added stub for new index container heap data structure (purpose: inde…

…x folding)

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@4627 6c8d7289-2bf4-0310-a012-ef5d649a1542

source/de/anomic/index/indexContainerHeap.java

@@ -0,0 +1,347 @@
+// indexContainerHeap.java
+// (C) 2008 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
+// first published 30.03.2008 on http://yacy.net
+//
+// This is a part of YaCy, a peer-to-peer based web search engine
+//
+// $LastChangedDate: 2008-03-14 01:16:04 +0100 (Fr, 14 Mrz 2008) $
+// $LastChangedRevision: 4558 $
+// $LastChangedBy: orbiter $
+//
+// LICENSE
+// 
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// 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, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+package de.anomic.index;
+
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.TreeMap;
+
+import de.anomic.kelondro.kelondroByteOrder;
+import de.anomic.kelondro.kelondroCloneableIterator;
+import de.anomic.kelondro.kelondroRow;
+import de.anomic.kelondro.kelondroRowSet;
+import de.anomic.server.serverMemory;
+import de.anomic.server.logging.serverLog;
+
+public final class indexContainerHeap {
+
+    // class variables
+    private final File databaseRoot;
+    protected final SortedMap<String, indexContainer> cache; // wordhash-container
+    private final serverLog log;
+    private String indexArrayFileName;
+    private kelondroRow payloadrow;
+
+    public indexContainerHeap(File databaseRoot, kelondroRow payloadrow, String dumpname, serverLog log) {
+
+        // creates a new index cache
+        // the cache has a back-end where indexes that do not fit in the cache are flushed
+        this.databaseRoot = databaseRoot;
+        this.cache = Collections.synchronizedSortedMap(new TreeMap<String, indexContainer>(new kelondroByteOrder.StringOrder(payloadrow.getOrdering())));
+        this.log = log;
+        this.indexArrayFileName = dumpname;
+        this.payloadrow = payloadrow;
+
+        // read in dump of last session
+        try {
+            restore();
+        } catch (IOException e){
+            log.logSevere("unable to restore cache dump: " + e.getMessage(), e);
+        }
+    }
+
+    private void dump() throws IOException {
+        log.logConfig("creating dump for index cache '" + indexArrayFileName + "', " + cache.size() + " words (and much more urls)");
+        File indexDumpFile = new File(databaseRoot, indexArrayFileName);
+        if (indexDumpFile.exists()) indexDumpFile.delete();
+        OutputStream os = new BufferedOutputStream(new FileOutputStream(indexDumpFile));
+        long startTime = System.currentTimeMillis();
+        long messageTime = System.currentTimeMillis() + 5000;
+        long wordsPerSecond = 0, wordcount = 0, urlcount = 0;
+        Map.Entry<String, indexContainer> entry;
+        String wordHash;
+        indexContainer container;
+
+        // write wCache
+        synchronized (cache) {
+            Iterator<Map.Entry<String, indexContainer>> i = cache.entrySet().iterator();
+            while (i.hasNext()) {
+                // get entries
+                entry = i.next();
+                wordHash = entry.getKey();
+                container = entry.getValue();
+
+                // put entries on stack
+                if (container != null) {
+                    os.write(wordHash.getBytes());
+                    os.write(container.exportCollection());
+                }
+                wordcount++;
+                i.remove(); // free some mem
+
+                // write a log
+                if (System.currentTimeMillis() > messageTime) {
+                    serverMemory.gc(1000, "indexRAMRI, for better statistic-1"); // for better statistic - thq
+                    wordsPerSecond = wordcount * 1000
+                            / (1 + System.currentTimeMillis() - startTime);
+                    log.logInfo("dump status: " + wordcount
+                            + " words done, "
+                            + (cache.size() / (wordsPerSecond + 1))
+                            + " seconds remaining, free mem = "
+                            + (serverMemory.free() / 1024 / 1024)
+                            + "MB");
+                    messageTime = System.currentTimeMillis() + 5000;
+                }
+            }
+        }
+        os.flush();
+        os.close();
+        log.logInfo("finished dump of ram cache: " + urlcount + " word/URL relations in " + ((System.currentTimeMillis() - startTime) / 1000) + " seconds");
+    }
+
+    private void restore() throws IOException {
+        File indexDumpFile = new File(databaseRoot, indexArrayFileName);
+        if (!(indexDumpFile.exists())) return;
+
+        InputStream is = new BufferedInputStream(new FileInputStream(indexDumpFile));
+
+        long messageTime = System.currentTimeMillis() + 5000;
+        long wordCount = 0;
+        synchronized (cache) {
+            String wordHash;
+            byte[] word = new byte[12];
+            while (is.available() > 0) {
+                // read word
+                is.read(word);
+                wordHash = new String(word);
+                // read collection
+
+                indexContainer container = new indexContainer(wordHash, kelondroRowSet.importRowSet(is, payloadrow));
+                cache.put(wordHash, container);
+                wordCount++;
+                // protect against memory shortage
+                //while (serverMemory.free() < 1000000) {flushFromMem(); java.lang.System.gc();}
+                // write a log
+                if (System.currentTimeMillis() > messageTime) {
+                    serverMemory.gc(1000, "indexRAMRI, for better statistic-2"); // for better statistic - thq
+                    log.logInfo("restoring status: " + wordCount + " words done, free mem = " + (serverMemory.free() / 1024 / 1024) + "MB");
+                    messageTime = System.currentTimeMillis() + 5000;
+                }
+            }
+        }
+        is.close();
+    }
+
+    public int size() {
+        return cache.size();
+    }
+
+    public synchronized int indexSize(String wordHash) {
+        indexContainer cacheIndex = (indexContainer) cache.get(wordHash);
+        if (cacheIndex == null) return 0;
+        return cacheIndex.size();
+    }
+
+    public synchronized kelondroCloneableIterator<indexContainer> wordContainers(String startWordHash, boolean rot) {
+        // we return an iterator object that creates top-level-clones of the indexContainers
+        // in the cache, so that manipulations of the iterated objects do not change
