RingVNode implements NodeObserver {
/*--- logger ---*/
private static final Logger logger = LoggerFactory
.getLogger(RingVNode.class);
/** mode of DdllRingVNode */
public static enum VNodeMode {
/** not inserted */
OUT, INSERTING,
/** inserted */
INSERTED,
/** deleting */
DELETING, DELETED
};
public final static int DEFAULT_DDLL_CHECK_PERIOD = 30*1000;
public final static int NUMBER_OF_DDLL_RETRY = 100;
public final static int DDLL_RETRY_INTERVAL = 100;
/*
* DDLL-OPT メモ:
* uがp-q間に挿入しようとしてSetRを送信し，SetRNakを受信するとき，以下の場合がある．
* case 1: p.s != in
* case 2: p < u < p.r ∧ p.r != q
* case 3: p < p.r < u
*
* case 1: wait and retry
* case 2: retry between p and p.r
* case 3: retry from p.r or let application find new insertion point
*/
/** true to turn on DDLL-OPT */
public final static boolean DDLL_OPT = true;
protected final RingManager manager;
final Comparable rawkey;
protected final DdllKey key;
protected Node ddllNode;
protected VNodeMode mode = VNodeMode.OUT;
protected static int getCheckPeriod() {
return DEFAULT_DDLL_CHECK_PERIOD;
}
/**
* create a RingVNode instance.
*
* @param rman the p2p network instance that manages this node
* @param rawkey the key
*/
public RingVNode(RingManager rman, Comparable rawkey) {
this.manager = rman;
this.rawkey = rawkey;
this.key = new DdllKey(rawkey, rman.peerId, 0);
this.ddllNode = rman.manager.createNode(this.key, this);
/* register instance for debug */
// synchronized (DdllRingVNode.class) {
// sgnodes.add(this);
// }
}
public Node getDdllNode() {
return ddllNode;
}
public VNodeMode getMode() {
return mode;
}
public Link getLocalLink() {
return ddllNode.getMyLink();
}
public Link getSuccessor() {
return ddllNode.getRight();
}
public Link getPredecessor() {
return ddllNode.getLeft();
}
// Override me
public Link[] getAllLinks() {
Link[] links =
new Link[] { getPredecessor(), getLocalLink(), getSuccessor()};
return links;
}
/* instances for debug */
// private static ArrayList> sgnodes = new ArrayList>();
/* dump nodes for debug */
// static public synchronized void dump() {
// FileWriter fw = null;
// String fn = "DdllRingVNode-dump-" + System.currentTimeMillis() + ".txt";
// logger.warn("DdllRingVNode dump to{}", fn);
// try {
// fw = new FileWriter(fn);
// } catch (IOException e) {
// logger.error("file open", e);
// return;
// }
// try {
// for (DdllRingVNode sgnode : sgnodes) {
// fw.write("sgnode " + sgnode.rawkey + "\n");
// sgnode.rtLockW();
// for (Tile tile : sgnode.table) {
// fw.write(tile.toString() + "\n");
// }
// sgnode.rtUnlockW();
// }
// } catch (IOException e) {
// logger.error("", e);
// } finally {
// try {
// fw.close();
// } catch (IOException e) {
// logger.error("file close", e);
// }
// }
// }
/*
* reader writer locks
*/
protected void rtLockR() {
manager.rtLockR();
}
protected void rtUnlockR() {
manager.rtUnlockR();
}
protected void rtLockW() {
manager.rtLockW();
}
protected void rtUnlockW() {
manager.rtUnlockW();
}
/**
* insert a key into a ring.
