36 lines
1.1 KiB
Java
36 lines
1.1 KiB
Java
// newio/GetChannel.java
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// (c)2016 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
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// Getting channels from streams
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import java.nio.*;
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import java.nio.channels.*;
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import java.io.*;
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public class GetChannel {
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private static final int BSIZE = 1024;
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public static void main(String[] args) throws Exception {
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// Write a file:
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FileChannel fc =
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new FileOutputStream("data.txt").getChannel();
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fc.write(ByteBuffer.wrap("Some text ".getBytes()));
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fc.close();
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// Add to the end of the file:
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fc =
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new RandomAccessFile("data.txt", "rw").getChannel();
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fc.position(fc.size()); // Move to the end
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fc.write(ByteBuffer.wrap("Some more".getBytes()));
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fc.close();
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// Read the file:
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fc = new FileInputStream("data.txt").getChannel();
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ByteBuffer buff = ByteBuffer.allocate(BSIZE);
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fc.read(buff);
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buff.flip();
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while(buff.hasRemaining())
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System.out.write(buff.get());
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System.out.flush();
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}
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}
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/* Output:
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Some text Some more
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*/
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