Example usage for java.io RandomAccessFile write

List of usage examples for java.io RandomAccessFile write

Introduction

In this page you can find the example usage for java.io RandomAccessFile write.

Prototype

public void write(byte b[], int off, int len) throws IOException 

Source Link

Document

Writes len bytes from the specified byte array starting at offset off to this file.

Usage

From source file:org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetImpl.java

static private void truncateBlock(File blockFile, File metaFile, long oldlen, long newlen) throws IOException {
    LOG.info("truncateBlock: blockFile=" + blockFile + ", metaFile=" + metaFile + ", oldlen=" + oldlen
            + ", newlen=" + newlen);

    if (newlen == oldlen) {
        return;//from  w w  w  .j av a  2s  .c om
    }
    if (newlen > oldlen) {
        throw new IOException(
                "Cannot truncate block to from oldlen (=" + oldlen + ") to newlen (=" + newlen + ")");
    }

    DataChecksum dcs = BlockMetadataHeader.readHeader(metaFile).getChecksum();
    int checksumsize = dcs.getChecksumSize();
    int bpc = dcs.getBytesPerChecksum();
    long n = (newlen - 1) / bpc + 1;
    long newmetalen = BlockMetadataHeader.getHeaderSize() + n * checksumsize;
    long lastchunkoffset = (n - 1) * bpc;
    int lastchunksize = (int) (newlen - lastchunkoffset);
    byte[] b = new byte[Math.max(lastchunksize, checksumsize)];

    RandomAccessFile blockRAF = new RandomAccessFile(blockFile, "rw");
    try {
        //truncate blockFile 
        blockRAF.setLength(newlen);

        //read last chunk
        blockRAF.seek(lastchunkoffset);
        blockRAF.readFully(b, 0, lastchunksize);
    } finally {
        blockRAF.close();
    }

    //compute checksum
    dcs.update(b, 0, lastchunksize);
    dcs.writeValue(b, 0, false);

    //update metaFile 
    RandomAccessFile metaRAF = new RandomAccessFile(metaFile, "rw");
    try {
        metaRAF.setLength(newmetalen);
        metaRAF.seek(newmetalen - checksumsize);
        metaRAF.write(b, 0, checksumsize);
    } finally {
        metaRAF.close();
    }
}

From source file:org.sbs.util.download.MultiThreadDownload.java

/**
 * // ww  w  . j  a  v  a  2  s  .  c o m
 * @param url
 * @param path
 * @param fileName
 * @return
 * @throws DownLoadException
 */
@SuppressWarnings("unchecked")
public File downLoad(final URL url, String path, String fileName) throws DownLoadException {
    // ??
    this.downLen = -1;
    this.contentLen = 0;
    this.date = new Date();
    this.finished = false;
    try {
        URLConnection con = url.openConnection();
        //?
        this.contentLen = con.getContentLength();
        //??
        if (StringUtils.isBlank(fileName)) {
            fileName = StringUtils.substringAfterLast(url.getPath(), "/");
        }
        //
        File _path = new File(path);
        if (!_path.exists()) {
            _path.mkdirs();
        }
        final File file = new File(path + File.separator + fileName);
        if (file.exists())
            file.delete();
        if (this.threadNum == 0 && this.blockSize > 0) {
            this.threadNum = (int) (contentLen / blockSize);
            if (this.threadNum == 0) {
                this.threadNum = 1;
            }
        }
        long subLen = contentLen / threadNum;
        List<Future<DownLoadBean>> result = Lists.newArrayList();
        for (int i = 0; i < threadNum; i++) {
            final int pos = (int) (i * subLen);
            final int end = (int) ((i + 1) * subLen) - 1;
            final int current = pos;
            Future<DownLoadBean> f = (Future<DownLoadBean>) pool.submit(new Callable<DownLoadBean>() {
                int $pos = pos;
                int $end = end;
                int $current = current;

