BlockTransferService.java

package com.github.ruediste1.btrbck;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;

import javax.inject.Singleton;

import com.github.ruediste1.btrbck.dto.Block;
import com.google.common.io.ByteStreams;

@Singleton
public class BlockTransferService {

    /**
     * Read blocks from the input and send the data to the output
     */
    public void readBlocks(InputStream input, OutputStream output)
            throws IOException, ClassNotFoundException {
        boolean isFirst = true;
        while (true) {

            Block block = Util.read(Block.class, input);
            if (!isFirst && block.isFirst) {
                throw new RuntimeException("Unexpected block marked as first");
            }
            ByteStreams.copy(new ByteArrayInputStream(block.data), output);
            if (block.isLast) {
                break;
            }
        }
    }

    /**
     * Read data from the input and send it as blocks to the output
     */
    public void sendBlocks(InputStream input, OutputStream output, int blocksize)
            throws IOException {

        Block block = new Block();
        block.isFirst = true;
        block.isLast = false;
        byte[] buf = new byte[blocksize];

        while (true) {
            int result = input.read(buf);
            if (result < 0) {
                break;
            }
            block.data = Arrays.copyOf(buf, result);
            Util.send(block, output);
            block.isFirst = false;
        }
        block.isLast = true;
        block.data = new byte[] {};
        Util.send(block, output);
        // out.writeObject(block);
        // out.reset();
        // out.flush();
    }
}