java.io.RandomAccessFile Java Examples

The following examples show how to use java.io.RandomAccessFile. You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example #1
Source File: WikipediaTest.java    From minperf with Apache License 2.0 7 votes vote down vote up
private static void largeFile(String fileName) throws IOException {
    if (!new File(fileName).exists()) {
        System.out.println("not found: " + fileName);
        return;
    }
    RandomAccessFile f = new RandomAccessFile(fileName, "r");
    byte[] data = new byte[(int) f.length()];
    f.readFully(data);
    HashSet<Text> set = new HashSet<Text>(40 * 1024 * 1024);
    int end = Text.indexOf(data, 0, '\n');
    Text t = new Text(data, 0, end);
    long time = System.currentTimeMillis();
    while (true) {
        set.add(t);
        if (end >= data.length - 1) {
            break;
        }
        int start = end + 1;
        end = Text.indexOf(data, start, '\n');
        t = new Text(data, start, end - start);
        long now = System.currentTimeMillis();
        if (now - time > 2000) {
            System.out.println("size: " + set.size());
            time = now;
        }
    }
    System.out.println("file: " + fileName);
    System.out.println("size: " + set.size());

    test(set, 8, 14);
    test(set, 8, 10);
    test(set, 8, 16);
    test(set, 8, 12);
}
 
Example #2
Source File: JdpDoSomething.java    From openjdk-8-source with GNU General Public License v2.0 7 votes vote down vote up
public static void printJdpPacket(JdpJmxPacket p) {
    if (getVerbose()) {
        try {
            RandomAccessFile f = new RandomAccessFile("out.dmp", "rw");
            f.write(p.getPacketData());
            f.close();
        } catch (IOException e) {
            System.out.println("Can't write a dump file: " + e);
        }

        System.out.println("Id: " + p.getId());
        System.out.println("Jmx: " + p.getJmxServiceUrl());
        System.out.println("Main: " + p.getMainClass());
        System.out.println("InstanceName: " + p.getInstanceName());
        System.out.println("ProccessId: " + p.getProcessId());
        System.out.println("BroadcastInterval: " + p.getBroadcastInterval());
        System.out.println("Rmi Hostname: " + p.getRmiHostname());

        System.out.flush();
    }
}
 
Example #3
Source File: OldRandomAccessFileTest.java    From j2objc with Apache License 2.0 6 votes vote down vote up
/**
 * java.io.RandomAccessFile#writeChars(java.lang.String)
 */
public void test_writeCharsLjava_lang_String() throws IOException {
    RandomAccessFile raf = new java.io.RandomAccessFile(fileName, "rw");
    raf.writeChars(unihw);
    char[] hchars = new char[unihw.length()];
    unihw.getChars(0, unihw.length(), hchars, 0);
    raf.seek(0);
    for (int i = 0; i < hchars.length; i++)
        assertEquals("Test 1: Incorrect character written or read at index " + i + ";",
                hchars[i], raf.readChar());
    raf.close();
    try {
        raf.writeChars("Already closed.");
        fail("Test 2: IOException expected.");
    } catch (IOException e) {
        // Expected.
    }
}
 
Example #4
Source File: FileChange.java    From Green-Creator with GNU General Public License v2.0 6 votes vote down vote up
public FileChange(File file) throws IOException {
	if(!file.exists()) 
	{
		System.out.println("File not found");
		throw new IOException();
	}
	this.file = file;
	RandomAccessFile rsf = new RandomAccessFile(this.file, "rw");
	this.data = new byte[(int) rsf.length()];
	rsf.read(data);
	int pos = 0;
	while (pos < data.length) {
		instBuf.add(data[pos++]);
	}
	rsf.close();
	getLength();
}
 
Example #5
Source File: BaseRegionLoader.java    From Jupiter with GNU General Public License v3.0 6 votes vote down vote up
public BaseRegionLoader(LevelProvider level, int regionX, int regionZ, String ext) {
    try {
        this.x = regionX;
        this.z = regionZ;
        this.levelProvider = level;
        this.filePath = this.levelProvider.getPath() + "region/r." + regionX + "." + regionZ + "." + ext;
        this.file = new File(this.filePath);
        boolean exists = this.file.exists();
        if (!exists) {
            file.createNewFile();
        }
        this.randomAccessFile = new RandomAccessFile(this.filePath, "rw");
        if (!exists) {
            this.createBlank();
        } else {
            this.loadLocationTable();
        }

        this.lastUsed = System.currentTimeMillis();
    } catch (IOException e) {
        throw new RuntimeException(e);
    }

