001 /* FileCacheImageOutputStream.java -- 002 Copyright (C) 2004 Free Software Foundation, Inc. 003 004 This file is part of GNU Classpath. 005 006 GNU Classpath is free software; you can redistribute it and/or modify 007 it under the terms of the GNU General Public License as published by 008 the Free Software Foundation; either version 2, or (at your option) 009 any later version. 010 011 GNU Classpath is distributed in the hope that it will be useful, but 012 WITHOUT ANY WARRANTY; without even the implied warranty of 013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 General Public License for more details. 015 016 You should have received a copy of the GNU General Public License 017 along with GNU Classpath; see the file COPYING. If not, write to the 018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 019 02110-1301 USA. 020 021 Linking this library statically or dynamically with other modules is 022 making a combined work based on this library. Thus, the terms and 023 conditions of the GNU General Public License cover the whole 024 combination. 025 026 As a special exception, the copyright holders of this library give you 027 permission to link this library with independent modules to produce an 028 executable, regardless of the license terms of these independent 029 modules, and to copy and distribute the resulting executable under 030 terms of your choice, provided that you also meet, for each linked 031 independent module, the terms and conditions of the license of that 032 module. An independent module is a module which is not derived from 033 or based on this library. If you modify this library, you may extend 034 this exception to your version of the library, but you are not 035 obligated to do so. If you do not wish to do so, delete this 036 exception statement from your version. */ 037 038 039 package javax.imageio.stream; 040 041 import java.io.File; 042 import java.io.IOException; 043 import java.io.OutputStream; 044 import java.io.RandomAccessFile; 045 046 /** 047 * @author Michael Koch (konqueror@gmx.de) 048 */ 049 public class FileCacheImageOutputStream extends ImageOutputStreamImpl 050 { 051 private OutputStream stream; 052 private File cacheFile; 053 private RandomAccessFile cache; 054 private long maxPos; 055 056 public FileCacheImageOutputStream(OutputStream s, File cacheDir) 057 throws IOException 058 { 059 stream = s; 060 cacheFile = File.createTempFile("imageio", ".tmp", cacheDir); 061 cache = new RandomAccessFile(cacheFile, "rw"); 062 maxPos = 0; 063 } 064 065 public void close() 066 throws IOException 067 { 068 maxPos = cache.length(); 069 seek(maxPos); 070 flushBefore(maxPos); 071 super.close(); 072 cache.close(); 073 cacheFile.delete(); 074 stream.flush(); 075 stream = null; 076 } 077 078 public boolean isCached() 079 { 080 return true; 081 } 082 083 public boolean isCachedFile() 084 { 085 return true; 086 } 087 088 public boolean isCachedMemory() 089 { 090 return false; 091 } 092 093 public int read() 094 throws IOException 095 { 096 bitOffset = 0; 097 int val = cache.read(); 098 if (val != -1) 099 streamPos++; 100 return val; 101 } 102 103 public int read(byte[] data, int offset, int len) 104 throws IOException 105 { 106 bitOffset = 0; 107 int num = cache.read(data, offset, len); 108 if (num != -1) 109 streamPos += num; 110 return num; 111 } 112 113 public void write(byte[] data, int offset, int len) 114 throws IOException 115 { 116 flushBits(); 117 cache.write(data, offset, len); 118 streamPos += len; 119 maxPos = Math.max(streamPos, maxPos); 120 } 121 122 public void write(int value) 123 throws IOException 124 { 125 flushBits(); 126 cache.write(value); 127 streamPos++; 128 maxPos = Math.max(streamPos, maxPos); 129 } 130 131 public long length() 132 { 133 long l; 134 try 135 { 136 l = cache.length(); 137 } 138 catch (IOException ex) 139 { 140 l = -1; 141 } 142 return l; 143 } 144 145 public void seek(long pos) 146 throws IOException 147 { 148 checkClosed(); 149 if (pos < flushedPos) 150 throw new IndexOutOfBoundsException(); 151 cache.seek(pos); 152 streamPos = cache.getFilePointer(); 153 maxPos = Math.max(streamPos, maxPos); 154 bitOffset = 0; 155 } 156 157 public void flushBefore(long pos) 158 throws IOException 159 { 160 long oldPos = flushedPos; 161 super.flushBefore(pos); 162 long flushed = flushedPos - oldPos; 163 if (flushed > 0) 164 { 165 int len = 512; 166 byte[] buf = new byte[len]; 167 cache.seek(oldPos); 168 while (flushed > 0) 169 { 170 int l = (int) Math.min(flushed, len); 171 cache.readFully(buf, 0, l); 172 stream.write(buf, 0, l); 173 flushed -= l; 174 } 175 stream.flush(); 176 } 177 } 178 }