bundles/org.simantics.graph/src/org/simantics/graph/representation/InputChannel.java

   1 package org.simantics.graph.representation;
   2
   3 import java.io.IOException;
   4 import java.io.InputStream;
   5 import java.nio.ByteBuffer;
   6 import java.nio.channels.ReadableByteChannel;
   7
   8 public class InputChannel implements ReadableByteChannel {
   9
  10         private final InputStream stream;
  11
  12         public InputChannel(InputStream stream) {
  13                 this.stream = stream;
  14         }
  15
  16         @Override
  17         public boolean isOpen() {
  18                 return true;
  19         }
  20
  21         @Override
  22         public void close() throws IOException {
  23                 // NOTE: it is an intentional choice not to close the underlying stream here
  24                 // InputStreams given directly to TransferableGraphFileReader are expected to
  25                 // be closed outside of this implementation.
  26         }
  27
  28         @Override
  29         public int read(ByteBuffer dst) throws IOException {
  30                 int nRead;
  31                 int size = 0;
  32                 int position = dst.position();
  33                 int limit = dst.limit();
  34                 // The users of this channel expect that the data is fully read at this point
  35                 while ((nRead = stream.read(dst.array(), position, limit - position)) != -1 && limit - position > 0) {
  36                         size += nRead;
  37                         position += nRead;
  38                 }
  39                 return size;
  40         }
  41
  42 }