}
 
Example #6
Source File: TwoBitParser.java    From biojava with GNU Lesser General Public License v2.1 6 votes vote down vote up
public TwoBitParser(File f) throws Exception {
	this.f = f;
	raf = new RandomAccessFile(f,"r");
	long sign = readFourBytes();
	if(sign==0x1A412743) {
		logger.debug("2bit: Normal number architecture");
	}
	else if(sign==0x4327411A) {
		reverse = true;
		logger.debug("2bit: Reverse number architecture");
	}
	else throw new Exception("Wrong start signature in 2BIT format");
	readFourBytes();
	int seq_qnt = (int)readFourBytes();
	readFourBytes();
	seq_names = new String[seq_qnt];
	for(int i=0;i<seq_qnt;i++) {
		int name_len = raf.read();
		char[] chars = new char[name_len];
		for(int j=0;j<name_len;j++) chars[j] = (char)raf.read();
		seq_names[i] = new String(chars);
		long pos = readFourBytes();
		seq2pos.put(seq_names[i],pos);
		logger.debug("2bit: Sequence name=[{}], pos={}", seq_names[i], pos);
	}
}
 
Example #7
Source File: RandomAccessFileDemo.java    From code with Apache License 2.0 6 votes vote down vote up
@Test
public void testRead() throws IOException {
    // 1、创建随机访问流对象
    RandomAccessFile raf = new RandomAccessFile("raf.txt", "rw");
    int i = raf.readInt();
    System.out.println(i);
    // 该文件指针可以通过 getFilePointer方法读取,并通过 seek 方法设置。
    System.out.println("当前文件的指针位置是:" + raf.getFilePointer());

    char ch = raf.readChar();
    System.out.println(ch);
    System.out.println("当前文件的指针位置是:" + raf.getFilePointer());

    String s = raf.readUTF();
    System.out.println(s);
    System.out.println("当前文件的指针位置是:" + raf.getFilePointer());

    // 我不想重头开始了,我就要读取a,怎么办呢?
    raf.seek(4);
    ch = raf.readChar();
    System.out.println(ch);
}
 
Example #8
Source File: FileSystemFileConnection.java    From J2ME-Loader with Apache License 2.0 6 votes vote down vote up
private OutputStream openOutputStream(boolean appendToFile, final long byteOffset) throws IOException {
	throwClosed();
	throwOpenDirectory();

	if (this.opendOutputStream != null) {
		throw new IOException("OutputStream already opened");
	}
	/**
	 * Trying to open more than one InputStream or more than one
	 * OutputStream from a StreamConnection causes an IOException.
	 */
	RandomAccessFile raf = new RandomAccessFile(file, "rw");
	raf.seek(byteOffset);
	return new FileOutputStream(raf.getFD()) {
		@Override
		public void close() throws IOException {
			FileSystemFileConnection.this.opendOutputStream = null;
			super.close();
		}
	};
}
 
Example #9
Source File: AbstractFileCheckpointCollection.java    From tracecompass with Eclipse Public License 2.0 6 votes vote down vote up
/**
 * Marks the index as dirty. Writes an invalid file header, and sets the dirty
 * flag which will cause the new file header to be serialized when the index is
 * disposed.
 */
protected void markDirty() {
    RandomAccessFile randomAccessFile = fRandomAccessFile;
    if (fIsDirty || randomAccessFile == null) {
        return;
    }
    try {
        // Write an invalid version until the very last moment when dispose
        // the index. This is how we know if it's corrupted or not.
        randomAccessFile.seek(0);
        randomAccessFile.writeInt(INVALID_VERSION);
    } catch (IOException e) {
        Activator.logError(MessageFormat.format(Messages.IOErrorWritingHeader, fFile), e);
    }
    fIsDirty = true;
}
 