*
* @param introducer 既に挿入済みのノード
* @return 成功したらtrue
* @throws UnavailableException introducerにkeyが存在しない
* @throws IOException introducerとの通信でエラー or insertion failure
*/
@SuppressWarnings("unchecked")
protected boolean addKey(E introducer) throws UnavailableException,
IOException {
logger.trace("ENTRY:");
logger.debug("addKey {}, seed: {}", rawkey, introducer);
if (rawkey == null) {
throw new IllegalArgumentException("null key specified");
}
InsertPoint pos = null;
for (int i = 0; i < NUMBER_OF_DDLL_RETRY; i++) {
try {
if (pos == null) {
pos = manager.findImmedNeighbors(introducer, key,
null, // query
null // XXX TransOptions
);
logger.debug("addKey: pos={}", pos);
}
if (pos == null) {
logger.debug("addKey: inserted as the initial node");
ddllNode.insertAsInitialNode();
mode = VNodeMode.INSERTED;
return true;
}
mode = VNodeMode.INSERTING;
InsertionResult insres = null;
if (ddllNode.isBetween(pos.left.key, pos.right.key)) {
insres = ddllNode.insert(pos);
if (insres.success) {
logger.debug("addKey(key={}): insertion succeeded (i={})",
key, i);
mode = VNodeMode.INSERTED;
return true;
}
} else {
// XXX pos に到達したあと，pos.left, pos.right を取り出すまでの間に
// 別のノードが挿入された。検索からやりなおす。
logger.debug(rawkey + ": not ordered: " + pos);
// wrap around境界にひっかかると全ノードをトラバースする可能性があるので，
// 下記は実行せず、失敗とし、再度挿入場所を検索する。
// inserted = ddllNode.insert(pos.left, 1);
}
mode = VNodeMode.OUT;
if (DDLL_OPT && insres != null && insres.hint != null) {
if (Node.isOrdered(insres.hint.left.key, key,
insres.hint.right.key)) {
// retry immediately
pos = insres.hint;
logger.debug("addKey(key={}): insertion failed (i={}, {})."
+ " retry case 2.", key, i, insres);
continue;
} else {
// retry from insres.hint.right
introducer = (E) insres.hint.right.addr;
pos = null;
logger.debug("addKey(key={}): insertion failed (i={}, {})."
+ " retry case 3.", key, i, insres);
continue;
}
}
logger.debug("addKey(key={}): insertion failed (i={}, {})."
+ " retry case 1.", key, i, insres);
introducer = (E) pos.left.addr;
pos = null;
} catch (TemporaryIOException e) {
System.err.println("addKey(key=" + rawkey + ", got " + e);
logger.debug("addKey(key={}): got {}", rawkey, e);
}
try {
Thread.sleep((long) (DDLL_RETRY_INTERVAL + DDLL_RETRY_INTERVAL
* Math.random()));
} catch (InterruptedException e) {
}
}
logger.debug("addKey(key={}): insertion failed (final)", key);
return false;
}
protected boolean removeKey() {
rtLockW();
if (mode != VNodeMode.INSERTED) {
rtUnlockW();
return false;
}
mode = VNodeMode.DELETING;
rtUnlockW();
ddllNode.delete(NUMBER_OF_DDLL_RETRY);
rtLockW();
mode = VNodeMode.OUT;
rtUnlockW();
return true;
}
@Override
public String toString() {
StringBuilder buf = new StringBuilder();
Comparable k = rawkey;
buf.append("key=" + k);
if (k != null) {
buf.append(" (" + k.getClass().getCanonicalName() + "), ");
}
buf.append("mode=" + mode + "\n");
buf.append(toStringRoutingTable());
return buf.toString();
}
// Override me
public String toStringRoutingTable() {
return ddllNode.toString();
}
public boolean isInserted() {
return (mode == VNodeMode.INSERTED);
}
/**
* get raw key
* @return raw key
*/
public Comparable getRawKey() {
return rawkey;
}
/**
* get DdllKey
* @return DdllKey
*/
public DdllKey getKey() {
return key;
}
public RingManager getManager() {
return manager;
}
public void fixLeftLinks(Link link, List failedLinks, RQMessage msg,
List> failedRanges) {
logger.debug("fixLeftLinks: link={}, failedLinks={}, msg={}, failedRanges={}",
link, failedLinks, msg, failedRanges);
}
/*
* DDLL NodeObserver interfaces
*/
@Override
public void onRightNodeChange(Link prevRight, Link newRight, Object payload) {
logger.debug("{}: rightNodeChanged from {} to {}, {}", key, prevRight,
newRight, payload);
}
@Override
public void payloadNotSent(Object payload) {
logger.debug("{}: payloadNotSent received illgal payload {}", key,
payload);
}
@Override
public boolean onNodeFailure(Collection failedLinks) {
logger.debug("onNodeFailure: {}", failedLinks);
return true; // let DDLL to fix this link
}
@Override
public List suppplyLeftCandidatesForFix() {
return null;
}
}