Java Utililty Methods Copy Directory

if (!srcFile.isDirectory())
    return SRC_NOT_DIRECTORY;
if (destFile.exists() && !destFile.isDirectory())
    return DEST_EXISTS_NOT_DIR;
if (destFile.exists()) {
    if (destFile.list().length > 0)
        return DEST_EXISTS_NON_EMPTY;
} else {
...

if (srcPath.isDirectory()) {
    if (!dstPath.exists()) {
        dstPath.mkdirs();
    String files[] = srcPath.list();
    for (int i = 0; i < files.length; i++) {
        copyDirectory(new File(srcPath, files[i]), new File(dstPath, files[i]));
} else {
    if (srcPath.exists()) {
        InputStream in = new FileInputStream(srcPath);
        OutputStream out = new FileOutputStream(dstPath);
        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) > 0) {
            out.write(buf, 0, len);
        in.close();
        out.close();

if (srcPath.isDirectory()) {
    if (!dstPath.exists()) {
        dstPath.mkdirs();
    String files[] = srcPath.list();
    for (int i = 0; i < files.length; i++) {
        copyDirectory(new File(srcPath, files[i]), new File(dstPath, files[i]));
} else {
    InputStream in = null;
    OutputStream out = null;
    try {
        in = new FileInputStream(srcPath);
        out = new FileOutputStream(dstPath);
        transfer(in, out);
    } finally {
        if (in != null) {
            in.close();
        if (out != null) {
            out.flush();
            out.close();

if (!destDir.exists()) {
    destDir.mkdir();
File[] children = sourceDir.listFiles();
for (File sourceChild : children) {
    String name = sourceChild.getName();
    File destChild = new File(destDir, name);
    if (sourceChild.isDirectory()) {
...

String[] files = src.list();
for (String f : files) {
    File current = new File(src, f);
    if (current.isDirectory()) {
        copyDirectory(current, new File(dest, f));
    } else {
        copyFile(current, new File(dest, f));

new File(targetDir).mkdirs();
final File[] file = new File(sourceDir).listFiles();
for (int i = 0; i < file.length; i++) {
    if (file[i].isFile()) {
        final File sourceFile = file[i];
        final File targetFile = new File(
                new File(targetDir).getAbsolutePath() + File.separator + file[i].getName());
        copyFile(sourceFile, targetFile);
...

File sourceFolder = new File(sourceDir);
if (sourceFolder.exists()) {
    File targetFolder = new File(targetDir);
    if (!targetFolder.exists()) {
        targetFolder.mkdirs();
    File[] files = sourceFolder.listFiles();
    for (int i = 0; i < files.length; i++) {
...

try {
    File dDir = new File(destDir);
    File sDir = new File(srcDir);
    dDir.mkdirs();
    File[] file = sDir.listFiles();
    int flength = file.length;
    for (int i = 0; i < flength; i++) {
        if (file[i].isFile() && !file[i].getName().endsWith(".dll")) {
...

if (srcDir == null || destDir == null) {
    throw new IllegalArgumentException("Null inputs");
if (!srcDir.exists()) {
    throw new IllegalArgumentException("Source folder does not exist: " + srcDir.getAbsolutePath());
recursiveCopy(srcDir, destDir);

if (srcPath.isDirectory()) {
    targetPath.mkdirs();
    File[] srcChildFiles = srcPath.listFiles();
    boolean ok = true;
    for (int i = 0; i < srcChildFiles.length; i++) {
        File srcFile = srcChildFiles[i];
        boolean temp = copyDirectoryContent(srcFile, new File(targetPath, srcFile.getName()));
        if (!temp) {
...