package ezdb.rocksdb.util;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import com.google.common.io.Files;
import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
//implementation taken from leveldbjni
public class FileUtils
{
private static final int TEMP_DIR_ATTEMPTS = 10000;
public static boolean isSymbolicLink(File file)
{
try {
final File canonicalFile = file.getCanonicalFile();
final File absoluteFile = file.getAbsoluteFile();
final File parentFile = file.getParentFile();
// a symbolic link has a different name between the canonical and absolute path
return !canonicalFile.getName().equals(absoluteFile.getName()) ||
// or the canonical parent path is not the same as the file's parent path,
// provided the file has a parent path
parentFile != null && !parentFile.getCanonicalPath().equals(canonicalFile.getParent());
}
catch (IOException e) {
// error on the side of caution
return true;
}
}
public static ImmutableList<File> listFiles(File dir)
{
File[] files = dir.listFiles();
if (files == null) {
return ImmutableList.of();
}
return ImmutableList.copyOf(files);
}
public static ImmutableList<File> listFiles(File dir, FilenameFilter filter)
{
File[] files = dir.listFiles(filter);
if (files == null) {
return ImmutableList.of();
}
return ImmutableList.copyOf(files);
}
public static File createTempDir(String prefix)
{
return createTempDir(new File(System.getProperty("java.io.tmpdir")), prefix);
}
public static File createTempDir(File parentDir, String prefix)
{
String baseName = "";
if (prefix != null) {
baseName += prefix + "-";
}
baseName += System.currentTimeMillis() + "-";
for (int counter = 0; counter < TEMP_DIR_ATTEMPTS; counter++) {
File tempDir = new File(parentDir, baseName + counter);
if (tempDir.mkdir()) {
return tempDir;
}
}
throw new IllegalStateException("Failed to create directory within "
+ TEMP_DIR_ATTEMPTS + " attempts (tried "
+ baseName + "0 to " + baseName + (TEMP_DIR_ATTEMPTS - 1) + ')');
}
public static boolean deleteDirectoryContents(File directory)
{
Preconditions.checkArgument(directory.isDirectory(), "Not a directory: %s", directory);
// Don't delete symbolic link directories
if (isSymbolicLink(directory)) {
return false;
}
boolean success = true;
for (File file : listFiles(directory)) {
success = deleteRecursively(file) && success;
}
return success;
}
public static boolean deleteRecursively(File file)
{
boolean success = true;
if (file.isDirectory()) {
success = deleteDirectoryContents(file);
}
return file.delete() && success;
}
public static boolean copyDirectoryContents(File src, File target)
{
Preconditions.checkArgument(src.isDirectory(), "Source dir is not a directory: %s", src);
// Don't delete symbolic link directories
if (isSymbolicLink(src)) {
return false;
}
target.mkdirs();
Preconditions.checkArgument(target.isDirectory(), "Target dir is not a directory: %s", src);
boolean success = true;
for (File file : listFiles(src)) {
success = copyRecursively(file, new File(target, file.getName())) && success;
}
return success;
}
public static boolean copyRecursively(File src, File target)
{
if (src.isDirectory()) {
return copyDirectoryContents(src, target);
}
else {
try {
Files.copy(src, target);
return true;
}
catch (IOException e) {
return false;
}
}
}
public static File newFile(String parent, String... paths)
{
Preconditions.checkNotNull(parent, "parent is null");
Preconditions.checkNotNull(paths, "paths is null");
return newFile(new File(parent), ImmutableList.copyOf(paths));
}
public static File newFile(File parent, String... paths)
{
Preconditions.checkNotNull(parent, "parent is null");
Preconditions.checkNotNull(paths, "paths is null");
return newFile(parent, ImmutableList.copyOf(paths));
}
public static File newFile(File parent, Iterable<String> paths)
{
Preconditions.checkNotNull(parent, "parent is null");
Preconditions.checkNotNull(paths, "paths is null");
File result = parent;
for (String path : paths) {
result = new File(result, path);
}
return result;
}
}