+        // objects in the cache.
+        return new wordContainerIterator(startWordHash, rot);
+    }
+
+    public class wordContainerIterator implements kelondroCloneableIterator<indexContainer> {
+
+        // this class exists, because the wCache cannot be iterated with rotation
+        // and because every indexContainer Object that is iterated must be returned as top-level-clone
+        // so this class simulates wCache.tailMap(startWordHash).values().iterator()
+        // plus the mentioned features
+
+        private boolean rot;
+        private Iterator<indexContainer> iterator;
+
+        public wordContainerIterator(String startWordHash, boolean rot) {
+            this.rot = rot;
+            this.iterator = (startWordHash == null) ? cache.values().iterator() : cache.tailMap(startWordHash).values().iterator();
+            // The collection's iterator will return the values in the order that their corresponding keys appear in the tree.
+        }
+
+        public wordContainerIterator clone(Object secondWordHash) {
+            return new wordContainerIterator((String) secondWordHash, rot);
+        }
+
+        public boolean hasNext() {
+            if (rot) return true;
+            return iterator.hasNext();
+        }
+
+        public indexContainer next() {
+            if (iterator.hasNext()) {
+                return ((indexContainer) iterator.next()).topLevelClone();
+            } else {
+                // rotation iteration
+                if (rot) {
+                    iterator = cache.values().iterator();
+                    return ((indexContainer) iterator.next()).topLevelClone();
+                } else {
+                    return null;
+                }
+            }
+        }
+
+        public void remove() {
+            iterator.remove();
+        }
+
+    }
+
+    public boolean hasContainer(String wordHash) {
+        return cache.containsKey(wordHash);
+    }
+
+    public int sizeContainer(String wordHash) {
+        indexContainer c = (indexContainer) cache.get(wordHash);
+        return (c == null) ? 0 : c.size();
+    }
+
+    public synchronized indexContainer getContainer(String wordHash, Set<String> urlselection) {
+        if (wordHash == null) return null;
+
+        // retrieve container
+        indexContainer container = (indexContainer) cache.get(wordHash);
+
+        // We must not use the container from cache to store everything we find,
+        // as that container remains linked to in the cache and might be changed later
+        // while the returned container is still in use.
+        // create a clone from the container
+        if (container != null) container = container.topLevelClone();
+
+        // select the urlselection
+        if ((urlselection != null) && (container != null)) container.select(urlselection);
+
+        return container;
+    }
+
+    public synchronized indexContainer deleteContainer(String wordHash) {
+        // returns the index that had been deleted
+        indexContainer container = (indexContainer) cache.remove(wordHash);
+        return container;
+    }
+
+    public synchronized boolean removeEntry(String wordHash, String urlHash) {
+        indexContainer c = (indexContainer) cache.get(wordHash);
+        if ((c != null) && (c.remove(urlHash) != null)) {
+            // removal successful
+            if (c.size() == 0) {
+                deleteContainer(wordHash);
+            } else {
+                cache.put(wordHash, c);
+            }
+            return true;
+        }
+        return false;
+    }
+
+    public synchronized int removeEntries(String wordHash, Set<String> urlHashes) {
+        if (urlHashes.size() == 0) return 0;
+        indexContainer c = (indexContainer) cache.get(wordHash);
+        int count;
+        if ((c != null) && ((count = c.removeEntries(urlHashes)) > 0)) {
+            // removal successful
+            if (c.size() == 0) {
+                deleteContainer(wordHash);
+            } else {
+                cache.put(wordHash, c);
+            }
+            return count;
+        }
+        return 0;
+    }
+
+    public synchronized int tryRemoveURLs(String urlHash) {
+        // this tries to delete an index from the cache that has this
+        // urlHash assigned. This can only work if the entry is really fresh
+        // Such entries must be searched in the latest entries
+        int delCount = 0;
+            Iterator<Map.Entry<String, indexContainer>> i = cache.entrySet().iterator();
+            Map.Entry<String, indexContainer> entry;
+            String wordhash;
+            indexContainer c;
+            while (i.hasNext()) {
+                entry = i.next();
+                wordhash = entry.getKey();
+
+                // get container
+                c = entry.getValue();
+                if (c.remove(urlHash) != null) {
+                    if (c.size() == 0) {
+                        i.remove();
+                    } else {
+                        cache.put(wordhash, c); // superfluous?
+                    }
+                    delCount++;
+                }
+            }
+        return delCount;
+    }
+
+    public synchronized void addEntries(indexContainer container) {
+        // this puts the entries into the cache, not into the assortment directly
+        int added = 0;
+        if ((container == null) || (container.size() == 0)) return;
+
+        // put new words into cache
+        String wordHash = container.getWordHash();
+        indexContainer entries = (indexContainer) cache.get(wordHash); // null pointer exception? wordhash != null! must be cache==null
+        if (entries == null) {
+            entries = container.topLevelClone();
+            added = entries.size();
+        } else {
+            added = entries.putAllRecent(container);
+        }
+        if (added > 0) {
+            cache.put(wordHash, entries);
+        }
+        entries = null;
+    }
+
+    public synchronized void addEntry(String wordHash, indexRWIRowEntry newEntry, long updateTime, boolean dhtCase) {
+        indexContainer container = (indexContainer) cache.get(wordHash);
+        if (container == null) container = new indexContainer(wordHash, this.payloadrow, 1);
+        container.put(newEntry);
+        cache.put(wordHash, container);
+    }
+
+    public synchronized void close() {
+        // dump cache
+        try {
+            dump();
+        } catch (IOException e){
+            log.logSevere("unable to dump cache: " + e.getMessage(), e);
+        }
+    }
+}

