Example usage for java.io RandomAccessFile getFilePointer

List of usage examples for java.io RandomAccessFile getFilePointer

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Introduction

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

Prototype

public native long getFilePointer() throws IOException;

Source Link

Document

Returns the current offset in this file.

Usage

From source file:dbseer.comp.process.live.LogTailer.java

/**
 * Read new lines.// w w w. j  a  va  2 s .c  o  m
 *
 * @param reader The file to read
 * @return The new position after the lines have been read
 * @throws java.io.IOException if an I/O error occurs.
 */
private long readLines(RandomAccessFile reader) throws IOException {
    StringBuilder sb = new StringBuilder();

    long pos = reader.getFilePointer();
    long rePos = pos; // position to re-read

    int num;
    boolean seenCR = false;
    while (run && ((num = reader.read(inbuf)) != -1)) {
        for (int i = 0; i < num; i++) {
            byte ch = inbuf[i];
            switch (ch) {
            case '\n':
                seenCR = false; // swallow CR before LF
                listener.handle(sb.toString(), pos + i + 1);
                sb.setLength(0);
                rePos = pos + i + 1;
                break;
            case '\r':
                if (seenCR) {
                    sb.append('\r');
                }
                seenCR = true;
                break;
            default:
                if (seenCR) {
                    seenCR = false; // swallow final CR
                    listener.handle(sb.toString(), pos + i + 1);
                    sb.setLength(0);
                    rePos = pos + i + 1;
                }
                sb.append((char) ch); // add character, not its ascii value
            }
        }

        pos = reader.getFilePointer();
    }

    reader.seek(rePos); // Ensure we can re-read if necessary
    return rePos;
}

From source file:org.fastcatsearch.ir.document.DocumentWriter.java

public Document readDocument(int docNo) throws IOException, IRException {
    long prevPosPos = positionOutput.position();
    long docPos = -1;
    try {// w  w w.j  a  v  a 2  s . c  om
        long positionOffset = ((long) docNo) * IOUtil.SIZE_OF_LONG;
        positionOutput.seek(positionOffset);
        docPos = IOUtil.readLong(positionOutput.getRaf());
    } finally {
        positionOutput.seek(prevPosPos);
    }

    // find a document block
    long prevDocPos = docOutput.position();
    try {
        docOutput.seek(docPos);
        RandomAccessFile raf = docOutput.getRaf();
        int len = IOUtil.readInt(raf);
        long n = raf.getFilePointer();
        InputStream docInput = Channels.newInputStream(docOutput.getRaf().getChannel().position(n));
        //2014-11-26 ?  working ?   ? ? GC ?? OOM ? ?.
        // Stream  .
        InflaterInputStream decompressInputStream = null;
        inflaterOutput.reset();
        int count = -1;
        try {
            BoundedInputStream boundedInputStream = new BoundedInputStream(docInput, len);
            boundedInputStream.setPropagateClose(false);// docInput  .
            decompressInputStream = new InflaterInputStream(boundedInputStream, new Inflater(), 512);
            while ((count = decompressInputStream.read(workingBuffer)) != -1) {
                inflaterOutput.write(workingBuffer, 0, count);
            }
        } finally {
            decompressInputStream.close();
        }
    } finally {
        docOutput.seek(prevDocPos);
    }

    BytesRef bytesRef = inflaterOutput.getBytesRef();
    DataInput bai = new BytesDataInput(bytesRef.bytes, 0, bytesRef.length);

    Document document = new Document(fields.size());
    for (int i = 0; i < fields.size(); i++) {
        FieldSetting fs = fields.get(i);
        Field f = null;
        boolean hasValue = bai.readBoolean();
        if (hasValue) {
            f = fs.createEmptyField();
            f.readRawFrom(bai);
        } else {
            f = fs.createEmptyField();
        }
        if (f != null) {
            String multiValueDelimiter = fs.getMultiValueDelimiter();
            try {
                f.parseIndexable(multiValueDelimiter);
            } catch (FieldDataParseException e) {
                throw new IOException(e);
            }
        }
        document.add(f);
    }
    document.setDocId(docNo);
    return document;
}

From source file:com.baidu.terminator.manager.service.LogServiceImpl.java

@Override
public Log readLog(int linkId, long offset) throws IOException {
    String logFileLocation = LinkLogger.getLogFileLocation(linkId);
    FileUtils.createFile(logFileLocation);

    RandomAccessFile raf = null;
    List<String> lines = new ArrayList<String>();
    long length = 0;

    try {/*from   w  w w .j  ava 2 s . c  o m*/
        raf = new RandomAccessFile(logFileLocation, "r");
        raf.seek(offset);
        length = raf.length();

        long point = raf.getFilePointer();
        while (point < length) {
            String line = raf.readLine();
            String utf8Line = new String(line.getBytes("8859_1"), "utf-8");
            lines.add(utf8Line);

            if (point - offset >= MAX_READ_BYTES) {
                length = point;
                break;
            }
            point = raf.getFilePointer();
        }
    } finally {
        if (raf != null) {
            raf.close();
        }
    }