                @Override
                public DownLoadBean call() throws Exception {
                    //buff
                    BufferedInputStream bis = null;
                    RandomAccessFile fos = null;
                    byte[] buf = new byte[BUFFER_SIZE];
                    URLConnection con = null;
                    try {
                        con = url.openConnection();
                        con.setAllowUserInteraction(true);
                        //???startPosendPos
                        con.setRequestProperty("Range", "bytes=" + $pos + "-" + $end);
                        fos = new RandomAccessFile(file, "rw");
                        //startPos
                        fos.seek($pos);
                        //????curPos???endPos
                        //endPos?
                        bis = new BufferedInputStream(con.getInputStream());
                        while ($current < $end) {
                            int len = bis.read(buf, 0, BUFFER_SIZE);
                            if (len == -1) {
                                break;
                            }
                            fos.write(buf, 0, len);
                            $current = $current + len;
                            if ($current - 1 > $end) {
                                throw new DownLoadException(
                                        "????");
                            }
                            addLen(len);
                        }
                        bis.close();
                        fos.close();
                    } catch (IOException ex) {
                        /* ?????
                        StringBuffer sb = new StringBuffer();
                        sb.append($pos).append("\t").append($current).append("\t").append($end).append("\n");
                         FileUtils.write(new File(file.getAbsolutePath()+".pos"), sb, true);
                         */
                        throw new RuntimeException(ex);
                    }
                    log.debug(this.hashCode() + ":??[" + $pos + "," + $end + "]");
                    return new DownLoadBean($pos, $end, $current);
                }
            });
            result.add(f);
        }
        Long resultTotal = 0L;
        for (Future<DownLoadBean> f : result) {
            DownLoadBean dInfo = f.get();
            resultTotal += dInfo.getCurrent() - dInfo.getPos();
        }
        // ?
        if (contentLen > resultTotal + 1) {
            // ???
            FileUtils.write(new File(down_error_log_file), url.toString() + "\n", true);
            throw new DownLoadException("?");
        } else {
            finished = true;
            return file;
        }
    } catch (IOException | InterruptedException | ExecutionException e) {
        // 
        try {
            FileUtils.write(new File(down_error_log_file), url.toString() + "\n", true);
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        e.printStackTrace();
    }
    return null;
}

From source file:org.commoncrawl.service.crawler.CrawlSegmentLog.java

public static int reconcileLogFile(FileSystem fs, Path logFilePath, int listId, int segmentId,
        CrawlSegmentFPMap segment, File consolidationFile) throws IOException {

    RandomAccessFile consolidationStream = null;

    int consolidationFileItemCount = 0;

    if (consolidationFile != null) {
        consolidationStream = new RandomAccessFile(consolidationFile, "rw");
        consolidationFileItemCount = readerHeader(consolidationFile);
        consolidationStream.seek(consolidationStream.length());
    }/* ww  w  . j  av a  2 s  . c  o m*/

    int processedItemCount = 0;

    FSDataInputStream hdfsInputStream = null;

    try {

        // get the file size on disk 
        long fileSize = fs.getFileStatus(logFilePath).getLen();

        // allocate an array that can hold up to the list size of items ...
        byte[] buffer = new byte[DEFAULT_LOGITEM_LIST_SIZE * LogItem.ItemSize_Bytes];

        // calcuate item count 
        int totalItemCount = (int) ((fileSize - getHeaderSize()) / LogItem.ItemSize_Bytes);

        // get a reader ... 

        hdfsInputStream = fs.open(logFilePath);

        int headerItemCount = readHeader(hdfsInputStream);

        if (headerItemCount != totalItemCount) {
            LOG.warn("CrawlSegmentLog - header item count for log file:" + logFilePath.toString() + " is:"
                    + headerItemCount + " file size indicates:" + totalItemCount);
            totalItemCount = headerItemCount;
        }

        int remainingItemCount = totalItemCount;

        LogItemBuffer itemList = new LogItemBuffer(listId, segmentId);

        while (remainingItemCount != 0) {

            int blockItemCount = Math.min(remainingItemCount, DEFAULT_LOGITEM_LIST_SIZE);

            // and read the data 
            hdfsInputStream.read(buffer, 0, (int) blockItemCount * LogItem.ItemSize_Bytes);
            // and if consolidation stream is valid ... 
            if (consolidationStream != null) {
                // add entries to that stream ... 
                consolidationStream.write(buffer, 0, (int) blockItemCount * LogItem.ItemSize_Bytes);
            }

