From 6025b6016517c6d898d8957d1d7e03ba71431912 Mon Sep 17 00:00:00 2001 From: tknall Date: Fri, 1 Dec 2006 12:20:24 +0000 Subject: Initial import of release 2.2. git-svn-id: https://joinup.ec.europa.eu/svn/pdf-as/trunk@4 7b5415b0-85f9-ee4d-85bd-d5d0c3b42d1c --- .../org/pdfbox/io/RandomAccessFileInputStream.java | 132 +++++++++++++++++++++ 1 file changed, 132 insertions(+) create mode 100644 src/main/java/org/pdfbox/io/RandomAccessFileInputStream.java (limited to 'src/main/java/org/pdfbox/io/RandomAccessFileInputStream.java') diff --git a/src/main/java/org/pdfbox/io/RandomAccessFileInputStream.java b/src/main/java/org/pdfbox/io/RandomAccessFileInputStream.java new file mode 100644 index 0000000..6589bcb --- /dev/null +++ b/src/main/java/org/pdfbox/io/RandomAccessFileInputStream.java @@ -0,0 +1,132 @@ +/** + * Copyright (c) 2003, www.pdfbox.org + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of pdfbox; nor the names of its + * 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 REGENTS 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 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * http://www.pdfbox.org + * + */ +package org.pdfbox.io; + +import java.io.InputStream; +import java.io.IOException; +import java.io.RandomAccessFile; + +/** + * This class allows a section of a RandomAccessFile to be accessed as an + * input stream. + * + * @author Ben Litchfield (ben@csh.rit.edu) + * @version $Revision: 1.3 $ + */ +public class RandomAccessFileInputStream extends InputStream +{ + private RandomAccessFile file; + private long currentPosition; + private long endPosition; + + /** + * Constructor. + * + * @param raFile The file to read the data from. + * @param startPosition The position in the file that this stream starts. + * @param length The length of the input stream. + */ + public RandomAccessFileInputStream( RandomAccessFile raFile, long startPosition, long length ) + { + file = raFile; + currentPosition = startPosition; + endPosition = currentPosition+length; + } + /** + * @see InputStream#available() + */ + public int available() + { + return (int)(endPosition - currentPosition); + } + /** + * @see InputStream#close() + */ + public void close() + { + //do nothing because we want to leave the random access file open. + } + /** + * @see InputStream#read() + */ + public int read() throws IOException + { + synchronized(file) + { + int retval = -1; + if( currentPosition < endPosition ) + { + file.seek( currentPosition ); + currentPosition++; + retval = file.read(); + } + return retval; + } + } + /** + * @see InputStream#read( byte[], int, int ) + */ + public int read( byte[] b, int offset, int length ) throws IOException + { + //only allow a read of the amount available. + if( length > available() ) + { + length = available(); + } + int amountRead = -1; + //only read if there are bytes actually available, otherwise + //return -1 if the EOF has been reached. + if( available() > 0 ) + { + synchronized(file) + { + file.seek( currentPosition ); + amountRead = file.read( b, offset, length ); + } + } + //update the current cursor position. + if( amountRead > 0 ) + { + currentPosition += amountRead; + } + return amountRead; + } + + /** + * @see InputStream#skip( long ) + */ + public long skip( long amountToSkip ) + { + long amountSkipped = Math.min( amountToSkip, available() ); + currentPosition+= amountSkipped; + return amountSkipped; + } +} \ No newline at end of file -- cgit v1.2.3