Example #10
Source File: LockPatternUtils.java    From quickmark with MIT License 6 votes vote down vote up
/**
 * Check to see if a pattern matches the saved pattern. If no pattern
 * exists, always returns true.
 * 
 * @param pattern
 *            The pattern to check.
 * @return Whether the pattern matches the stored one.
 */
public boolean checkPattern(List<LockPatternView.Cell> pattern) {
	try {
		// Read all the bytes from the file
		RandomAccessFile raf = new RandomAccessFile(sLockPatternFilename,
				"r");
		final byte[] stored = new byte[(int) raf.length()];
		int got = raf.read(stored, 0, stored.length);
		raf.close();
		if (got <= 0) {
			return true;
		}
		// Compare the hash from the file with the entered pattern's hash
		return Arrays.equals(stored,
				LockPatternUtils.patternToHash(pattern));
	} catch (FileNotFoundException fnfe) {
		return true;
	} catch (IOException ioe) {
		return true;
	}
}
 
Example #11
Source File: VLCUtil.java    From vlc-example-streamplayer with GNU General Public License v3.0 6 votes vote down vote up
private static boolean readSection(RandomAccessFile in, ElfData elf) throws IOException {
    byte[] bytes = new byte[SECTION_HEADER_SIZE];
    in.seek(elf.e_shoff);

    for (int i = 0; i < elf.e_shnum; ++i) {
        in.readFully(bytes);

        // wrap bytes in a ByteBuffer to force endianess
        ByteBuffer buffer = ByteBuffer.wrap(bytes);
        buffer.order(elf.order);

        int sh_type = buffer.getInt(4); /* Section type */
        if (sh_type != SHT_ARM_ATTRIBUTES)
            continue;

        elf.sh_offset = buffer.getInt(16);  /* Section file offset */
        elf.sh_size = buffer.getInt(20);    /* Section size in bytes */
        return true;
    }

    return false;
}
 
Example #12
Source File: OverlappedTrainingRunner.java    From sgdtk with Apache License 2.0 6 votes vote down vote up
private void passN() throws IOException
{

    // Get FV from file
    randomAccessFile = new RandomAccessFile(getCacheFile(), "r");

    while (randomAccessFile.getFilePointer() < randomAccessFile.length())
    {
        int recordLength = (int) randomAccessFile.readLong();
        packBuffer = growIfNeeded(packBuffer, recordLength);
        randomAccessFile.read(packBuffer, 0, recordLength);
        FeatureVector fv = toFeatureVector();
        // add to ring buffer
        addWithProb(fv);

    }

    randomAccessFile.close();

    signalEndEpoch();

}
 
Example #13
Source File: OldRandomAccessFileTest.java    From j2objc with Apache License 2.0 6 votes vote down vote up
/**
 * java.io.RandomAccessFile#readLine()
 */
public void test_readLine() throws IOException {
    // Test for method java.lang.String java.io.RandomAccessFile.readLine()
    RandomAccessFile raf = new java.io.RandomAccessFile(fileName, "rw");
    String s = "Goodbye\nCruel\nWorld\n";
    raf.write(s.getBytes(), 0, s.length());
    raf.seek(0);

    assertEquals("Test 1: Incorrect line read;", "Goodbye", raf.readLine());
    assertEquals("Test 2: Incorrect line read;", "Cruel", raf.readLine());
    assertEquals("Test 3: Incorrect line read;", "World", raf.readLine());
    assertNull("Test 4: Incorrect line read; null expected.", raf.readLine());

    raf.close();
    try {
        raf.readLine();
        fail("Test 5: IOException expected.");
    } catch (IOException e) {
        // Expected.
    }

}
 
Example #14
Source File: FileIOEngine.java    From hbase with Apache License 2.0 6 votes vote down vote up
@VisibleForTesting
void refreshFileConnection(int accessFileNum, IOException ioe) throws IOException {
  ReentrantLock channelLock = channelLocks[accessFileNum];
  channelLock.lock();
  try {
    FileChannel fileChannel = fileChannels[accessFileNum];
    if (fileChannel != null) {
      // Don't re-open a channel if we were waiting on another
      // thread to re-open the channel and it is now open.
      if (fileChannel.isOpen()) {
        return;
      }
      fileChannel.close();
    }
    LOG.warn("Caught ClosedChannelException accessing BucketCache, reopening file: "
        + filePaths[accessFileNum], ioe);
    rafs[accessFileNum] = new RandomAccessFile(filePaths[accessFileNum], "rw");
    fileChannels[accessFileNum] = rafs[accessFileNum].getChannel();
  } finally{
    channelLock.unlock();
  }
}
 
