Android Utililty Methods Zip Directory

if (p2BeZippedDir == null) {
    throw new IllegalArgumentException(
            "parameter p2BeZippedDir must not be null");
if (!p2BeZippedDir.isDirectory()) {
    throw new IllegalArgumentException(
            "parameter p2BeZippedDir has to be a directory");
if (pZipFile == null) {
    throw new IllegalArgumentException(
            "parameter pZipFile must not be null");
if (pZipFile.isDirectory()) {
    throw new IllegalArgumentException(
            "parameter pZipFile has to be a file and not a directory");
Vector<File> lFileList = find(p2BeZippedDir, ".+");
String lDirName = p2BeZippedDir.getAbsolutePath();
int lBegin = lDirName.length() + 1;
String lEntryName = null;
try {
    boolean lIsEntryWritten = false;
    pZipFile.delete();
    FileOutputStream lFOS = new FileOutputStream(pZipFile);
    BufferedOutputStream lBOS = new BufferedOutputStream(lFOS);
    ZipOutputStream lZOS = new ZipOutputStream(lBOS);
    for (File lFile : lFileList) {
        if (lFile.isFile()) {
            lIsEntryWritten = true;
            lEntryName = lFile.getAbsolutePath();
            lEntryName = "/" + lEntryName.substring(lBegin);
            lEntryName = lEntryName.replaceAll("\\\\", "/");
            ZipEntry lZipEntry = new ZipEntry(lEntryName);
            lZOS.putNextEntry(lZipEntry);
            FileInputStream lFIS = new FileInputStream(lFile);
            BufferedInputStream lBIS = new BufferedInputStream(lFIS);
            copy(lBIS, lZOS);
            lZOS.closeEntry();
    if (!lIsEntryWritten) {
        lZOS.putNextEntry(new ZipEntry("ZipFileIsEmpty"));
        lZOS.closeEntry();
    lZOS.close();
} catch (ZipException e) {
    throw new RuntimeException("could not zip entry:" + lEntryName,
            e);
} catch (IOException e) {
    throw new RuntimeException(e);

File[] files = directory.listFiles();
byte[] buffer = new byte[8192];
int read = 0;
for (int i = 0, n = files.length; i < n; i++) {
    if (files[i].isDirectory()) {
        zip(files[i], base, zos);
    } else {
        FileInputStream in = new FileInputStream(files[i]);
...

File[] files = directory.listFiles();
byte[] buffer = new byte[8192];
int read = 0;
for (int i = 0, n = files.length; i < n; i++) {
    if (files[i].isDirectory()) {
        zip(files[i], base, zos);
    } else {
        FileInputStream in = new FileInputStream(files[i]);
...

if (zos == null || folder == null) {
    return;
File[] fileList = folder.listFiles();
if (fileList == null || fileList.length == 0) {
    return;
for (File file : fileList) {
...