Walks a file tree, generating a sequence of events corresponding to the files in the tree.

Path top = ...
Set<FileVisitOption> options = ...
int maxDepth = ...

try (FileTreeWalker walker = new FileTreeWalker(options, maxDepth)) {
    FileTreeWalker.Event ev = walker.walk(top);
    do {
        process(ev);
        ev = walker.next();
    } while (ev != null);
}

Nested and Inner Type Summary

Modifier and Type	Class and Description
private static class	FileTreeWalker.DirectoryNode The element on the walking stack corresponding to a directory node.
pack-priv static class	FileTreeWalker.Event Events returned by the `walk` and `next` methods.
pack-priv static enum	FileTreeWalker.EventType The event types.

Field Summary

Modifier and Type	Field and Description
private boolean	closed
private final boolean	followLinks
private final LinkOption[]	linkOptions
private final int	maxDepth
private final ArrayDeque<FileTreeWalker.DirectoryNode>	stack

Constructor Summary

Access	Constructor and Description
pack-priv	FileTreeWalker(Collection<FileVisitOption> options, int maxDepth) Creates a `FileTreeWalker`.

Method Summary

Modifier and Type	Method and Description
public void	close() Implements java.io.Closeable.close. Closes/pops all directories on the stack.
private BasicFileAttributes	getAttributes(Path file, boolean canUseCached) Returns the attributes of the given file, taking into account whether the walk is following sym links is not.
pack-priv boolean	isOpen() Returns `true` if the walker is open.
pack-priv FileTreeWalker.Event	next() Returns the next Event or `null` if there are no more events or the walker is closed.
pack-priv void	pop() Pops the directory node that is the current top of the stack so that there are no more events for the directory (including no END_DIRECTORY) event.
pack-priv void	skipRemainingSiblings() Skips the remaining entries in the directory at the top of the stack.
private FileTreeWalker.Event	visit(Path entry, boolean canUseCached) Visits the given file, returning the `Event` corresponding to that visit.
pack-priv FileTreeWalker.Event	walk(Path file) Start walking from the given file.
private boolean	wouldLoop(Path dir, Object key) Returns true if walking into the given directory would result in a file system loop/cycle.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

closed	back to summary
private boolean closed

followLinks	back to summary
private final boolean followLinks

linkOptions	back to summary
private final LinkOption[] linkOptions

maxDepth	back to summary
private final int maxDepth

stack	back to summary
private final ArrayDeque<FileTreeWalker.DirectoryNode> stack

Constructor Detail

FileTreeWalker back to summary

FileTreeWalker	back to summary
pack-priv FileTreeWalker(Collection<FileVisitOption> options, int maxDepth) Creates a `FileTreeWalker`. Exceptions IllegalArgumentException: if `maxDepth` is negative ClassCastException: if `options` contains an element that is not a `FileVisitOption` NullPointerException: if `options` is `null` or the options array contains a `null` element

pack-priv FileTreeWalker(Collection<FileVisitOption> options, int maxDepth)

Creates a FileTreeWalker.

Exceptions

IllegalArgumentException:: if maxDepth is negative
ClassCastException:: if options contains an element that is not a FileVisitOption
NullPointerException:: if options is null or the options array contains a null element

Method Detail

close	back to summary
public void close() Implements java.io.Closeable.close. Closes/pops all directories on the stack. Annotations @Override

back to summary

public void close()

Implements java.io.Closeable.close.

Closes/pops all directories on the stack.

Annotations

@Override

getAttributes	back to summary
private BasicFileAttributes getAttributes(Path file, boolean canUseCached) throws IOException Returns the attributes of the given file, taking into account whether the walk is following sym links is not. The `canUseCached` argument determines whether this method can use cached attributes.

isOpen	back to summary
pack-priv boolean isOpen() Returns `true` if the walker is open.

next	back to summary
pack-priv FileTreeWalker.Event next() Returns the next Event or `null` if there are no more events or the walker is closed.

pop	back to summary
pack-priv void pop() Pops the directory node that is the current top of the stack so that there are no more events for the directory (including no END_DIRECTORY) event. This method is a no-op if the stack is empty or the walker is closed.

skipRemainingSiblings	back to summary
pack-priv void skipRemainingSiblings() Skips the remaining entries in the directory at the top of the stack. This method is a no-op if the stack is empty or the walker is closed.

visit	back to summary
private FileTreeWalker.Event visit(Path entry, boolean canUseCached) Visits the given file, returning the `Event` corresponding to that visit. The `canUseCached` parameter determines whether cached attributes for the file can be used or not.

walk	back to summary
pack-priv FileTreeWalker.Event walk(Path file) Start walking from the given file.

wouldLoop	back to summary
private boolean wouldLoop(Path dir, Object key) Returns true if walking into the given directory would result in a file system loop/cycle.

java.nio.file back to summary

private Class FileTreeWalker.DirectoryNode

Class Inheritance

extends Object

java.lang.Object
java.nio.file.FileTreeWalker.DirectoryNode

The element on the walking stack corresponding to a directory node.

