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Revert "'#2614: Remove BufferedRandomAccessFile, as it does not help here."
This reverts commit 2e7fe94.
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‎iped-engine/src/main/java/iped/engine/io/BufferedRandomAccessFile.java‎

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/*
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* Copyright 2015 The Apache Software Foundation.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package iped.engine.io;
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import java.io.File;
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import java.io.FileNotFoundException;
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import java.io.IOException;
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import java.io.RandomAccessFile;
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/**
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* This class is a version of the one published at
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* https://code.google.com/p/jmzreader/wiki/BufferedRandomAccessFile augmented
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* to handle unsigned bytes. The original class is published under Apache 2.0
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* license. Fix is marked below
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*
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* This is an optimized version of the RandomAccessFile class as described by
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* Nick Zhang on JavaWorld.com. The article can be found at
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* http://www.javaworld.com/javaworld/javatips/jw-javatip26.html
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*
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* @author jg
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*/
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public class BufferedRandomAccessFile extends RandomAccessFile {
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/**
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* Uses a byte instead of a char buffer for efficiency reasons.
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*/
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private final byte[] buffer;
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private int bufend = 0;
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private int bufpos = 0;
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/**
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* The position inside the actual file.
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*/
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private long realpos = 0;
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/**
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* Creates a new instance of the BufferedRandomAccessFile.
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*
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* @param filename
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* The path of the file to open.
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* @param mode
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* Specifies the mode to use ("r", "rw", etc.) See the
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* BufferedLineReader documentation for more information.
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* @param bufsize
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* The buffer size (in bytes) to use.
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* @throws FileNotFoundException
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* If the mode is "r" but the given string does not denote an
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* existing regular file, or if the mode begins with "rw" but the
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* given string does not denote an existing, writable regular file
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* and a new regular file of that name cannot be created, or if some
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* other error occurs while opening or creating the file.
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*/
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public BufferedRandomAccessFile(String filename, String mode, int bufsize) throws FileNotFoundException {
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super(filename, mode);
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buffer = new byte[bufsize];
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}
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/**
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* Creates a new instance of the BufferedRandomAccessFile.
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*
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* @param file
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* The file to open.
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* @param mode
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* Specifies the mode to use ("r", "rw", etc.) See the
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* BufferedLineReader documentation for more information.
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* @param bufsize
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* The buffer size (in bytes) to use.
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* @throws FileNotFoundException
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* If the mode is "r" but the given file path does not denote an
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* existing regular file, or if the mode begins with "rw" but the
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* given file path does not denote an existing, writable regular
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* file and a new regular file of that name cannot be created, or if
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* some other error occurs while opening or creating the file.
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*/
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public BufferedRandomAccessFile(File file, String mode, int bufsize) throws FileNotFoundException {
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super(file, mode);
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buffer = new byte[bufsize];
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public final int read() throws IOException {
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if (bufpos >= bufend && fillBuffer() < 0) {
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return -1;
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}
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if (bufend == 0) {
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return -1;
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}
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// FIX to handle unsigned bytes
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return (buffer[bufpos++] + 256) & 0xFF;
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// End of fix
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}
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/**
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* Reads as much bytes as possible into the internal buffer.
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*
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* @return The total number of bytes read into the buffer, or -1 if there is no
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* more data because the end of the file has been reached.
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* @throws IOException
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* If the first byte cannot be read for any reason other than end of
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* file, or if the random access file has been closed, or if some
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* other I/O error occurs.
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*/
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private int fillBuffer() throws IOException {
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int n = super.read(buffer);
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if (n >= 0) {
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realpos += n;
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bufend = n;
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bufpos = 0;
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}
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return n;
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}
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/**
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* Clears the local buffer.
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*
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* @throws IOException
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* If an I/O error occurs.
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*/
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private void invalidate() throws IOException {
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bufend = 0;
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bufpos = 0;
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realpos = super.getFilePointer();
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public int read(byte[] b, int off, int len) throws IOException {
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int curLen = len; // length of what is left to read (shrinks)
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int curOff = off; // offset where to put read data (grows)
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int totalRead = 0;
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while (true) {
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int leftover = bufend - bufpos;
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if (curLen <= leftover) {
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System.arraycopy(buffer, bufpos, b, curOff, curLen);
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bufpos += curLen;
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return totalRead + curLen;
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}
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// curLen > leftover, we need to read more than what remains in buffer
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System.arraycopy(buffer, bufpos, b, curOff, leftover);
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totalRead += leftover;
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bufpos += leftover;
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if (fillBuffer() > 0) {
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curOff += leftover;
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curLen -= leftover;
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} else {
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if (totalRead == 0) {
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return -1;
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}
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return totalRead;
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}
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}
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public long getFilePointer() throws IOException {
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return realpos - bufend + bufpos;
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public void seek(long pos) throws IOException {
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long n = realpos - pos;
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if (n >= 0 && n <= bufend) {
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bufpos = bufend - (int) n;
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} else {
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super.seek(pos);
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invalidate();
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}
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}
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}
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‎iped-engine/src/main/java/iped/engine/io/ZIPInputStreamFactory.java‎

Lines changed: 4 additions & 5 deletions
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@@ -6,7 +6,6 @@
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import java.io.IOException;
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import java.io.InputStream;
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import java.io.OutputStream;
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import java.io.RandomAccessFile;
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import java.nio.channels.ClosedChannelException;
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import java.nio.channels.SeekableByteChannel;
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import java.nio.charset.StandardCharsets;
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while (true) {
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File segment = new File(file.getParentFile(), namePrefix + ".z" + String.format("%02d", ++num));
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if (segment.exists()) {
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RandomAccessFile raf = new RandomAccessFile(segment, "r");
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channels.add(new ReadOnlyRAFSeekableByteChannel(raf));
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BufferedRandomAccessFile braf = new BufferedRandomAccessFile(segment, "r", UFDR_BUF_SIZE);
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channels.add(new ReadOnlyRAFSeekableByteChannel(braf));
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} else {
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break;
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}
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}
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// main ufdr should be the last one
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RandomAccessFile raf = new RandomAccessFile(file, "r");
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channels.add(new ReadOnlyRAFSeekableByteChannel(raf));
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BufferedRandomAccessFile braf = new BufferedRandomAccessFile(file, "r", UFDR_BUF_SIZE);
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channels.add(new ReadOnlyRAFSeekableByteChannel(braf));
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if (channels.size() == 1) {
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sbc = channels.get(0);

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