/*

 * Copyright (c) 1996, 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package java.util.zip;

import java.io.FilterOutputStream;

import java.io.OutputStream;

import java.io.IOException;

/**

 * An output stream that also maintains a checksum of the data being

 * written. The checksum can then be used to verify the integrity of

 * the output data.

 *

 * @see         Checksum

 * @author      David Connelly

 * @since 1.1

 */

public class CheckedOutputStream extends FilterOutputStream {

    private Checksum cksum;

    /**

     * Creates an output stream with the specified Checksum.

     * @param out the output stream

     * @param cksum the checksum

     */

    public CheckedOutputStream(OutputStream out, Checksum cksum) {

        super(out);

        this.cksum = cksum;

    }

    /**

     * Writes a byte. Will block until the byte is actually written.

     * @param b the byte to be written

     * @throws    IOException if an I/O error has occurred

     */

    public void write(int b) throws IOException {

        out.write(b);

        cksum.update(b);

    }

    /**

     * Writes an array of bytes. Will block until the bytes are

     * actually written.

     * @param b the data to be written

     * @param off the start offset of the data

     * @param len the number of bytes to be written

     * @throws    IOException if an I/O error has occurred

     */

    public void write(byte[] b, int off, int len) throws IOException {

        out.write(b, off, len);

        cksum.update(b, off, len);

    }

    /**

     * Returns the Checksum for this output stream.

     * @return the Checksum

     */

    public Checksum getChecksum() {

        return cksum;

    }

}