    Log log = new Log();
    log.setLogLocation(logFileLocation);
    log.setOffset(length);
    log.setContent(lines);
    return log;
}

From source file:com.btoddb.fastpersitentqueue.JournalFileTest.java

@Test
public void testInvalidUUID() throws Exception {
    // can't actuall write an invalid UUID because it's made of two variable length longs
    // only way to get an invalid UUID is to have a truncated file
    JournalFile jf1 = new JournalFile(theFile);
    jf1.initForWriting(new UUID());
    jf1.close();/*ww  w.j  ava2 s.  c  om*/

    // mess up the UUID
    RandomAccessFile raFile = new RandomAccessFile(theFile, "rw");
    Utils.writeInt(raFile, 1);
    Utils.writeInt(raFile, -1);
    raFile.setLength(raFile.getFilePointer());
    raFile.close();
    //        Utils.writeLong(raFile, numberOfEntries.get());

    JournalFile jf2 = new JournalFile(theFile);
    try {
        jf2.initForReading();
        fail("should have found invalid UUID in the form of truncated file");
    } catch (EOFException e) {
        // good!
    }
}

From source file:org.xdi.util.FileUtil.java

/**
 * Writes data in a file on specified position
 * //  www . j  a  v a 2s.  com
 * @param filePath
 * @param position
 * @param data
 * @return
 */
public boolean writeToFile(String filePath, long position, String data) {

    try {
        File f = new File(filePath);
        RandomAccessFile raf;
        raf = new RandomAccessFile(f, "rw");
        raf.seek(position);
        StringBuilder dataAfterPostion = new StringBuilder(data);
        while (raf.getFilePointer() < raf.length()) {
            String line = raf.readLine();
            dataAfterPostion.append(line);
        }
        raf.seek(position);
        raf.writeUTF(dataAfterPostion.toString());
        raf.close();
        return true;
    } catch (FileNotFoundException e) {
        e.printStackTrace();
        return false;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }
}

From source file:com.dotmarketing.servlets.taillog.Tailer.java

/**
 * Read new lines./*from  ww  w  .j  av a 2s .c o  m*/
 *
 * @param reader The file to read
 * @return The new position after the lines have been read
 * @throws java.io.IOException if an I/O error occurs.
 */
private long readLines(RandomAccessFile reader) throws IOException {
    long pos = reader.getFilePointer();
    String line = readLine(reader);
    while (line != null) {
        pos = reader.getFilePointer();
        listener.handle(line);
        line = readLine(reader);
    }
    reader.seek(pos); // Ensure we can re-read if necessary
    return pos;
}

From source file:dk.netarkivet.common.utils.cdx.BinSearch.java

/** Perform a binary search for a string in a file.
 * Returns the position of a line that begins with 'find'.
 * Note that this may not be the first line, if there be duplicates.
 * @param in the RandomAccessFile//  www  . ja v  a 2s  .c  om
 * @param find The String to look for in the above file
 * @throws IOException If some I/O error occurs
 * @return The index of a line matching find, or -1 if none found.
 */
private static long binSearch(RandomAccessFile in, String find) throws IOException {
    // The starting position for the binary search.  Always
    // at the start of a line that's < the wanted line.
    long startpos = 0;
    // Ensure that startpos isn't a match.
    in.seek(startpos);
    String line = in.readLine();
    if (line == null) {
        return -1;
    }
    if (compare(line, find) == 0) {
        return startpos;
    }
    // The ending position for the binary search.  Always
    // *after* a line that >= the wanted line (which also means
    // at the start of a line that's > the wanted line, or at EOF
    long endpos = in.length();

    // Set file pos to first line after middle.
    findMiddleLine(in, startpos, endpos);

    // When done searching, midpos points to a matching line, if any
    // Until the search is done, both endpos and startpos point
    // at non-matching lines (or EOF), and startpos < prevpos < endpos
    long prevpos = in.getFilePointer();
    do {
        line = in.readLine();
        if (line == null) {
            log.debug("Internal: Ran past end of file in '" + in + "' at " + endpos);
            return -1;
        }
        int cmp = compare(line, find);
        if (cmp > 0) {
            endpos = prevpos;
        } else if (cmp < 0) {
            startpos = prevpos;
        } else {
            return prevpos;
        }
        if (startpos == endpos) {
            return -1;
        }
        prevpos = findMiddleLine(in, startpos, endpos);
        if (prevpos == -1) {
            return -1;
        }
    } while (true);
}

