//package com.myapp.util.file;
import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.net.URI;
import java.net.URL;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
public class FileUtils {
public Collection<File> lookupClasspathFiles(String name) {
Enumeration<URL> resources;
List<File> files = new ArrayList<File>();
try {
resources = FileUtils.class.getClassLoader().getResources(name);
while (resources.hasMoreElements()) {
URI uri = resources.nextElement().toURI();
File file = new File(uri);
files.add(file);
}
} catch (Exception e) {
throw new RuntimeException("could not lookup files with name: "+name, e);
}
return files;
}
public static class FileFileFilter implements FileFilter {
@Override
public boolean accept(File pathname) {
return pathname.isFile();
}
}
public static class DirectoryFileFilter implements FileFilter {
@Override
public boolean accept(File pathname) {
return pathname.isDirectory();
}
}
public static final class RecursiveFileIterator implements Iterator<File> {
private final List<File> recursiveListing;
private final int size;
private int nextIndex = -1;
public RecursiveFileIterator(File root,
boolean includeDirs,
boolean includeFiles) {
List<File> l = new ArrayList<File>();
traverse(root, includeDirs, includeFiles, l);
recursiveListing = Collections.unmodifiableList(l);
size = recursiveListing.size();
if (size > 0) {
nextIndex = 0;
}
}
private List<File> traverse(File startDir,
final boolean includeDirs,
final boolean includeFiles,
List<File> toAdd) {
validateDirectory(startDir);
File[] filesAndDirs = startDir.listFiles();
Arrays.sort(filesAndDirs);
File tmp = null;
boolean isDir, isFile;
for (int i = 0; i < filesAndDirs.length; i++) {
tmp = filesAndDirs[i];
isDir = tmp.isDirectory();
isFile = tmp.isFile();
if (isDir) {
if (includeDirs)
toAdd.add(tmp);
traverse(tmp, includeDirs, includeFiles, toAdd);
} else if (isFile) {
if (includeFiles)
toAdd.add(tmp);
}
}
return toAdd;
}
@Override
public File next() {
File next = recursiveListing.get(nextIndex);
nextIndex++;
return next;
}
@Override
public boolean hasNext() {
if (size < 0) {
return false; // empty list
}
if (nextIndex >= size) {
return false; // last element reached
}
return true;
}
@Override
public void remove() {
throw new RuntimeException("not supported yet");
}
/**
* Directory is valid if it exists, does not represent a file, and can
* be read.
*/
private static void validateDirectory(File d) {
if (d == null) {
throw new IllegalArgumentException("Directory should not be null.");
}
if (!d.exists()) {
throw new IllegalArgumentException("Directory does not exist: "
+ d);
}
if (!d.isDirectory()) {
throw new IllegalArgumentException("Is not a directory: " + d);
}
if (!d.canRead()) {
throw new IllegalArgumentException("Directory cannot be read: "
+ d);
}
}
}
private FileUtils() {
}
public static void deleteRecursively(File f) {
if (!f.exists()) {
return;
}
if (f.isDirectory()) {
File[] children = f.listFiles();
if (children != null) {
for (int i = 0; i < children.length; i++) {
deleteRecursively(children[i]);
}
}
}
f.delete();
}
}
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