jaroslav@557: /*
jaroslav@557:  * Copyright (c) 1996, 2011, Oracle and/or its affiliates. All rights reserved.
jaroslav@557:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@557:  *
jaroslav@557:  * This code is free software; you can redistribute it and/or modify it
jaroslav@557:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@557:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@557:  * particular file as subject to the "Classpath" exception as provided
jaroslav@557:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@557:  *
jaroslav@557:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@557:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@557:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@557:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@557:  * accompanied this code).
jaroslav@557:  *
jaroslav@557:  * You should have received a copy of the GNU General Public License version
jaroslav@557:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@557:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@557:  *
jaroslav@557:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@557:  * or visit www.oracle.com if you need additional information or have any
jaroslav@557:  * questions.
jaroslav@557:  */
jaroslav@557: 
jaroslav@557: package java.io;
jaroslav@557: 
jaroslav@560: 
jaroslav@557: 
jaroslav@557: /**
jaroslav@557:  * Reads text from a character-input stream, buffering characters so as to
jaroslav@557:  * provide for the efficient reading of characters, arrays, and lines.
jaroslav@557:  *
jaroslav@557:  * <p> The buffer size may be specified, or the default size may be used.  The
jaroslav@557:  * default is large enough for most purposes.
jaroslav@557:  *
jaroslav@557:  * <p> In general, each read request made of a Reader causes a corresponding
jaroslav@557:  * read request to be made of the underlying character or byte stream.  It is
jaroslav@557:  * therefore advisable to wrap a BufferedReader around any Reader whose read()
jaroslav@557:  * operations may be costly, such as FileReaders and InputStreamReaders.  For
jaroslav@557:  * example,
jaroslav@557:  *
jaroslav@557:  * <pre>
jaroslav@557:  * BufferedReader in
jaroslav@557:  *   = new BufferedReader(new FileReader("foo.in"));
jaroslav@557:  * </pre>
jaroslav@557:  *
jaroslav@557:  * will buffer the input from the specified file.  Without buffering, each
jaroslav@557:  * invocation of read() or readLine() could cause bytes to be read from the
jaroslav@557:  * file, converted into characters, and then returned, which can be very
jaroslav@557:  * inefficient.
jaroslav@557:  *
jaroslav@557:  * <p> Programs that use DataInputStreams for textual input can be localized by
jaroslav@557:  * replacing each DataInputStream with an appropriate BufferedReader.
jaroslav@557:  *
jaroslav@557:  * @see FileReader
jaroslav@557:  * @see InputStreamReader
jaroslav@557:  * @see java.nio.file.Files#newBufferedReader
jaroslav@557:  *
jaroslav@557:  * @author      Mark Reinhold
jaroslav@557:  * @since       JDK1.1
jaroslav@557:  */
jaroslav@557: 
jaroslav@557: public class BufferedReader extends Reader {
jaroslav@557: 
jaroslav@557:     private Reader in;
jaroslav@557: 
jaroslav@557:     private char cb[];
jaroslav@557:     private int nChars, nextChar;
jaroslav@557: 
jaroslav@557:     private static final int INVALIDATED = -2;
jaroslav@557:     private static final int UNMARKED = -1;
jaroslav@557:     private int markedChar = UNMARKED;
jaroslav@557:     private int readAheadLimit = 0; /* Valid only when markedChar > 0 */
jaroslav@557: 
jaroslav@557:     /** If the next character is a line feed, skip it */
jaroslav@557:     private boolean skipLF = false;
jaroslav@557: 
jaroslav@557:     /** The skipLF flag when the mark was set */
jaroslav@557:     private boolean markedSkipLF = false;
jaroslav@557: 
jaroslav@557:     private static int defaultCharBufferSize = 8192;
jaroslav@557:     private static int defaultExpectedLineLength = 80;
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Creates a buffering character-input stream that uses an input buffer of
jaroslav@557:      * the specified size.
jaroslav@557:      *
jaroslav@557:      * @param  in   A Reader
jaroslav@557:      * @param  sz   Input-buffer size
jaroslav@557:      *
jaroslav@557:      * @exception  IllegalArgumentException  If sz is <= 0
jaroslav@557:      */
jaroslav@557:     public BufferedReader(Reader in, int sz) {
jaroslav@557:         super(in);
jaroslav@557:         if (sz <= 0)
jaroslav@557:             throw new IllegalArgumentException("Buffer size <= 0");
jaroslav@557:         this.in = in;
jaroslav@557:         cb = new char[sz];
jaroslav@557:         nextChar = nChars = 0;
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Creates a buffering character-input stream that uses a default-sized
jaroslav@557:      * input buffer.
