Source code

001/*
002 * $RCSfile: IISRandomAccessIO.java,v $
003 *
004 * 
005 * Copyright (c) 2006 Sun Microsystems, Inc. All  Rights Reserved.
006 * 
007 * Redistribution and use in source and binary forms, with or without
008 * modification, are permitted provided that the following conditions
009 * are met: 
010 * 
011 * - Redistribution of source code must retain the above copyright 
012 *   notice, this  list of conditions and the following disclaimer.
013 * 
014 * - Redistribution in binary form must reproduce the above copyright
015 *   notice, this list of conditions and the following disclaimer in 
016 *   the documentation and/or other materials provided with the
017 *   distribution.
018 * 
019 * Neither the name of Sun Microsystems, Inc. or the names of 
020 * contributors may be used to endorse or promote products derived 
021 * from this software without specific prior written permission.
022 * 
023 * This software is provided "AS IS," without a warranty of any 
024 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND 
025 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, 
026 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
027 * EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL 
028 * NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF 
029 * USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
030 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR 
031 * ANY LOST REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
032 * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
033 * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
034 * INABILITY TO USE THIS SOFTWARE, EVEN IF SUN HAS BEEN ADVISED OF THE
035 * POSSIBILITY OF SUCH DAMAGES. 
036 * 
037 * You acknowledge that this software is not designed or intended for 
038 * use in the design, construction, operation or maintenance of any 
039 * nuclear facility. 
040 *
041 * $Revision: 1.1 $
042 * $Date: 2006/08/08 00:31:47 $
043 * $State: Exp $
044 */
045package com.github.jaiimageio.jpeg2000.impl;
046
047import java.io.IOException;
048import java.nio.ByteOrder;
049
050import javax.imageio.stream.ImageInputStream;
051
052import jj2000.j2k.io.EndianType;
053import jj2000.j2k.io.RandomAccessIO;
054
055/**
056 * A wrapper for converting an <code>ImageInputStream</code> into a
057 * <code>RandomAccessIO</code>. The resulting class is read-only.
058 */
059public class IISRandomAccessIO implements RandomAccessIO {
060
061    /** The <code>ImageInputStream</code> that is wrapped */
062    private ImageInputStream iis;
063
064    /**
065     * Creates a <code>RandomAccessIO</code> instance from the supplied
066     * <code>ImageInputStream</code>.
067     *
068     * @param iis The source <code>ImageInputStream</code>.
069     */
070    public IISRandomAccessIO(ImageInputStream iis) {
071        if (iis == null) {
072            throw new IllegalArgumentException("iis == null!");
073        }
074        this.iis = iis;
075    }
076
077    public void close() throws IOException {
078        iis.close();
079    }
080
081    /**
082     * Returns the stream position clamped to a maximum of
083     * <code>Integer.MAX_VALUE</code>.
084     */
085    public int getPos() throws IOException {
086        long pos = iis.getStreamPosition();
087        return pos > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int)pos;
088    }
089
090    public void seek(int off) throws IOException {
091        iis.seek(off);
092    }
093
094    /**
095     * Returns the length of the data stream.
096     *
097     * <p>If the length of the <code>ImageInputStream</code> is not
098     * <code>-1</code>, then it is returned after being clamped to
099     * a maximum value of <code>Integer.MAX_VALUE</code>. If the
100     * <code>ImageInputStream</code> is <code>-1</code>, the stream
101     * is read to a maximum position of <code>Integer.MAX_VALUE</code>
102     * and its final position is returned. The position of the stream
103     * is unchanged from the value it had prior to the call.</p>
104     */
105    public int length() throws IOException {
106        long len = iis.length();
107
108        // If the length is non-negative, use it.
109        if(len != -1L) {
110            return len > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int)len;
111        }
112
113        // If the length is negative, read until the stream ends.
114        iis.mark();
115        int bufLen = 1024;
116        byte[] buf = new byte[bufLen];
117        long pos = iis.getStreamPosition();
118        while(pos < Integer.MAX_VALUE) {
119            int numRead = iis.read(buf, 0, bufLen);
120            if(numRead == -1) break; // EOF
121            pos += numRead;
122        }
123        iis.reset();
124
125        // Return the last position.
126        return pos > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int)pos;
127    }
128
129    public int read() throws IOException {
130        return iis.read();
131    }
132
133    public void readFully(byte b[], int off, int n) throws IOException {
134        iis.readFully(b, off, n);
135    }
136
137    public int getByteOrdering() {
138        return iis.getByteOrder() == ByteOrder.BIG_ENDIAN ?
139            EndianType.BIG_ENDIAN : EndianType.LITTLE_ENDIAN;
140    }
141
142    public byte readByte() throws IOException {
143        return iis.readByte();
144    }
145
146    public int readUnsignedByte() throws IOException {
147        return iis.readUnsignedByte();
148    }
149
150    public short readShort() throws IOException {
151        return iis.readShort();
152    }
153
154    public int readUnsignedShort() throws IOException {
155        return iis.readUnsignedShort();
156    }
157
158    public int readInt() throws IOException {
159        return iis.readInt();
160    }
161
162    public long readUnsignedInt() throws IOException {
163        return iis.readUnsignedInt();
164    }
165
166    public long readLong() throws IOException {
167        return iis.readLong();
168    }
169
170    public float readFloat() throws IOException {
171        return iis.readFloat();
172    }
173
174    public double readDouble() throws IOException {
175        return iis.readDouble();
176    }
177
178    public int skipBytes(int n) throws IOException {
179        return iis.skipBytes(n);
180    }
181
182    /**
183     * A null operation as writing is not supported.
184     */
185    public void flush() {
186        // Intentionally empty.
187    }
188
189    /**
190     * Throws an <code>IOException</code> as writing is not supported.
191     */
192    public void write(int b) throws IOException {
193        throw new IOException("Writing is not supported!");
194    }
195
196    /**
197     * Throws an <code>IOException</code> as writing is not supported.
198     */
199    public void writeByte(int v) throws IOException {
200        throw new IOException("Writing is not supported!");
201    }
202
203    /**
204     * Throws an <code>IOException</code> as writing is not supported.
205     */
206    public void writeShort(int v) throws IOException {
207        throw new IOException("Writing is not supported!");
208    }
209
210    /**
211     * Throws an <code>IOException</code> as writing is not supported.
212     */
213    public void writeInt(int v) throws IOException {
214        throw new IOException("Writing is not supported!");
215    }
216
217    /**
218     * Throws an <code>IOException</code> as writing is not supported.
219     */
220    public void writeLong(long v) throws IOException {
221        throw new IOException("Writing is not supported!");
222    }
223
224    /**
225     * Throws an <code>IOException</code> as writing is not supported.
226     */
227    public void writeFloat(float v) throws IOException {
228        throw new IOException("Writing is not supported!");
229    }
230
231    /**
232     * Throws an <code>IOException</code> as writing is not supported.
233     */
234    public void writeDouble(double v) throws IOException {
235        throw new IOException("Writing is not supported!");
236    }
237}