Example #15
Source File: DiskInitFile.java    From gemfirexd-oss with Apache License 2.0 6 votes vote down vote up
private void openRAF() {
  if (DiskStoreImpl.PREALLOCATE_IF) {
    openRAF2();
    return;
  }
  try {
    this.ifRAF = new RandomAccessFile(this.ifFile, getFileMode());
    long len = this.ifRAF.length();
    if (len != 0) {
      this.ifRAF.seek(len);
    }
  } catch (IOException ex) {
    throw new DiskAccessException(
        LocalizedStrings.DiskRegion_COULD_NOT_OPEN_0.toLocalizedString(this.ifFile
            .getPath()), ex, this.parent);
  }
}
 
Example #16
Source File: BufferUtil.java    From MikuMikuStudio with BSD 2-Clause "Simplified" License 6 votes vote down vote up
private static ByteBuffer createByteBufferFile(int size) {
    try {
        if (tmpDir != null && logger.isLoggable(Level.INFO)) {
            logger.log(Level.INFO, "tmpDir = {0}", tmpDir.getAbsoluteFile());
        }
        File tmpFile = File.createTempFile("pmd","tmp", tmpDir);
        if (logger.isLoggable(Level.INFO)) {
            logger.log(Level.INFO, "tmpFile = {0}", tmpFile.getAbsoluteFile());
        }
        RandomAccessFile os = new RandomAccessFile(tmpFile, "rw");
        os.seek(size);
        os.write(0);
        FileChannel ch = os.getChannel();
        MappedByteBuffer  bb = ch.map(MapMode.READ_WRITE, 0, size);
        os.close();
        ch.close();
        tmpFile.delete();
        bb.order(ByteOrder.nativeOrder());
        return bb;
    } catch(IOException ex) {
        throw new RuntimeException(ex);
    }
}
 
Example #17
Source File: PersistentFile.java    From graphicsfuzz with Apache License 2.0 6 votes vote down vote up
@Override
public byte[] load(String key) {
  String filename = makeFilename(key);

  File file = new File(filename);
  if (!file.exists()) {
    return null;
  }

  byte[] data = null;

  try {
    RandomAccessFile f = new RandomAccessFile(file, "r");
    data = new byte[(int) file.length()];
    f.readFully(data);
    f.close();
  } catch (Exception e) {
    e.printStackTrace();
  }

  return data;
}
 
Example #18
Source File: TrackManager.java    From trekarta with GNU General Public License v3.0 6 votes vote down vote up
/**
 * Saves track properties by modifying only file tail.
 */
public void saveProperties(FileDataSource source) throws Exception {
    Track track = source.tracks.get(0);
    // Prepare new properties tail
    ByteBuffer buffer = ByteBuffer.allocate(getSerializedPropertiesSize(track));
    CodedOutputStream output = CodedOutputStream.newInstance(buffer);
    output.writeBytes(FIELD_NAME, ByteString.copyFromUtf8(track.name));
    output.writeUInt32(FIELD_COLOR, track.style.color);
    output.writeFloat(FIELD_WIDTH, track.style.width);
    output.flush();
    // Modify tail of file
    File file = new File(source.path);
    long createTime = file.lastModified();
    RandomAccessFile access = new RandomAccessFile(file, "rw");
    access.setLength(source.propertiesOffset + 1);
    access.seek(source.propertiesOffset);
    access.write(buffer.array());
    access.close();
    //noinspection ResultOfMethodCallIgnored
    file.setLastModified(createTime);
}
 
Example #19
Source File: JdpDoSomething.java    From openjdk-jdk8u with GNU General Public License v2.0 6 votes vote down vote up
public static void printJdpPacket(JdpJmxPacket p) {
    if (getVerbose()) {
        try {
            RandomAccessFile f = new RandomAccessFile("out.dmp", "rw");
            f.write(p.getPacketData());
            f.close();
        } catch (IOException e) {
            System.out.println("Can't write a dump file: " + e);
        }

        System.out.println("Id: " + p.getId());
        System.out.println("Jmx: " + p.getJmxServiceUrl());
        System.out.println("Main: " + p.getMainClass());
        System.out.println("InstanceName: " + p.getInstanceName());
        System.out.println("ProccessId: " + p.getProcessId());
        System.out.println("BroadcastInterval: " + p.getBroadcastInterval());
        System.out.println("Rmi Hostname: " + p.getRmiHostname());