jaroslav@557:      *
jaroslav@557:      * @param  in   A Reader
jaroslav@557:      */
jaroslav@557:     public BufferedReader(Reader in) {
jaroslav@557:         this(in, defaultCharBufferSize);
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /** Checks to make sure that the stream has not been closed */
jaroslav@557:     private void ensureOpen() throws IOException {
jaroslav@557:         if (in == null)
jaroslav@557:             throw new IOException("Stream closed");
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Fills the input buffer, taking the mark into account if it is valid.
jaroslav@557:      */
jaroslav@557:     private void fill() throws IOException {
jaroslav@557:         int dst;
jaroslav@557:         if (markedChar <= UNMARKED) {
jaroslav@557:             /* No mark */
jaroslav@557:             dst = 0;
jaroslav@557:         } else {
jaroslav@557:             /* Marked */
jaroslav@557:             int delta = nextChar - markedChar;
jaroslav@557:             if (delta >= readAheadLimit) {
jaroslav@557:                 /* Gone past read-ahead limit: Invalidate mark */
jaroslav@557:                 markedChar = INVALIDATED;
jaroslav@557:                 readAheadLimit = 0;
jaroslav@557:                 dst = 0;
jaroslav@557:             } else {
jaroslav@557:                 if (readAheadLimit <= cb.length) {
jaroslav@557:                     /* Shuffle in the current buffer */
jaroslav@557:                     System.arraycopy(cb, markedChar, cb, 0, delta);
jaroslav@557:                     markedChar = 0;
jaroslav@557:                     dst = delta;
jaroslav@557:                 } else {
jaroslav@557:                     /* Reallocate buffer to accommodate read-ahead limit */
jaroslav@557:                     char ncb[] = new char[readAheadLimit];
jaroslav@557:                     System.arraycopy(cb, markedChar, ncb, 0, delta);
jaroslav@557:                     cb = ncb;
jaroslav@557:                     markedChar = 0;
jaroslav@557:                     dst = delta;
jaroslav@557:                 }
jaroslav@557:                 nextChar = nChars = delta;
jaroslav@557:             }
jaroslav@557:         }
jaroslav@557: 
jaroslav@557:         int n;
jaroslav@557:         do {
jaroslav@557:             n = in.read(cb, dst, cb.length - dst);
jaroslav@557:         } while (n == 0);
jaroslav@557:         if (n > 0) {
jaroslav@557:             nChars = dst + n;
jaroslav@557:             nextChar = dst;
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Reads a single character.
jaroslav@557:      *
jaroslav@557:      * @return The character read, as an integer in the range
jaroslav@557:      *         0 to 65535 (<tt>0x00-0xffff</tt>), or -1 if the
jaroslav@557:      *         end of the stream has been reached
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      */
jaroslav@557:     public int read() throws IOException {
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557:             for (;;) {
jaroslav@557:                 if (nextChar >= nChars) {
jaroslav@557:                     fill();
jaroslav@557:                     if (nextChar >= nChars)
jaroslav@557:                         return -1;
jaroslav@557:                 }
jaroslav@557:                 if (skipLF) {
jaroslav@557:                     skipLF = false;
jaroslav@557:                     if (cb[nextChar] == '\n') {
jaroslav@557:                         nextChar++;
jaroslav@557:                         continue;
jaroslav@557:                     }
jaroslav@557:                 }
jaroslav@557:                 return cb[nextChar++];
jaroslav@557:             }
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Reads characters into a portion of an array, reading from the underlying
jaroslav@557:      * stream if necessary.
jaroslav@557:      */
jaroslav@557:     private int read1(char[] cbuf, int off, int len) throws IOException {
jaroslav@557:         if (nextChar >= nChars) {
jaroslav@557:             /* If the requested length is at least as large as the buffer, and
jaroslav@557:                if there is no mark/reset activity, and if line feeds are not
jaroslav@557:                being skipped, do not bother to copy the characters into the
jaroslav@557:                local buffer.  In this way buffered streams will cascade
jaroslav@557:                harmlessly. */
jaroslav@557:             if (len >= cb.length && markedChar <= UNMARKED && !skipLF) {
jaroslav@557:                 return in.read(cbuf, off, len);
jaroslav@557:             }
jaroslav@557:             fill();
jaroslav@557:         }
jaroslav@557:         if (nextChar >= nChars) return -1;
jaroslav@557:         if (skipLF) {
jaroslav@557:             skipLF = false;
jaroslav@557:             if (cb[nextChar] == '\n') {
jaroslav@557:                 nextChar++;
jaroslav@557:                 if (nextChar >= nChars)
jaroslav@557:                     fill();
jaroslav@557:                 if (nextChar >= nChars)
jaroslav@557:                     return -1;
jaroslav@557:             }
jaroslav@557:         }
jaroslav@557:         int n = Math.min(len, nChars - nextChar);
jaroslav@557:         System.arraycopy(cb, nextChar, cbuf, off, n);
jaroslav@557:         nextChar += n;
jaroslav@557:         return n;
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Reads characters into a portion of an array.