From source file:dk.netarkivet.common.utils.cdx.BinSearch.java

/**
 * Return the index of the first line in the file to match 'find'. If the
 * lines in the file are roughly equal length, it reads
 * O(sqrt(n)) lines, where n is the distance from matchingline to the first
 * line.//w  w w.  j a  v a  2s. c  om
 *
 * @param in
 *            The file to search in
 * @param find
 *            The string to match against the first line
 * @param matchingline
 *            The index to start searching from.  This index must be at
 *            the start of a line that matches 'find'
 * @return The offset into the file of the first line matching 'find'.
 *         Guaranteed to be <= matchingline.
 * @throws IOException If the matchingLine < 0 or some I/O error occurs.
 */
private static long findFirstLine(RandomAccessFile in, String find, long matchingline) throws IOException {
    in.seek(matchingline);
    String line = in.readLine();
    if (line == null || compare(line, find) != 0) {
        final String msg = "Internal: Called findFirstLine without a " + "matching line in '" + in + "' byte "
                + matchingline;
        log.warn(msg);
        throw new ArgumentNotValid(msg);
    }
    // Skip backwards in quadratically increasing steps.
    int linelength = line.length();
    long offset = linelength;
    for (int i = 1; matchingline - offset > 0; i++, offset = i * i * linelength) {
        skipToLine(in, matchingline - offset);
        line = in.readLine();
        if (line == null || compare(line, find) != 0) {
            break;
        }
    }
    // Either found start-of-file or a non-matching line
    long pos;
    if (matchingline - offset <= 0) {
        pos = 0;
        in.seek(0);
    } else {
        pos = in.getFilePointer();
    }
    // Seek forwards line by line until the first matching line.
    // This takes no more than sqrt(n) steps since we know there is
    // a matching line that far away by the way we skipped to here.
    while ((line = in.readLine()) != null) {
        if (compare(line, find) == 0) {
            return pos;
        }
        pos = in.getFilePointer();
    }

    return -1;
}

From source file:org.mitre.mpf.mvc.util.tailer.MpfLogTailer.java

/**
 * Read new lines./* www.j av a2  s  . c om*/
 *
 * @param reader The file to read
 * @param maxLines The maximum number of lines to read
 * @return The number of lines read
 * @throws IOException if an I/O error occurs.
 */
private int readLines(RandomAccessFile reader, int maxLines) throws IOException {
    int numLines = 0;
    StringBuilder sb = new StringBuilder();

    long pos = reader.getFilePointer();
    long rePos = pos; // position to re-read

    byte ch;
    boolean seenCR = false;
    while (((ch = (byte) (reader.read())) != -1) && (numLines < maxLines)) {
        switch (ch) {
        case '\n':
            seenCR = false; // swallow CR before LF
            if (listener.handle(sb.toString())) {
                numLines++;
            }
            sb.setLength(0);
            rePos = pos + 1;
            break;
        case '\r':
            if (seenCR) {
                sb.append('\r');
            }
            seenCR = true;
            break;
        default:
            if (seenCR) {
                seenCR = false; // swallow final CR
                if (listener.handle(sb.toString())) {
                    numLines++;
                }
                sb.setLength(0);
                rePos = pos + 1;
            }
            sb.append((char) ch); // add character, not its ascii value
        }

        pos = reader.getFilePointer();
    }

    reader.seek(rePos); // Ensure we can re-read if necessary
    position = rePos;

    return numLines;
}

From source file:com.datasayer.meerkat.MeerJobRunner.java

@SuppressWarnings("unchecked")
@Override/*w w w  .  ja v a2s.  c o  m*/
public void bsp(final BSPPeer<Writable, Writable, Writable, Writable, Writable> peer)
        throws IOException, SyncException, InterruptedException {

    while (true) {
        try {
            long currentTime = System.currentTimeMillis();
            FileSystem fs = FileSystem.get(conf);
            if (!fs.isFile(logPath)) {
                System.out.println("can not read input file");
                return;
            }
            RandomAccessFile file = new RandomAccessFile(logPath.toString(), "r");
            long fileLength = file.length();

            if (fileLength > filePointer) {
                file.seek(filePointer);
                String line = null;
                while (file.length() > file.getFilePointer()) {
                    line = file.readLine();
                    line = new String(line.getBytes("8859_1"), "utf-8");
                    guardMeer.observe(line);
                }
                filePointer = file.getFilePointer();
            } else {
                // nothing to do
            }
            file.close();

            long timeDiff = currentTime - this.lastAggregatedTime;
            if (timeDiff >= this.aggregationInterval) {

                peer.sync();

                if (peer.getPeerName().equals(masterName)) {
                    bossMeer.masterCompute(new Iterator<Writable>() {

                        private final int producedMessages = peer.getNumCurrentMessages();
                        private int consumedMessages = 0;

                        @Override
                        public boolean hasNext() {
                            return producedMessages > consumedMessages;
                        }

                        @Override
                        public Writable next() throws NoSuchElementException {
                            if (consumedMessages >= producedMessages) {
                                throw new NoSuchElementException();
                            }

                            try {
                                consumedMessages++;
                                return peer.getCurrentMessage();
                            } catch (IOException e) {
                                throw new NoSuchElementException();
                            }
                        }

                        @Override
                        public void remove() {
                            // BSPPeer.getCurrentMessage originally deletes a message.
                            // Thus, it doesn't need to throw exception.
                            // throw new UnsupportedOperationException();
                        }

                    }, signalMeer);
                    this.lastAggregatedTime = currentTime;
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}