            // if not a dry run... 
            if (segment != null) {
                // populate the item list   
                itemList.loadFromStream(buffer, blockItemCount);
                // reconcile the list against the segment 
                processedItemCount += reconcileItemList(itemList, segment);
            }
            // reduce item count 
            remainingItemCount -= blockItemCount;
        }

        // finally if consolidation stream is valid ... 
        if (consolidationStream != null) {
            // update the file's header .. 
            writeHeader(consolidationFile, consolidationFileItemCount + totalItemCount);
        }
    } finally {
        if (consolidationStream != null) {
            consolidationStream.close();
        }
        if (hdfsInputStream != null) {
            hdfsInputStream.close();
        }
    }
    return processedItemCount;
}

From source file:com.polyvi.xface.extension.advancedfiletransfer.XFileDownloader.java

@Override
public void transfer(XCallbackContext callbackCtx) {
    initDownloadInfo();//from w  w w  . ja  v a2 s  .c o  m
    if (mState == DOWNLOADING) {
        return;
    }
    mCallbackCtx = callbackCtx;
    if (null == mDownloadInfo) {
        onError(CONNECTION_ERR);
    } else {
        setState(DOWNLOADING);
        new Thread(new Runnable() {
            @Override
            public void run() {
                HttpURLConnection connection = null;
                RandomAccessFile randomAccessFile = null;
                InputStream is = null;
                int retry = RETRY;
                //TODO:?????
                do {
                    int completeSize = mDownloadInfo.getCompleteSize();
                    try {
                        URL url = new URL(mUrl);
                        connection = (HttpURLConnection) url.openConnection();
                        connection.setConnectTimeout(TIME_OUT_MILLISECOND);
                        connection.setRequestMethod("GET");
                        // ?Rangebytes x-;
                        connection.setRequestProperty("Range", "bytes=" + completeSize + "-");
                        //cookie
                        setCookieProperty(connection, mUrl);
                        // ?.temp
                        randomAccessFile = new RandomAccessFile(mLocalFilePath + TEMP_FILE_SUFFIX, "rwd");
                        randomAccessFile.seek(completeSize);
                        // ???
                        is = connection.getInputStream();
                        byte[] buffer = new byte[mBufferSize];
                        int length = -1;
                        while ((length = is.read(buffer)) != -1) {
                            try {
                                randomAccessFile.write(buffer, 0, length);
                            } catch (Exception e) {
                                retry = -1;
                                break;
                            }
                            completeSize += length;
                            onProgressUpdated(completeSize, 0);
                            if (PAUSE == mState) {
                                break;
                            }
                        }
                        if (mDownloadInfo.isDownloadCompleted()) {
                            // ??.temp
                            renameFile(mLocalFilePath + TEMP_FILE_SUFFIX, mLocalFilePath);
                            onSuccess();
                            break;
                        }
                    } catch (IOException e) {
                        if (retry <= 0) {
                            onError(CONNECTION_ERR);
                            XLog.e(CLASS_NAME, e.getMessage());
                        }
                        // ,?1?
                        try {
                            Thread.sleep(RETRY_INTERVAL);
                        } catch (InterruptedException ex) {
                            XLog.e(CLASS_NAME, "sleep be interrupted", ex);
                        }
                    } finally {
                        try {
                            if (null != is) {
                                is.close();
                            }
                            if (null != randomAccessFile) {
                                // new URL??randomAccessFilenull
                                randomAccessFile.close();
                            }
                            if (null != connection) {
                                // new URL??connectionnull
                                connection.disconnect();
                            }
                        } catch (IOException e) {
                            XLog.e(CLASS_NAME, e.getMessage());
                        }
                    }
                } while ((DOWNLOADING == mState) && (0 < retry--));
            }
        }).start();
    }
}

From source file:com.polyvi.xface.extension.advancedfiletransfer.FileDownloader.java