jaroslav@557:      *
jaroslav@557:      * <p> This method implements the general contract of the corresponding
jaroslav@557:      * <code>{@link Reader#read(char[], int, int) read}</code> method of the
jaroslav@557:      * <code>{@link Reader}</code> class.  As an additional convenience, it
jaroslav@557:      * attempts to read as many characters as possible by repeatedly invoking
jaroslav@557:      * the <code>read</code> method of the underlying stream.  This iterated
jaroslav@557:      * <code>read</code> continues until one of the following conditions becomes
jaroslav@557:      * true: <ul>
jaroslav@557:      *
jaroslav@557:      *   <li> The specified number of characters have been read,
jaroslav@557:      *
jaroslav@557:      *   <li> The <code>read</code> method of the underlying stream returns
jaroslav@557:      *   <code>-1</code>, indicating end-of-file, or
jaroslav@557:      *
jaroslav@557:      *   <li> The <code>ready</code> method of the underlying stream
jaroslav@557:      *   returns <code>false</code>, indicating that further input requests
jaroslav@557:      *   would block.
jaroslav@557:      *
jaroslav@557:      * </ul> If the first <code>read</code> on the underlying stream returns
jaroslav@557:      * <code>-1</code> to indicate end-of-file then this method returns
jaroslav@557:      * <code>-1</code>.  Otherwise this method returns the number of characters
jaroslav@557:      * actually read.
jaroslav@557:      *
jaroslav@557:      * <p> Subclasses of this class are encouraged, but not required, to
jaroslav@557:      * attempt to read as many characters as possible in the same fashion.
jaroslav@557:      *
jaroslav@557:      * <p> Ordinarily this method takes characters from this stream's character
jaroslav@557:      * buffer, filling it from the underlying stream as necessary.  If,
jaroslav@557:      * however, the buffer is empty, the mark is not valid, and the requested
jaroslav@557:      * length is at least as large as the buffer, then this method will read
jaroslav@557:      * characters directly from the underlying stream into the given array.
jaroslav@557:      * Thus redundant <code>BufferedReader</code>s will not copy data
jaroslav@557:      * unnecessarily.
jaroslav@557:      *
jaroslav@557:      * @param      cbuf  Destination buffer
jaroslav@557:      * @param      off   Offset at which to start storing characters
jaroslav@557:      * @param      len   Maximum number of characters to read
jaroslav@557:      *
jaroslav@557:      * @return     The number of characters read, or -1 if the end of the
jaroslav@557:      *             stream has been reached
jaroslav@557:      *
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      */
jaroslav@557:     public int read(char cbuf[], int off, int len) throws IOException {
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557:             if ((off < 0) || (off > cbuf.length) || (len < 0) ||
jaroslav@557:                 ((off + len) > cbuf.length) || ((off + len) < 0)) {
jaroslav@557:                 throw new IndexOutOfBoundsException();
jaroslav@557:             } else if (len == 0) {
jaroslav@557:                 return 0;
jaroslav@557:             }
jaroslav@557: 
jaroslav@557:             int n = read1(cbuf, off, len);
jaroslav@557:             if (n <= 0) return n;
jaroslav@557:             while ((n < len) && in.ready()) {
jaroslav@557:                 int n1 = read1(cbuf, off + n, len - n);
jaroslav@557:                 if (n1 <= 0) break;
jaroslav@557:                 n += n1;
jaroslav@557:             }
jaroslav@557:             return n;
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Reads a line of text.  A line is considered to be terminated by any one
jaroslav@557:      * of a line feed ('\n'), a carriage return ('\r'), or a carriage return
jaroslav@557:      * followed immediately by a linefeed.
