将Java InputStream的内容写入OutputStream的简便方法

import java.io.InputStream;
import java.io.OutputStream;
import java.nio.channels.Channels;
import java.nio.channels.WritableByteChannel;

public class InputStreamToOutputStream {
    public static void copy(InputStream input, OutputStream output) {
        WritableByteChannel outChannel = Channels.newChannel(output);
        try {
            byte[] buffer = new byte[4096];
            int bytesRead;
            while ((bytesRead = input.read(buffer)) != -1) {
                outChannel.write(ByteBuffer.wrap(buffer, 0, bytesRead));
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                outChannel.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

InputStream input = new FileInputStream("input.txt");
OutputStream output = new FileOutputStream("output.txt");
InputStreamToOutputStream.copy(input, output);