        System.out.flush();
    }
}
 
Example #20
Source File: TestEventQueueBackingStoreFactory.java    From mt-flume with Apache License 2.0 6 votes vote down vote up
@Test (expected = InvalidProtocolBufferException.class)
public void testCorruptMeta() throws Throwable {
  EventQueueBackingStore backingStore = EventQueueBackingStoreFactory.
          get(checkpoint, 10, "test");
  backingStore.close();
  Assert.assertTrue(checkpoint.exists());
  File metaFile = Serialization.getMetaDataFile(checkpoint);
  Assert.assertTrue(metaFile.length() != 0);
  RandomAccessFile writer = new RandomAccessFile(metaFile, "rw");
  writer.seek(10);
  writer.writeLong(new Random().nextLong());
  writer.getFD().sync();
  writer.close();
  try {
    backingStore = EventQueueBackingStoreFactory.get(checkpoint, 10, "test");
  } catch (BadCheckpointException ex) {
    throw ex.getCause();
  }
}
 
Example #21
Source File: SegmentImpl.java    From xdm with GNU General Public License v2.0 6 votes vote down vote up
public SegmentImpl(String folder, String id, long off, long len, long dwn) throws IOException {
	this.id = id;
	this.id = id;
	this.startOffset = off;
	this.folder = folder;
	this.length = len;
	this.downloaded = dwn;
	this.time1 = System.currentTimeMillis();
	this.time2 = time1;
	this.bytesRead1 = dwn;
	this.bytesRead2 = dwn;
	try {
		outStream = new RandomAccessFile(new File(folder, id), "rw");
		outStream.seek(dwn);
		Logger.log("File opened " + id);
	} catch (IOException e) {
		Logger.log(e);
		if (outStream != null) {
			outStream.close();
		}
		throw new IOException(e);
	}
	this.config = Config.getInstance();
}
 
Example #22
Source File: NNStorage.java    From big-c with Apache License 2.0 6 votes vote down vote up
@Override // Storage
public boolean isPreUpgradableLayout(StorageDirectory sd) throws IOException {
  if (disablePreUpgradableLayoutCheck) {
    return false;
  }

  File oldImageDir = new File(sd.getRoot(), "image");
  if (!oldImageDir.exists()) {
    return false;
  }
  // check the layout version inside the image file
  File oldF = new File(oldImageDir, "fsimage");
  RandomAccessFile oldFile = new RandomAccessFile(oldF, "rws");
  try {
    oldFile.seek(0);
    int oldVersion = oldFile.readInt();
    oldFile.close();
    oldFile = null;
    if (oldVersion < LAST_PRE_UPGRADE_LAYOUT_VERSION)
      return false;
  } finally {
    IOUtils.cleanup(LOG, oldFile);
  }
  return true;
}
 
Example #23
Source File: StreamUtils.java    From netbeans with Apache License 2.0 6 votes vote down vote up
public static void transferFile(
        final File file, 
        final OutputStream out,
        final Progress progress) throws IOException {
    RandomAccessFile in = null;
    
    try {
        transferData(in = new RandomAccessFile(file, "r"), out, progress);
    } finally {
        if (in != null) {
            try {
                in.close();
            } catch (IOException e) {
                ErrorManager.notifyDebug("Cannot close raf", e);
            }
        }
    }
}
 
Example #24
Source File: LossReportTestUtil.java    From aeron with Apache License 2.0 5 votes vote down vote up
public static void verifyLossOccurredForStream(final String aeronDirectoryName, final int streamId)
    throws IOException
{
    final File lossReportFile = LossReportUtil.file(aeronDirectoryName);
    assertTrue(lossReportFile.exists());

    MappedByteBuffer mappedByteBuffer = null;

    try (RandomAccessFile file = new RandomAccessFile(lossReportFile, "r");
        FileChannel channel = file.getChannel())
    {
        mappedByteBuffer = channel.map(READ_ONLY, 0, channel.size());
        final AtomicBuffer buffer = new UnsafeBuffer(mappedByteBuffer);

        final LossReportReader.EntryConsumer lossEntryConsumer = mock(LossReportReader.EntryConsumer.class);
        LossReportReader.read(buffer, lossEntryConsumer);

        verify(lossEntryConsumer).accept(
            longThat((l) -> l > 0),
            longThat((l) -> l > 0),
            anyLong(),
            anyLong(),
            anyInt(),
            eq(streamId),
            any(),
            any());
    }
    finally
    {
        IoUtil.unmap(mappedByteBuffer);
    }
}
 
