package net.tomp2p.storage;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.io.Serializable;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
import java.security.InvalidKeyException;
import java.security.SignatureException;
import net.tomp2p.connection.SignatureFactory;
import net.tomp2p.peers.Number160;
import org.mapdb.Serializer;
public class DataSerializer implements Serializer<Data>, Serializable {
private static final long serialVersionUID = 1428836065493792295L;
//TODO: test the performance impact
private static final int MAX_SIZE = 10 * 1024;
final private File path;
final private SignatureFactory signatureFactory;
public DataSerializer(File path, SignatureFactory signatureFactory) {
this.path = path;
this.signatureFactory = signatureFactory;
}
@Override
public void serialize(DataOutput out, Data value) throws IOException {
if (value.length() > MAX_SIZE) {
// header, 1 means stored on disk in a file
out.writeByte(1);
serializeFile(out, value);
} else {
// header, 0 means stored on disk with MapDB
out.writeByte(0);
serializeMapDB(out, value);
}
}
private void serializeMapDB(DataOutput out, Data value) throws IOException {
AlternativeCompositeByteBuf acb = AlternativeCompositeByteBuf.compBuffer();
// store data to disk
// header first
value.encodeHeader(acb, signatureFactory);
write(out, acb.nioBuffers());
acb.skipBytes(acb.writerIndex());
// next data - no need to copy to another buffer, just take the data
// from memory
write(out, value.toByteBuffers());
// rest
try {
value.encodeDone(acb, signatureFactory);
write(out, acb.nioBuffers());
} catch (InvalidKeyException e) {
throw new IOException(e);
} catch (SignatureException e) {
throw new IOException(e);
}
}
private void serializeFile(DataOutput out, Data value) throws IOException, FileNotFoundException {
Number160 hash = value.hash();
// store file name
out.write(hash.toByteArray());
// store as external file, create path
RandomAccessFile file = null;
FileChannel rwChannel = null;
try {
file = new RandomAccessFile(new File(path, hash.toString()), "rw");
rwChannel = file.getChannel();
AlternativeCompositeByteBuf acb = AlternativeCompositeByteBuf.compBuffer();
// store data to disk
// header first
value.encodeHeader(acb, signatureFactory);
rwChannel.write(acb.nioBuffers());
// next data - no need to copy to another buffer, just take the
// data from memory
rwChannel.write(value.toByteBuffers());
// rest
try {
value.encodeDone(acb, signatureFactory);
rwChannel.write(acb.nioBuffers());
} catch (InvalidKeyException e) {
throw new IOException(e);
} catch (SignatureException e) {
throw new IOException(e);
}
} finally {
if (rwChannel != null) {
rwChannel.close();
}
if (file != null) {
file.close();
}
}
}
private void write(DataOutput out, ByteBuffer[] nioBuffers) throws IOException {
final int length = nioBuffers.length;
for(int i=0;i < length; i++) {
int remaining = nioBuffers[i].remaining();
if(nioBuffers[i].hasArray()) {
out.write(nioBuffers[i].array(), nioBuffers[i].arrayOffset(), remaining);
} else {
byte[] me = new byte[remaining];
nioBuffers[i].get(me);
out.write(me);
}
}
}
@Override
public Data deserialize(DataInput in, int available) throws IOException {
int header = in.readByte();
if(header == 1) {
return deserializeFile(in);
} else if(header == 0) {
return deserializeMapDB(in);
} else {
throw new IOException("unexpected header: " + header);
}
}
private Data deserializeMapDB(DataInput in) throws IOException {
ByteBuf buf = Unpooled.buffer();
Data data = null;
while(data == null) {
buf.writeByte(in.readByte());
data = Data.decodeHeader(buf, signatureFactory);
}
int len = data.length();
byte me[] = new byte[len];
in.readFully(me);
buf = Unpooled.wrappedBuffer(me);
boolean retVal = data.decodeBuffer(buf);
if(!retVal) {
throw new IOException("data could not be read");
}
retVal = data.decodeDone(buf, signatureFactory);
if(!retVal) {
throw new IOException("signature could not be read");
}
return data;
}
private Data deserializeFile(DataInput in) throws IOException, FileNotFoundException {
byte[] me = new byte[Number160.BYTE_ARRAY_SIZE];
in.readFully(me);
Number160 hash = new Number160(me);
RandomAccessFile file = new RandomAccessFile(new File(path, hash.toString()), "r");
FileChannel inChannel = file.getChannel();
MappedByteBuffer buffer = inChannel.map(FileChannel.MapMode.READ_ONLY, 0, inChannel.size());
buffer.load();
ByteBuf buf = Unpooled.wrappedBuffer(buffer);
Data data = Data.decodeHeader(buf, signatureFactory);
data.decodeBuffer(buf);
data.decodeDone(buf, signatureFactory);
file.close();
return data;
}
@Override
public int fixedSize() {
return -1;
}
}