jaroslav@557:      *
jaroslav@557:      * @param      ignoreLF  If true, the next '\n' will be skipped
jaroslav@557:      *
jaroslav@557:      * @return     A String containing the contents of the line, not including
jaroslav@557:      *             any line-termination characters, or null if the end of the
jaroslav@557:      *             stream has been reached
jaroslav@557:      *
jaroslav@557:      * @see        java.io.LineNumberReader#readLine()
jaroslav@557:      *
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      */
jaroslav@557:     String readLine(boolean ignoreLF) throws IOException {
jaroslav@557:         StringBuffer s = null;
jaroslav@557:         int startChar;
jaroslav@557: 
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557:             boolean omitLF = ignoreLF || skipLF;
jaroslav@557: 
jaroslav@557:         bufferLoop:
jaroslav@557:             for (;;) {
jaroslav@557: 
jaroslav@557:                 if (nextChar >= nChars)
jaroslav@557:                     fill();
jaroslav@557:                 if (nextChar >= nChars) { /* EOF */
jaroslav@557:                     if (s != null && s.length() > 0)
jaroslav@557:                         return s.toString();
jaroslav@557:                     else
jaroslav@557:                         return null;
jaroslav@557:                 }
jaroslav@557:                 boolean eol = false;
jaroslav@557:                 char c = 0;
jaroslav@557:                 int i;
jaroslav@557: 
jaroslav@557:                 /* Skip a leftover '\n', if necessary */
jaroslav@557:                 if (omitLF && (cb[nextChar] == '\n'))
jaroslav@557:                     nextChar++;
jaroslav@557:                 skipLF = false;
jaroslav@557:                 omitLF = false;
jaroslav@557: 
jaroslav@557:             charLoop:
jaroslav@557:                 for (i = nextChar; i < nChars; i++) {
jaroslav@557:                     c = cb[i];
jaroslav@557:                     if ((c == '\n') || (c == '\r')) {
jaroslav@557:                         eol = true;
jaroslav@557:                         break charLoop;
jaroslav@557:                     }
jaroslav@557:                 }
jaroslav@557: 
jaroslav@557:                 startChar = nextChar;
jaroslav@557:                 nextChar = i;
jaroslav@557: 
jaroslav@557:                 if (eol) {
jaroslav@557:                     String str;
jaroslav@557:                     if (s == null) {
jaroslav@557:                         str = new String(cb, startChar, i - startChar);
jaroslav@557:                     } else {
jaroslav@557:                         s.append(cb, startChar, i - startChar);
jaroslav@557:                         str = s.toString();
jaroslav@557:                     }
jaroslav@557:                     nextChar++;
jaroslav@557:                     if (c == '\r') {
jaroslav@557:                         skipLF = true;
jaroslav@557:                     }
jaroslav@557:                     return str;
jaroslav@557:                 }
jaroslav@557: 
jaroslav@557:                 if (s == null)
jaroslav@557:                     s = new StringBuffer(defaultExpectedLineLength);
jaroslav@557:                 s.append(cb, startChar, i - startChar);
jaroslav@557:             }
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Reads a line of text.  A line is considered to be terminated by any one
jaroslav@557:      * of a line feed ('\n'), a carriage return ('\r'), or a carriage return
jaroslav@557:      * followed immediately by a linefeed.
jaroslav@557:      *
jaroslav@557:      * @return     A String containing the contents of the line, not including
jaroslav@557:      *             any line-termination characters, or null if the end of the
jaroslav@557:      *             stream has been reached
jaroslav@557:      *
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      *
jaroslav@557:      * @see java.nio.file.Files#readAllLines
jaroslav@557:      */
jaroslav@557:     public String readLine() throws IOException {
jaroslav@557:         return readLine(false);
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Skips characters.
jaroslav@557:      *
jaroslav@557:      * @param  n  The number of characters to skip
jaroslav@557:      *
jaroslav@557:      * @return    The number of characters actually skipped
jaroslav@557:      *
jaroslav@557:      * @exception  IllegalArgumentException  If <code>n</code> is negative.