@Override
public void transfer(CallbackContext callbackCtx) {
    initDownloadInfo();/*from   w  w w  .jav a  2  s  .com*/
    if (mState == DOWNLOADING) {
        return;
    }
    mCallbackCtx = callbackCtx;
    if (null == mDownloadInfo) {
        onError(CONNECTION_ERR);
    } else {
        setState(DOWNLOADING);
        new Thread(new Runnable() {
            @Override
            public void run() {
                HttpURLConnection connection = null;
                RandomAccessFile randomAccessFile = null;
                InputStream is = null;
                int retry = RETRY;
                // TODO:?????
                do {
                    int completeSize = mDownloadInfo.getCompleteSize();
                    try {
                        URL url = new URL(mUrl);
                        connection = (HttpURLConnection) url.openConnection();
                        connection.setConnectTimeout(TIME_OUT_MILLISECOND);
                        connection.setRequestMethod("GET");
                        // ?Rangebytes x-;
                        connection.setRequestProperty("Range", "bytes=" + completeSize + "-");
                        // cookie
                        setCookieProperty(connection, mUrl);
                        // ?.temp
                        randomAccessFile = new RandomAccessFile(mLocalFilePath + TEMP_FILE_SUFFIX, "rwd");

                        randomAccessFile.seek(completeSize);
                        // ???
                        is = connection.getInputStream();
                        byte[] buffer = new byte[mBufferSize];
                        int length = -1;
                        while ((length = is.read(buffer)) != -1) {
                            try {
                                randomAccessFile.write(buffer, 0, length);
                            } catch (Exception e) {
                                retry = -1;
                                break;
                            }
                            completeSize += length;
                            onProgressUpdated(completeSize, mDownloadInfo.getTotalSize());
                            mDownloadInfo.setCompleteSize(completeSize);
                            if (PAUSE == mState) {
                                break;
                            }
                        }
                        if (mDownloadInfo.isDownloadCompleted()) {
                            // ??.temp
                            renameFile(mLocalFilePath + TEMP_FILE_SUFFIX, mLocalFilePath);
                            onSuccess();
                            break;
                        }
                    } catch (FileNotFoundException e) {
                        onError(FILE_NOT_FOUND_ERR);
                        XLog.e(CLASS_NAME, e.getMessage());
                    } catch (IOException e) {
                        if (retry <= 0) {
                            onError(CONNECTION_ERR);
                            XLog.e(CLASS_NAME, e.getMessage());
                        }
                        // ,?1?
                        try {
                            Thread.sleep(RETRY_INTERVAL);
                        } catch (InterruptedException ex) {
                            XLog.e(CLASS_NAME, "sleep be interrupted", ex);
                        }
                    } finally {
                        try {
                            if (null != is) {
                                is.close();
                            }
                            if (null != randomAccessFile) {
                                // new URL??randomAccessFilenull
                                randomAccessFile.close();
                            }
                            if (null != connection) {
                                // new URL??connectionnull
                                connection.disconnect();
                            }
                        } catch (IOException e) {
                            XLog.e(CLASS_NAME, e.getMessage());
                        }
                    }
                } while ((DOWNLOADING == mState) && (0 < retry--));
            }
        }).start();
    }
}

From source file:com.hly.component.download.DownloadTransaction.java

public void run() {
    // TODO ?Daemon
    InputStream is = null;/*from  www. j  a  v  a2s.com*/
    HttpURLConnection conn = null;
    RandomAccessFile randomFile = null;
    File tmpFile = null;
    try {
        // ?uri
        tmpFile = new File(mTempLocalUri);
        File parentFile = tmpFile.getParentFile();
        if (!parentFile.exists()) {
            parentFile.mkdirs();
        }
        if (!tmpFile.exists()) {
            tmpFile.createNewFile();
        }
        randomFile = new RandomAccessFile(mTempLocalUri, "rw");
        long fileLength = randomFile.length();
        completeSize = fileLength;

        if (isCancel) {
            return;
        }
        String connUrl = mUri;
        // ?uri????
        // getRedirectUrl(connUrl);
        if (!T.ckIsEmpty(mRedirectUri)) {
            connUrl = mRedirectUri;
        }
        conn = getHttpConnetion(connUrl);
        conn.setRequestProperty("range", "bytes=" + fileLength + "-");
        conn.connect();