Example #25
Source File: MemoryMappedFileManager.java    From logging-log4j2 with Apache License 2.0 5 votes vote down vote up
protected MemoryMappedFileManager(final RandomAccessFile file, final String fileName, final OutputStream os,
        final boolean immediateFlush, final long position, final int regionLength, final String advertiseURI,
        final Layout<? extends Serializable> layout, final boolean writeHeader) throws IOException {
    super(os, fileName, layout, writeHeader, ByteBuffer.wrap(new byte[0]));
    this.immediateFlush = immediateFlush;
    this.randomAccessFile = Objects.requireNonNull(file, "RandomAccessFile");
    this.regionLength = regionLength;
    this.advertiseURI = advertiseURI;
    this.isEndOfBatch.set(Boolean.FALSE);
    this.mappedBuffer = mmap(randomAccessFile.getChannel(), getFileName(), position, regionLength);
    this.byteBuffer = mappedBuffer;
    this.mappingOffset = position;
}
 
Example #26
Source File: Utility.java    From petscii-bbs with Mozilla Public License 2.0 5 votes vote down vote up
/**
 * @param file
 *            file to check
 * @return true if file seems to be gzipped.
 * @throws CbmException
 *             if error
 */
public static boolean isGZipped(String file) throws CbmException {
	try (RandomAccessFile raf = new RandomAccessFile(file, "r")) {
		return GZIPInputStream.GZIP_MAGIC == (raf.read() & 0xff | ((raf.read() << 8) & 0xff00));
	} catch (IOException e) {
		throw new CbmException("Failed to open zip header. " + e.getMessage(), e);
	}
}
 
Example #27
Source File: LogFile.java    From mt-flume with Apache License 2.0 5 votes vote down vote up
protected static byte[] readDelimitedBuffer(RandomAccessFile fileHandle)
    throws IOException {
  int length = fileHandle.readInt();
  Preconditions.checkState(length >= 0, Integer.toHexString(length));
  byte[] buffer = new byte[length];
  fileHandle.readFully(buffer);
  return buffer;
}
 
Example #28
Source File: SpringBootExecutableStripper.java    From reproducible-build-maven-plugin with Apache License 2.0 5 votes vote down vote up
private byte[] extractLaunchScript(File file) throws IOException
{
    final int startZipOffset;
    try (RandomAccessFile raf = new RandomAccessFile(file, "r"))
    {
        int nextZipFileHeaderPos = 0;
        int matches = 0;
        while (matches != ZIP_FILE_HEADER.length)
        {
            int b = raf.read();
            if (b == -1)
            {
                throw new IOException("Cannot extract launch script");
            }
            if (b == ZIP_FILE_HEADER[nextZipFileHeaderPos])
            {
                matches++;
                nextZipFileHeaderPos++;
            }
            else
            {
                matches = 0;
                nextZipFileHeaderPos = 0;
            }
        }
        startZipOffset = (int) raf.getFilePointer() - ZIP_FILE_HEADER.length;
    }
    final byte[] launchScript = new byte[startZipOffset];
    try (FileInputStream is = new FileInputStream(file))
    {
        is.read(launchScript);
    }
    return launchScript;
}
 
Example #29
Source File: Installation.java    From text_converter with GNU General Public License v3.0 5 votes vote down vote up
private static String readInstallationFile(File installation) throws IOException {
    RandomAccessFile f = new RandomAccessFile(installation, "r");
    byte[] bytes = new byte[(int) f.length()];
    f.readFully(bytes);
    f.close();
    return new String(bytes);
}
 
Example #30
Source File: FileLockUtil.java    From oim-fx with MIT License 5 votes vote down vote up
public FileLockData(String filePath) {
	file = new File(filePath);
	try {
		randomAccessFile = new RandomAccessFile(file, "rw");
		fileChannel = randomAccessFile.getChannel();
	} catch (FileNotFoundException e) {
		e.printStackTrace();
	}
}