org.argeo.jcr/src/org/argeo/jcr/fs/BinaryChannel.java

   1 package org.argeo.jcr.fs;
   2
   3 import java.io.ByteArrayInputStream;
   4 import java.io.IOException;
   5 import java.io.InputStream;
   6 import java.nio.ByteBuffer;
   7 import java.nio.channels.Channels;
   8 import java.nio.channels.FileChannel;
   9 import java.nio.channels.ReadableByteChannel;
  10 import java.nio.channels.SeekableByteChannel;
  11 import java.nio.file.Files;
  12 import java.nio.file.Path;
  13 import java.nio.file.StandardOpenOption;
  14
  15 import javax.jcr.Binary;
  16 import javax.jcr.Node;
  17 import javax.jcr.Property;
  18 import javax.jcr.RepositoryException;
  19 import javax.jcr.Session;
  20 import javax.jcr.nodetype.NodeType;
  21
  22 import org.apache.commons.io.IOUtils;
  23 import org.argeo.jcr.JcrUtils;
  24
  25 public class BinaryChannel implements SeekableByteChannel {
  26         private final Node file;
  27         private Binary binary;
  28         private boolean open = true;
  29
  30         private long position = 0;
  31
  32         // private ByteBuffer toWrite;
  33         private FileChannel fc = null;
  34
  35         public BinaryChannel(Node file) throws RepositoryException, IOException {
  36                 this.file = file;
  37                 // int capacity = 1024 * 1024;
  38                 // this.toWrite = ByteBuffer.allocate(capacity);
  39                 if (file.isNodeType(NodeType.NT_FILE)) {
  40                         if (file.hasNode(Property.JCR_CONTENT)) {
  41                                 Node data = file.getNode(Property.JCR_CONTENT);
  42                                 this.binary = data.getProperty(Property.JCR_DATA).getBinary();
  43                         } else {
  44                                 Node data = file.addNode(Property.JCR_CONTENT, NodeType.NT_RESOURCE);
  45                                 try (InputStream in = new ByteArrayInputStream(new byte[0])) {
  46                                         this.binary = data.getSession().getValueFactory().createBinary(in);
  47                                 }
  48                                 data.setProperty(Property.JCR_DATA, this.binary);
  49                                 data.getSession().save();
  50                         }
  51                 } else {
  52                         throw new IllegalArgumentException(
  53                                         "Unsupported file node " + file + " (" + file.getPrimaryNodeType() + ")");
  54                 }
  55         }
  56
  57         @Override
  58         public synchronized boolean isOpen() {
  59                 return open;
  60         }
  61
  62         @Override
  63         public synchronized void close() throws IOException {
  64                 if (isModified()) {
  65                         Binary newBinary = null;
  66                         try {
  67                                 Session session = file.getSession();
  68                                 // byte[] arr = new byte[(int) position];
  69                                 // toWrite.flip();
  70                                 // toWrite.get(arr);
  71                                 fc.position(0);
  72                                 InputStream in = Channels.newInputStream(fc);
  73                                 newBinary = session.getValueFactory().createBinary(in);
  74                                 file.getNode(Property.JCR_CONTENT).setProperty(Property.JCR_DATA, newBinary);
  75                                 session.save();
  76                                 open = false;
  77                         } catch (RepositoryException e) {
  78                                 throw new JcrFsException("Cannot close " + file, e);
  79                         } finally {
  80                                 JcrUtils.closeQuietly(newBinary);
  81                                 IOUtils.closeQuietly(fc);
  82                         }
  83                 } else {
  84                         clearReadState();
  85                         open = false;
  86                 }
  87         }
  88
  89         @Override
  90         public int read(ByteBuffer dst) throws IOException {
  91                 if (isModified()) {
  92                         return fc.read(dst);
  93                 } else {
  94
  95                         try {
  96                                 int read;
  97                                 // int capacity = dst.capacity();
  98                                 byte[] arr = dst.array();
  99                                 read = binary.read(arr, position);
 100                                 // dst.put(arr, 0, read);
 101
 102                                 // try {
 103                                 // byte[] arr = dst.array();
 104                                 // read = binary.read(arr, position);
 105                                 // } catch (UnsupportedOperationException e) {
 106                                 // int capacity = dst.capacity();
 107                                 // byte[] arr = new byte[capacity];
 108                                 // read = binary.read(arr, position);
 109                                 // dst.put(arr);
 110                                 // }
 111                                 if (read != -1)
 112                                         position = position + read;
 113                                 return read;
 114                         } catch (RepositoryException e) {
 115                                 throw new JcrFsException("Cannot read into buffer", e);
 116                         }
 117                 }
 118         }
 119
 120         @Override
 121         public int write(ByteBuffer src) throws IOException {
 122                 int written = getFileChannel().write(src);
 123                 return written;
 124                 // int byteCount = src.remaining();
 125                 // if (toWrite.remaining() < byteCount)
 126                 // throw new JcrFsException("Write buffer is full");
 127                 // toWrite.put(src);
 128                 // if (position < binarySize)
 129                 // position = binarySize + byteCount;
 130                 // else
 131                 // position = position + byteCount;
 132                 // return byteCount;
 133         }
 134
 135         @Override
 136         public long position() throws IOException {
 137                 if (isModified())
 138                         return getFileChannel().position();
 139                 else
 140                         return position;
 141         }
 142
 143         @Override
 144         public SeekableByteChannel position(long newPosition) throws IOException {
 145                 if (isModified()) {
 146                         getFileChannel().position(position);
 147                 } else {
 148                         this.position = newPosition;
 149                 }
 150                 return this;
 151         }
 152
 153         @Override
 154         public long size() throws IOException {
 155                 if (isModified()) {
 156                         return getFileChannel().size();
 157                 } else {
 158                         try {
 159                                 return binary.getSize();
 160                         } catch (RepositoryException e) {
 161                                 throw new JcrFsException("Cannot get size", e);
 162                         }
 163                 }
 164         }
 165
 166         @Override
 167         public SeekableByteChannel truncate(long size) throws IOException {
 168                 getFileChannel().truncate(size);
 169                 // if (size != size())
 170                 // throw new UnsupportedOperationException("Cannot truncate JCR
 171                 // binary");
 172                 return this;
 173         }
 174
 175         private FileChannel getFileChannel() throws IOException {
 176                 try {
 177                         if (fc == null) {
 178                                 Path tempPath = Files.createTempFile(getClass().getSimpleName(), null);
 179                                 fc = FileChannel.open(tempPath, StandardOpenOption.WRITE, StandardOpenOption.READ,
 180                                                 StandardOpenOption.DELETE_ON_CLOSE, StandardOpenOption.SPARSE);
 181                                 ReadableByteChannel readChannel = Channels.newChannel(binary.getStream());
 182                                 fc.transferFrom(readChannel, 0, binary.getSize());
 183                                 clearReadState();
 184                         }
 185                         return fc;
 186                 } catch (RepositoryException e) {
 187                         throw new JcrFsException("Cannot get temp file channel", e);
 188                 }
 189         }
 190
 191         private boolean isModified() {
 192                 return fc != null;
 193         }
 194
 195         private void clearReadState() {
 196                 position = -1;
 197                 JcrUtils.closeQuietly(binary);
 198                 binary = null;
 199         }
 200 }