        int contentLength = conn.getContentLength();
        totalSize = completeSize + contentLength;
        if (contentLength == -1 || contentLength > 0) {
            //    
            randomFile.seek(fileLength);
            byte[] buffer = new byte[8192];
            is = conn.getInputStream();
            int length = -1;
            while ((length = is.read(buffer)) != -1) {
                if (isCancel) {
                    return;
                }
                randomFile.write(buffer, 0, length);
                completeSize += length;
                notifyProgress(length);
            }
        }
        mTransactionState.setState(TransactionState.SUCCESS);
    } catch (Throwable t) {
        Log.w(TAG, Log.getStackTraceString(t));
    } finally {
        isRunning = false;
        isCancel = false;
        try {
            if (randomFile != null) {
                randomFile.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (is != null) {
            try {
                is.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        if (conn != null) {
            conn.disconnect();
        }

        if (mTransactionState.getState() != TransactionState.SUCCESS) {
            mTransactionState.setState(TransactionState.FAILED);
            Log.e(TAG, "Delivery failed.");
        } else {
            if (tmpFile == null) {
                mTransactionState.setState(TransactionState.FAILED);
            } else {
                File localFile = new File(this.mLocalUri);
                boolean flag = tmpFile.renameTo(localFile);
                if (flag) {
                    Log.d(TAG, "rename pic succ" + this.mLocalUri);
                } else {
                    mTransactionState.setState(TransactionState.FAILED);
                    Log.d(TAG, "rename pic failed" + this.mLocalUri);
                }
            }
        }
        notifyObservers();
    }
}

From source file:FileBaseDataMap.java

/**
 * put Method.<br>//from  www. j  ava2 s.c om
 * 
 * @param key
 * @param value
 * @param hashCode This is a key value hash code
 */
public void put(String key, String value, int hashCode) {
    try {

        File file = dataFileList[hashCode % numberOfDataFiles];

        StringBuffer buf = new StringBuffer(this.fillCharacter(key, keyDataLength));
        buf.append(this.fillCharacter(value, oneDataLength));

        CacheContainer accessor = (CacheContainer) innerCache.get(file.getAbsolutePath());
        RandomAccessFile raf = null;
        BufferedWriter wr = null;

        if (accessor == null || accessor.isClosed == true) {

            raf = new RandomAccessFile(file, "rwd");
            wr = new BufferedWriter(new FileWriter(file, true));
            accessor = new CacheContainer();
            accessor.raf = raf;
            accessor.wr = wr;
            accessor.file = file;
            innerCache.put(file.getAbsolutePath(), accessor);
        } else {

            raf = accessor.raf;
            wr = accessor.wr;
        }

        // KeyData Write File
        for (int tryIdx = 0; tryIdx < 2; tryIdx++) {
            try {
                // Key??
                long dataLineNo = this.getLinePoint(key, raf);

                if (dataLineNo == -1) {

                    wr.write(buf.toString());
                    wr.flush();

                    // The size of an increment
                    this.totalSize.getAndIncrement();
                } else {

                    // ?????1
                    boolean increMentFlg = false;
                    if (this.get(key, hashCode) == null)
                        increMentFlg = true;

                    raf.seek(dataLineNo * (lineDataSize));
                    raf.write(buf.toString().getBytes(), 0, lineDataSize);
                    if (increMentFlg)
                        this.totalSize.getAndIncrement();
                }
                break;
            } catch (IOException ie) {

                // IOException???1????
                if (tryIdx == 1)
                    throw ie;
                try {

                    if (raf != null)
                        raf.close();
                    if (wr != null)
                        wr.close();

                    raf = new RandomAccessFile(file, "rwd");
                    wr = new BufferedWriter(new FileWriter(file, true));
                    accessor = new CacheContainer();
                    accessor.raf = raf;
                    accessor.wr = wr;
                    accessor.file = file;
                    innerCache.put(file.getAbsolutePath(), accessor);
                } catch (Exception e) {
                    throw e;
                }
            }
        }
    } catch (Exception e2) {
        e2.printStackTrace();
    }
}

From source file:org.commoncrawl.service.listcrawler.CrawlList.java

/**
 * serialize metadata to disk /*ww  w.  ja  va  2 s.  com*/
 * @throws IOException
 */
void writeSubDomainMetadataToDisk(CrawlListMetadata subDomainData) throws IOException {

