Example usage for java.io FileInputStream getChannel

List of usage examples for java.io FileInputStream getChannel

Introduction

In this page you can find the example usage for java.io FileInputStream getChannel.

Prototype

public FileChannel getChannel() 

Source Link

Document

Returns the unique java.nio.channels.FileChannel FileChannel object associated with this file input stream.

Usage

From source file:Main.java

public static void main(String[] args) throws Exception {
    FileInputStream fis = new FileInputStream("test.txt");
    FileChannel fc = fis.getChannel();

    long startRegion = 0;
    long endRegion = fc.size();
    MappedByteBuffer mbb = fc.map(FileChannel.MapMode.READ_ONLY, startRegion, endRegion);
    while (mbb.hasRemaining()) {
        System.out.print((char) mbb.get());
    }//w w w. j a va2s. c o  m
    fis.close();
}

From source file:Main.java

public static void main(String args[]) throws Exception {
    FileInputStream fIn = new FileInputStream("test.txt");
    FileChannel fChan = fIn.getChannel();

    long fSize = fChan.size();
    ByteBuffer mBuf = ByteBuffer.allocate((int) fSize);

    fChan.read(mBuf, 10);/*from w w w.  ja  va2 s .  c  o m*/
    mBuf.rewind();

    for (int i = 0; i < fSize; i++) {
        System.out.print((char) mBuf.get());
    }
    fChan.close();
    fIn.close();
}

From source file:Main.java

public static void main(String args[]) throws Exception {
    FileInputStream fIn = new FileInputStream("test.txt");
    FileChannel fChan = fIn.getChannel();

    long fSize = fChan.size();
    ByteBuffer mBuf = ByteBuffer.allocate((int) fSize);

    fChan.read(mBuf);//from  w w w  .  j a  v a 2s.  c o  m
    mBuf.rewind();

    for (int i = 0; i < fSize; i++) {
        System.out.print((char) mBuf.get());
    }
    fChan.close();
    fIn.close();
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    File aFile = new File("C:/test.bin");
    FileInputStream inFile = new FileInputStream(aFile);
    FileChannel inChannel = inFile.getChannel();
    final int PRIMECOUNT = 6;
    ByteBuffer buf = ByteBuffer.allocate(8 * PRIMECOUNT);
    long[] primes = new long[PRIMECOUNT];
    while (inChannel.read(buf) != -1) {
        ((ByteBuffer) (buf.flip())).asLongBuffer().get(primes);
        for (long prime : primes) {
            System.out.printf("%10d", prime);
        }// www. j  a v  a  2s  . c  o m
        buf.clear();
    }
    inFile.close();
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    Pattern pattern = Pattern.compile("pattern");
    FileInputStream input = new FileInputStream("file.txt");
    FileChannel channel = input.getChannel();

    ByteBuffer bbuf = channel.map(FileChannel.MapMode.READ_ONLY, 0, (int) channel.size());
    CharBuffer cbuf = Charset.forName("8859_1").newDecoder().decode(bbuf);

    Matcher matcher = pattern.matcher(cbuf);
    while (matcher.find()) {
        String match = matcher.group();
        System.out.println(match);
    }/*from ww  w .  jav  a2s .com*/
}

From source file:Main.java

public static void main(String args[]) throws IOException {
    FileInputStream fis = new FileInputStream("FileChannelExample.java");
    FileChannel fc = fis.getChannel();

    ByteBuffer bb = ByteBuffer.allocate((int) fc.size());

    fc.read(bb);/* www  . j ava2 s. c o m*/
    bb.flip();

    String fileContent = new String(bb.array());

    fc.close();
    fc = null;

    System.out.println("fileContent = " + fileContent);
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    File aFile = new File("main.java");
    FileInputStream inFile = new FileInputStream(aFile);
    FileChannel inChannel = inFile.getChannel();
    ByteBuffer lengthBuf = ByteBuffer.allocate(8);
    while (true) {
        if (inChannel.read(lengthBuf) == -1) {
            break;
        }/* ww w  . ja v a 2 s .c o m*/
        lengthBuf.flip();
        int strLength = (int) lengthBuf.getDouble();
        ByteBuffer buf = ByteBuffer.allocate(2 * strLength + 8);
        if (inChannel.read(buf) == -1) {
            break;
        }
        buf.flip();
        byte[] strChars = new byte[2 * strLength];
        buf.get(strChars);
        System.out.println(strLength);
        System.out.println(ByteBuffer.wrap(strChars).asCharBuffer());
        System.out.println(buf.getLong());
        lengthBuf.clear();
    }
    inFile.close();
}

From source file:BufferConverter.java

public static void main(String[] arguments) {
    try {//from  w ww  .  j a v  a2 s.com
        String data = "friends.dat";
        FileInputStream inData = new FileInputStream(data);
        FileChannel inChannel = inData.getChannel();
        long inSize = inChannel.size();
        ByteBuffer source = ByteBuffer.allocate((int) inSize);
        inChannel.read(source, 0);
        source.position(0);
        for (int i = 0; source.remaining() > 0; i++)
            System.out.print(source.get() + " ");

        source.position(0);
        Charset ascii = Charset.forName("US-ASCII");
        CharsetDecoder toAscii = ascii.newDecoder();
        CharBuffer destination = toAscii.decode(source);
        destination.position(0);
        System.out.println("\n\nNew character data:");
        for (int i = 0; destination.remaining() > 0; i++)
            System.out.print(destination.get());
    } catch (Exception ioe) {
        System.out.println(ioe.getMessage());
    }
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    File aFile = new File("charData.xml");
    FileInputStream inFile = null;

    inFile = new FileInputStream(aFile);

    FileChannel inChannel = inFile.getChannel();
    ByteBuffer buf = ByteBuffer.allocate(48);

    while (inChannel.read(buf) != -1) {
        System.out.println("String read: " + ((ByteBuffer) (buf.flip())).asCharBuffer().get(0));
        buf.clear();/*from w ww  .ja v  a  2 s .c  om*/
    }
    inFile.close();
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    File aFile = new File("primes.txt");
    FileInputStream inFile = new FileInputStream(aFile);
    FileChannel inChannel = inFile.getChannel();
    ByteBuffer buf = ByteBuffer.allocateDirect(1024);
    buf.position(buf.limit());// www .jav a  2s . c  om
    while (true) {
        if (buf.remaining() < 8) {
            if (inChannel.read(buf.compact()) == -1) {
                break;
            }
            buf.flip();
        }
        int strLength = (int) buf.getDouble();
        if (buf.remaining() < 2 * strLength) {
            if (inChannel.read(buf.compact()) == -1) {
                break;
            }
            buf.flip();
        }
        byte[] strChars = new byte[2 * strLength];
        buf.get(strChars);
        if (buf.remaining() < 8) {
            if (inChannel.read(buf.compact()) == -1) {
                break;
            }
            buf.flip();
        }
        System.out.println(strLength);
        System.out.println(ByteBuffer.wrap(strChars).asCharBuffer());
        System.out.println(buf.getLong());
    }
    inFile.close();
}