/*
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* Portions of this software were developed by the Unidata Program at the
* University Corporation for Atmospheric Research.
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package thredds.filesystem;
import net.jcip.annotations.ThreadSafe;
import thredds.inventory.CollectionConfig;
import thredds.inventory.*;
import java.util.*;
import java.io.File;
/**
* Implements an MController without caching, reading from OS each time.
* recheck is ignored (always true)
*
* @author caron
* @since Jun 25, 2009
*/
@ThreadSafe
public class ControllerOS implements MController {
static private org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(ControllerOS.class);
////////////////////////////////////////
public ControllerOS() {
}
@Override
public Iterator<MFile> getInventoryAll(CollectionConfig mc, boolean recheck) {
String path = mc.getDirectoryName();
if (path.startsWith("file:")) {
path = path.substring(5);
}
File cd = new File(path);
if (!cd.exists()) return null;
if (!cd.isDirectory()) return null;
return new FilteredIterator(mc, new MFileIteratorAll(cd), false);
}
@Override
public Iterator<MFile> getInventoryTop(CollectionConfig mc, boolean recheck) {
String path = mc.getDirectoryName();
if (path.startsWith("file:")) {
path = path.substring(5);
}
File cd = new File(path);
if (!cd.exists()) return null;
if (!cd.isDirectory()) return null;
return new FilteredIterator(mc, new MFileIterator(cd), false); // removes subdirs
}
public Iterator<MFile> getSubdirs(CollectionConfig mc, boolean recheck) {
String path = mc.getDirectoryName();
if (path.startsWith("file:")) {
path = path.substring(5);
}
File cd = new File(path);
if (!cd.exists()) return null;
if (!cd.isDirectory()) return null;
return new FilteredIterator(mc, new MFileIterator(cd), true); // return only subdirs
}
public void close() {
} // NOOP
////////////////////////////////////////////////////////////
// handles filtering and removing/including subdirectories
private static class FilteredIterator implements Iterator<MFile> {
private Iterator<MFile> orgIter;
private CollectionConfig mc;
private boolean wantDirs;
private MFile next;
FilteredIterator(CollectionConfig mc, Iterator<MFile> iter, boolean wantDirs) {
this.orgIter = iter;
this.mc = mc;
this.wantDirs = wantDirs;
}
public boolean hasNext() {
next = nextFilteredFile(); /// 7
return (next != null);
}
public MFile next() {
if (next == null) throw new NoSuchElementException();
return next;
}
public void remove() {
throw new UnsupportedOperationException();
}
private MFile nextFilteredFile() {
if (orgIter == null) return null;
if (!orgIter.hasNext()) return null;
MFile pdata = orgIter.next();
while ((pdata.isDirectory() != wantDirs) || !mc.accept(pdata)) { // skip directories, and filter
if (!orgIter.hasNext()) return null; /// 6
pdata = orgIter.next();
}
return pdata;
}
}
// returns everything in the current directory
private static class MFileIterator implements Iterator<MFile> {
List<File> files;
int count = 0;
MFileIterator(File dir) {
File[] f = dir.listFiles();
if (f == null) { // null on i/o error
logger.warn("I/O error on " + dir.getPath());
throw new IllegalStateException("dir.getPath() returned null on " + dir.getPath());
} else
files = Arrays.asList(f);
}
MFileIterator(List<File> files) {
this.files = files;
}
public boolean hasNext() {
return count < files.size();
}
public MFile next() {
File cfile = files.get(count++);
return new MFileOS(cfile);
}
public void remove() {
throw new UnsupportedOperationException();
}
}
// recursively scans everything in the directory and in subdirectories, depth first (leaves before subdirs)
private static class MFileIteratorAll implements Iterator<MFile> {
Queue<Traversal> traverse;
Traversal currTraversal;
Iterator<MFile> currIter;
MFileIteratorAll(File top) {
traverse = new LinkedList<>();
currTraversal = new Traversal(top);
}
public boolean hasNext() {
if (currIter == null) {
currIter = getNextIterator();
if (currIter == null) {
return false;
}
}
if (!currIter.hasNext()) {
currIter = getNextIterator(); /// 5
return hasNext();
}
return true;
}
public MFile next() {
return currIter.next();
}
private Iterator<MFile> getNextIterator() {
if (!currTraversal.leavesAreDone) {
currTraversal.leavesAreDone = true;
return new MFileIterator(currTraversal.fileList); // look for leaves in the current directory. may be empty.
} else {
if ((currTraversal.subdirIterator != null) && currTraversal.subdirIterator.hasNext()) { // has subdirs
File nextDir = currTraversal.subdirIterator.next(); /// NCDC gets null
traverse.add(currTraversal); // keep track of current traversal
currTraversal = new Traversal(nextDir); /// 2
return getNextIterator();
} else {
if (traverse.peek() == null) return null;
currTraversal = traverse.remove();
return getNextIterator(); // 3 and 4 iteration
}
}
}
public void remove() {
throw new UnsupportedOperationException();
}
}
// traversal of one directory
private static class Traversal {
List<File> fileList; // list of files
Iterator<File> subdirIterator; // list of subdirs
boolean leavesAreDone = false; // when all the files are done, start on the subdirs
Traversal(File dir) {
fileList = new ArrayList<>();
if (dir == null) return; // LOOK WHY
if (dir.listFiles() == null) return;
if (logger.isTraceEnabled()) logger.trace("List Directory "+dir);
List<File> subdirList = new ArrayList<>();
File[] files = dir.listFiles();
if (files != null)
for (File f : files) { /// 1
if (f == null) {
logger.warn(" NULL FILE in directory "+dir);
continue;
}
if (logger.isTraceEnabled()) logger.trace(" File "+f);
if (f.isDirectory())
subdirList.add(f);
else
fileList.add(f);
}
if (subdirList.size() > 0)
this.subdirIterator = subdirList.iterator();
}
}
}