    DataOutputBuffer outputBuffer = new DataOutputBuffer(CrawlListMetadata.Constants.FixedDataSize);

    subDomainData.serialize(outputBuffer, new BinaryProtocol());

    if (outputBuffer.getLength() > CrawlListMetadata.Constants.FixedDataSize) {
        LOG.error("ListMetadata Serialize for List:" + subDomainData.getDomainName() + " > FixedDataSize!!!");
        outputBuffer.reset();
        subDomainData.setDomainName("<<CORRUPT>>");
        subDomainData.serialize(outputBuffer, new BinaryProtocol());
    }

    synchronized (_subDomainMetadataFile) {
        RandomAccessFile file = new RandomAccessFile(_subDomainMetadataFile, "rw");
        try {
            if (subDomainData.getSubDomainDataOffset() == 0) {
                throw new IOException("Data Offset Zero during write!");
            }
            file.seek(subDomainData.getSubDomainDataOffset());
            file.write(outputBuffer.getData(), 0, outputBuffer.getLength());
        } finally {
            file.close();
        }
    }
}

From source file:org.commoncrawl.service.listcrawler.CrawlList.java

private void writeInitialOnDiskItem(URLFP fp, ProxyCrawlHistoryItem historyItem,
        DataOutputStream valueStreamOut, RandomAccessFile stringStream) throws IOException {

    OnDiskCrawlHistoryItem itemOut = onDiskItemFromHistoryItem(fp, historyItem);

    // update string offset ... 
    itemOut._stringsOffset = stringStream.length();
    // write out string data length 
    WritableUtils.writeVInt(stringStream, _stringBuffer1.getLength());
    // write strings to log file
    stringStream.write(_stringBuffer1.getData(), 0, _stringBuffer1.getLength());
    // update timestamp ... 
    itemOut._updateTimestamp = -1;/*from  w ww.ja v a  2s.  c om*/
    // and write to disk 
    itemOut.serialize(valueStreamOut);
}

From source file:org.commoncrawl.service.listcrawler.CrawlList.java

/**
 * update list state of a recently crawled item 
 * /*from   w w w.  j  av  a 2  s  .co m*/
 * @param fingerprint - the fingerprint of the updated item 
 * @param newData         - the updated crawl history data for the given item    
 * @throws IOException
 */
@Override
public void updateItemState(URLFP fingerprint, ProxyCrawlHistoryItem newData) throws IOException {

    if (_listState == LoadState.LOADED) {
        // check for membership ... 
        if (_bloomFilter.isPresent(fingerprint)) {

            //LOG.info("UpdateItemState Called for URL:" + newData.getOriginalURL() + " List:" + getListId());

            //LOG.info("UpdateItemState Loading OnDisk Item for URL:" + newData.getOriginalURL() + " List:" + getListId());
            // extract existing item from disk 
            OnDiskCrawlHistoryItem originalItem = loadOnDiskItemForURLFP(fingerprint);

            //if present (null if false cache hit) 
            if (originalItem != null) {

                // build an on disk item data structure for any potential changes ... 
                OnDiskCrawlHistoryItem newItem = onDiskItemFromHistoryItem(fingerprint, newData);

                // set inital offset information 
                newItem._fileOffset = originalItem._fileOffset;
                newItem._stringsOffset = originalItem._stringsOffset;

                // LOG.info("UpdateItemState Comparing OnDisk Item  to New Item for URL:" + newData.getOriginalURL() + " List:" + getListId());
                // compare the two items ... 
                if (!newItem.equals(originalItem)) {
                    //LOG.info("UpdateItemState Items Don't Match for  URL:" + newData.getOriginalURL() + " List:" + getListId());
                    // ok items do not match ... figure out if strings are different ... 
                    if (newItem._stringsCRC != originalItem._stringsCRC) {
                        RandomAccessFile stringsFile = new RandomAccessFile(_variableDataFile, "rw");

