001/*
002 * Copyright 2011-2012 Stephen Connolly.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.jszip.pseudo.io;
018
019import java.io.Closeable;
020import java.io.IOException;
021import java.nio.ByteBuffer;
022
023public abstract class PseudoFileInputChannel implements Closeable {
024
025    public abstract long size() throws IOException;
026
027    public abstract int read(ByteBuffer dst) throws IOException;
028
029    public long transferTo(long position, long count, PseudoFileOutputChannel target) throws IOException {
030        if (position != 0 || count != size()) {
031            throw new UnsupportedOperationException();
032        }
033        ByteBuffer buf = ByteBuffer.allocate(8192);
034        while (read(buf) != -1) {
035            buf.flip();
036            target.write(buf);
037            buf.clear();
038        }
039        return count;
040    }
041
042}