checkeddidemo.java

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/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
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 *   - Redistributions in binary form must reproduce the above copyright
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 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.FileNotFoundException;
import java.io.EOFException;

public class CheckedDIDemo {
    public static void main(String[] args) throws IOException {

        Adler32 inChecker = new Adler32();
        Adler32 outChecker = new Adler32();
        CheckedDataInput in = null;
        CheckedDataOutput out = null;

        try {
            in = new CheckedDataInput(
			    new DataInputStream(
                            new FileInputStream("xanadu.txt")),
			    inChecker);
            out = new CheckedDataOutput(
			     new DataOutputStream(
                             new FileOutputStream("outagain.txt")),
			     outChecker);
        } catch (FileNotFoundException e) {
            System.err.println("CheckedIOTest: " + e);
            System.exit(-1);
        } catch (IOException e) {
            System.err.println("CheckedIOTest: " + e);
            System.exit(-1);
        }

        boolean EOF = false;

        while (!EOF) {
            try {
                int c = in.readByte();
                out.write(c);
            } catch (EOFException e) {
                EOF = true;
            }
        }

        System.out.println("Input stream check sum: " +
			   in.getChecksum().getValue());
        System.out.println("Output stream check sum: " +
			   out.getChecksum().getValue());
    }
}