                        try {
                            // seek to end 
                            stringsFile.seek(stringsFile.length());
                            // update offset info 
                            newItem._stringsOffset = stringsFile.length();
                            // write out string data length 
                            WritableUtils.writeVInt(stringsFile, _stringBuffer1.getLength());
                            // write strings to log file
                            stringsFile.write(_stringBuffer1.getData(), 0, _stringBuffer1.getLength());
                        } finally {
                            stringsFile.close();
                        }
                    }
                    // otherwise take the offset from old item 
                    else {
                        newItem._stringsOffset = originalItem._stringsOffset;
                    }
                    //LOG.info("Opening Data File for OnDiskItem load for Fingerprint:" + newItem._urlFingerprint);

                    // ok, different paths depending on wether this is an in memory update or not ... 
                    boolean wroteToMemory = false;
                    synchronized (this) {
                        if (_tempFixedDataBuffer != null) {
                            wroteToMemory = true;
                            // reset output buffer 
                            _tempOutputBuffer.reset();
                            // serizlie to output buffer 
                            newItem.serialize(_tempOutputBuffer);
                            // copy to appropriate location 
                            System.arraycopy(_tempOutputBuffer.getData(), 0, _tempFixedDataBuffer,
                                    (int) originalItem._fileOffset, OnDiskCrawlHistoryItem.ON_DISK_SIZE);
                        }
                    }

                    if (!wroteToMemory) {
                        // write to disk 
                        RandomAccessFile file = new RandomAccessFile(_fixedDataFile, "rw");

                        try {

                            while (true) {
                                try {
                                    //LOG.info("*** TRYING UPDATE LOCK FOR OFFSET:" + originalItem._fileOffset);
                                    FileLock lock = file.getChannel().tryLock(originalItem._fileOffset,
                                            OnDiskCrawlHistoryItem.ON_DISK_SIZE, false);

                                    try {
                                        //LOG.info("*** GOT UPDATE LOCK FOR OFFSET:" + originalItem._fileOffset);
                                        file.seek(originalItem._fileOffset);
                                        newItem.serialize(file);
                                        //LOG.info("Updated Data File for OnDiskItem for Fingerprint:" + originalItem._urlFingerprint);
                                        break;
                                    } finally {
                                        //LOG.info("*** RELEASED UPDATE LOCK FOR OFFSET:" + originalItem._fileOffset);
                                        lock.release();
                                    }
                                } catch (OverlappingFileLockException e) {
                                    LOG.error("###LockConflict(RETRY):" + CCStringUtils.stringifyException(e));
                                }
                            }
                        } finally {
                            file.close();
                        }
                    }

                    // ok now update metadata ... 
                    synchronized (_metadata) {

                        int updateFlags = calculateUpdateFlags(originalItem, newItem);

                        if (updateFlags != 0) {

                            int metadataDirtyFlags = updateMetadata(newItem, _metadata, 0);

                            // only write metadata to disk if temp data buffer is null
                            if (metadataDirtyFlags != 0 && !wroteToMemory) {
                                if ((metadataDirtyFlags & MetadataUpdateFlag_ModifiedCrawlStatus) != 0) {
                                    _metadata.setQueuedItemCount(_metadata.getQueuedItemCount() - 1);
                                }
                                writeMetadataToDisk();
                            }

                            // if not writing to memory then update subdomain metadata 
                            if (!wroteToMemory) {

                                synchronized (_subDomainMetadataFile) {
                                    CrawlListMetadata subDomainMetadata = getSubDomainMetadataByURL(
                                            newData.getOriginalURL());

                                    int subDomainMetadataDirtyFlags = updateMetadata(newItem, subDomainMetadata,
                                            processFileOffsets);

                                    if (subDomainMetadataDirtyFlags != 0 && !wroteToMemory) {
                                        if ((subDomainMetadataDirtyFlags
                                                & MetadataUpdateFlag_ModifiedCrawlStatus) != 0) {
                                            subDomainMetadata.setQueuedItemCount(
                                                    subDomainMetadata.getQueuedItemCount() - 1);
                                        }
                                        writeSubDomainMetadataToDisk(subDomainMetadata);
                                    }
                                }
                            }
                        }
                    }

                    synchronized (this) {
                        if (_eventListener != null) {
                            _eventListener.itemUpdated(fingerprint);
                        }
                    }
                }
            }
        }
    }
}