Java Utililty Methods File Copy nio

FileInputStream in = new FileInputStream(source);
FileOutputStream out = new FileOutputStream(destination);
byte[] buffer = new byte[1024 * 16];
int len;
try {
    while ((len = in.read(buffer)) != -1)
        out.write(buffer, 0, len);
} finally {
...

try {
    FileChannel sourceChannel = new FileInputStream(source.getPath()).getChannel();
    FileChannel destinationChannel = new FileOutputStream(destination.getPath()).getChannel();
    destinationChannel.transferFrom(sourceChannel, 0, sourceChannel.size());
    sourceChannel.close();
    destinationChannel.close();
} catch (Exception e) {
    System.err.println("Couldn't close sources or write");
...

Copys a file

FileChannel inChannel = new FileInputStream(source).getChannel();
FileChannel outChannel = new FileOutputStream(destination).getChannel();
inChannel.transferTo(0, inChannel.size(), outChannel);

if (source.isDirectory()) {
    copyDirectory(source, destination);
} else {
    copyFile(source, destination);

logger.entering("de.axelwernicke.mypod.util.FileUtils", "copy");
long bytesCopied = -1;
try {
    boolean copied = false;
    int tries = 0;
    FileChannel fic = new FileInputStream(source).getChannel();
    FileChannel foc = new FileOutputStream(destination).getChannel();
    do {
...

FileChannel input = null;
FileChannel output = null;
try {
    input = new FileInputStream(source).getChannel();
    output = new FileOutputStream(target).getChannel();
    MappedByteBuffer buffer = input.map(FileChannel.MapMode.READ_ONLY, 0, input.size());
    output.write(buffer);
} finally {
...

FileInputStream sourceOutStream = new FileInputStream(source);
FileOutputStream targetOutStream = new FileOutputStream(target);
FileChannel sourceChannel = sourceOutStream.getChannel();
FileChannel targetChannel = targetOutStream.getChannel();
sourceChannel.transferTo(0, sourceChannel.size(), targetChannel);
sourceChannel.close();
targetChannel.close();
sourceOutStream.close();
...

try (PrintWriter stream = new PrintWriter(new FileWriter(source, true))) {
    Files.lines(target.toPath()).forEach(s -> {
        stream.println(s);
    });

copy(source, target, filter, false, true);

if (!destFile.exists()) {
    destFile.createNewFile();
FileChannel source = null;
FileChannel destination = null;
try {
    source = new FileInputStream(sourceFile).getChannel();
    destination = new FileOutputStream(destFile).getChannel();
...