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      */
jaroslav@557:     public long skip(long n) throws IOException {
jaroslav@557:         if (n < 0L) {
jaroslav@557:             throw new IllegalArgumentException("skip value is negative");
jaroslav@557:         }
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557:             long r = n;
jaroslav@557:             while (r > 0) {
jaroslav@557:                 if (nextChar >= nChars)
jaroslav@557:                     fill();
jaroslav@557:                 if (nextChar >= nChars) /* EOF */
jaroslav@557:                     break;
jaroslav@557:                 if (skipLF) {
jaroslav@557:                     skipLF = false;
jaroslav@557:                     if (cb[nextChar] == '\n') {
jaroslav@557:                         nextChar++;
jaroslav@557:                     }
jaroslav@557:                 }
jaroslav@557:                 long d = nChars - nextChar;
jaroslav@557:                 if (r <= d) {
jaroslav@557:                     nextChar += r;
jaroslav@557:                     r = 0;
jaroslav@557:                     break;
jaroslav@557:                 }
jaroslav@557:                 else {
jaroslav@557:                     r -= d;
jaroslav@557:                     nextChar = nChars;
jaroslav@557:                 }
jaroslav@557:             }
jaroslav@557:             return n - r;
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Tells whether this stream is ready to be read.  A buffered character
jaroslav@557:      * stream is ready if the buffer is not empty, or if the underlying
jaroslav@557:      * character stream is ready.
jaroslav@557:      *
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      */
jaroslav@557:     public boolean ready() throws IOException {
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557: 
jaroslav@557:             /*
jaroslav@557:              * If newline needs to be skipped and the next char to be read
jaroslav@557:              * is a newline character, then just skip it right away.
jaroslav@557:              */
jaroslav@557:             if (skipLF) {
jaroslav@557:                 /* Note that in.ready() will return true if and only if the next
jaroslav@557:                  * read on the stream will not block.
jaroslav@557:                  */
jaroslav@557:                 if (nextChar >= nChars && in.ready()) {
jaroslav@557:                     fill();
jaroslav@557:                 }
jaroslav@557:                 if (nextChar < nChars) {
jaroslav@557:                     if (cb[nextChar] == '\n')
jaroslav@557:                         nextChar++;
jaroslav@557:                     skipLF = false;
jaroslav@557:                 }
jaroslav@557:             }
jaroslav@557:             return (nextChar < nChars) || in.ready();
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Tells whether this stream supports the mark() operation, which it does.
jaroslav@557:      */
jaroslav@557:     public boolean markSupported() {
jaroslav@557:         return true;
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Marks the present position in the stream.  Subsequent calls to reset()
jaroslav@557:      * will attempt to reposition the stream to this point.
jaroslav@557:      *
jaroslav@557:      * @param readAheadLimit   Limit on the number of characters that may be
jaroslav@557:      *                         read while still preserving the mark. An attempt
jaroslav@557:      *                         to reset the stream after reading characters
jaroslav@557:      *                         up to this limit or beyond may fail.
jaroslav@557:      *                         A limit value larger than the size of the input
jaroslav@557:      *                         buffer will cause a new buffer to be allocated
jaroslav@557:      *                         whose size is no smaller than limit.
jaroslav@557:      *                         Therefore large values should be used with care.
jaroslav@557:      *
jaroslav@557:      * @exception  IllegalArgumentException  If readAheadLimit is < 0
jaroslav@557:      * @exception  IOException  If an I/O error occurs
jaroslav@557:      */
jaroslav@557:     public void mark(int readAheadLimit) throws IOException {
jaroslav@557:         if (readAheadLimit < 0) {
jaroslav@557:             throw new IllegalArgumentException("Read-ahead limit < 0");
jaroslav@557:         }
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557:             this.readAheadLimit = readAheadLimit;
jaroslav@557:             markedChar = nextChar;
jaroslav@557:             markedSkipLF = skipLF;
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     /**
jaroslav@557:      * Resets the stream to the most recent mark.
jaroslav@557:      *
jaroslav@557:      * @exception  IOException  If the stream has never been marked,
jaroslav@557:      *                          or if the mark has been invalidated
jaroslav@557:      */
jaroslav@557:     public void reset() throws IOException {
jaroslav@557:         synchronized (lock) {
jaroslav@557:             ensureOpen();
jaroslav@557:             if (markedChar < 0)
jaroslav@557:                 throw new IOException((markedChar == INVALIDATED)
jaroslav@557:                                       ? "Mark invalid"
jaroslav@557:                                       : "Stream not marked");
jaroslav@557:             nextChar = markedChar;
jaroslav@557:             skipLF = markedSkipLF;
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: 
jaroslav@557:     public void close() throws IOException {
jaroslav@557:         synchronized (lock) {
jaroslav@557:             if (in == null)
jaroslav@557:                 return;
jaroslav@557:             in.close();
jaroslav@557:             in = null;
jaroslav@557:             cb = null;
jaroslav@557:         }
jaroslav@557:     }
jaroslav@557: }