source/de/anomic/kelondro/kelondroByteOrder.java

@@ -42,7 +42,11 @@ public StringOrder(kelondroByteOrder base) {
     		this.baseOrder = base;
     	}
 
-		public int compare(String s1, String s2) {
+    	public StringOrder(kelondroOrder<byte[]> base) {
+            this.baseOrder = (kelondroByteOrder) base;
+        }
+
+        public int compare(String s1, String s2) {
 			return baseOrder.compare(s1.getBytes(), s2.getBytes());
 		}
 

source/de/anomic/kelondro/kelondroRowCollection.java

@@ -26,6 +26,7 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
@@ -172,6 +173,7 @@ private static kelondroRow exportRow(int chunkcachelength) {
     public synchronized byte[] exportCollection() {
         // returns null if the collection is empty
         trim(false);
+        assert this.size() * this.rowdef.objectsize == this.chunkcache.length;
         kelondroRow row = exportRow(chunkcache.length);
         kelondroRow.Entry entry = row.newEntry();
         assert (sortBound <= chunkcount) : "sortBound = " + sortBound + ", chunkcount = " + chunkcount;
@@ -186,6 +188,22 @@ public synchronized byte[] exportCollection() {
         return entry.bytes();
     }
 
+    public static kelondroRowCollection importCollection(InputStream is, kelondroRow rowdef) throws IOException {
+        byte[] byte2 = new byte[2];
+        byte[] byte4 = new byte[4];
+        is.read(byte4); int size = (int) kelondroNaturalOrder.decodeLong(byte4);
+        is.read(byte2); //short lastread = (short) kelondroNaturalOrder.decodeLong(byte2);
+        is.read(byte2); //short lastwrote = (short) kelondroNaturalOrder.decodeLong(byte2);
+        is.read(byte2); //String orderkey = new String(byte2);
+        is.read(byte2); short ordercol = (short) kelondroNaturalOrder.decodeLong(byte2);
+        is.read(byte2); short orderbound = (short) kelondroNaturalOrder.decodeLong(byte2);
+        assert rowdef.primaryKeyIndex == ordercol;
+        byte[] chunkcache = new byte[size * rowdef.objectsize];
+        int c = is.read(chunkcache);
+        assert c == chunkcache.length;
+        return new kelondroRowCollection(rowdef, size, chunkcache, orderbound);
+    }
+
     public void saveCollection(File file) throws IOException {
         serverFileUtils.copy(exportCollection(), file);
     }