Field Summary

Modifier and Type	Field and Description
private final Path	dir
private final Iterator<Path>	iterator
private final Object	key
private boolean	skipped
private final DirectoryStream<Path>	stream

Constructor Summary

Access	Constructor and Description
pack-priv	DirectoryNode(Path dir, Object key, DirectoryStream<Path> stream)

Method Summary

Modifier and Type	Method and Description
pack-priv Path	directory()
pack-priv Iterator<Path>	iterator()
pack-priv Object	key()
pack-priv void	skip()
pack-priv boolean	skipped()
pack-priv DirectoryStream<Path>	stream()

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

dir	back to summary
private final Path dir

iterator	back to summary
private final Iterator<Path> iterator

key	back to summary
private final Object key

skipped	back to summary
private boolean skipped

stream	back to summary
private final DirectoryStream<Path> stream

Constructor Detail

DirectoryNode	back to summary
pack-priv DirectoryNode(Path dir, Object key, DirectoryStream<Path> stream)

Method Detail

directory	back to summary
pack-priv Path directory()

iterator	back to summary
pack-priv Iterator<Path> iterator()

key	back to summary
pack-priv Object key()

skip	back to summary
pack-priv void skip()

skipped	back to summary
pack-priv boolean skipped()

stream	back to summary
pack-priv DirectoryStream<Path> stream()

java.nio.file back to summary

pack-priv Class FileTreeWalker.Event

Class Inheritance

extends Object

java.lang.Object
java.nio.file.FileTreeWalker.Event

Events returned by the walk and next methods.

Field Summary

Modifier and Type	Field and Description
private final BasicFileAttributes	attrs
private final Path	file
private final IOException	ioe
private final FileTreeWalker.EventType	type

Constructor Summary

Access	Constructor and Description
private	Event(FileTreeWalker.EventType type, Path file, BasicFileAttributes attrs, IOException ioe)
pack-priv	Event(FileTreeWalker.EventType type, Path file, BasicFileAttributes attrs)
pack-priv	Event(FileTreeWalker.EventType type, Path file, IOException ioe)

Method Summary

Modifier and Type	Method and Description
pack-priv BasicFileAttributes	attributes()
pack-priv Path	file()
pack-priv IOException	ioeException()
pack-priv FileTreeWalker.EventType	type()

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

attrs	back to summary
private final BasicFileAttributes attrs

file	back to summary
private final Path file

ioe	back to summary
private final IOException ioe

type	back to summary
private final FileTreeWalker.EventType type

Constructor Detail

Event	back to summary
private Event(FileTreeWalker.EventType type, Path file, BasicFileAttributes attrs, IOException ioe)

Event	back to summary
pack-priv Event(FileTreeWalker.EventType type, Path file, BasicFileAttributes attrs)

Event	back to summary
pack-priv Event(FileTreeWalker.EventType type, Path file, IOException ioe)

Method Detail

attributes	back to summary
pack-priv BasicFileAttributes attributes()

file	back to summary
pack-priv Path file()

ioeException	back to summary
pack-priv IOException ioeException()

type	back to summary
pack-priv FileTreeWalker.EventType type()

java.nio.file back to summary

pack-priv final Enum FileTreeWalker.EventType

Class Inheritance

extends Enum<FileTreeWalker.EventType>

java.lang.Object
java.lang.Enum
java.nio.file.FileTreeWalker.EventType

The event types.

Field Summary

Modifier and Type	Field and Description
public static final FileTreeWalker.EventType	END_DIRECTORY End of a directory
public static final FileTreeWalker.EventType	ENTRY An entry in a directory
public static final FileTreeWalker.EventType	START_DIRECTORY Start of a directory

Constructor Summary

Access	Constructor and Description
private	EventType()

Method Summary

Modifier and Type	Method and Description
public static FileTreeWalker.EventType	valueOf(String name)
public static FileTreeWalker.EventType[]	values()

Inherited from java.lang.Enum:: clone compareTo describeConstable equals finalize getDeclaringClass hashCode name ordinal toString valueOf

Field Detail

END_DIRECTORY	back to summary
public static final FileTreeWalker.EventType END_DIRECTORY End of a directory

ENTRY	back to summary
public static final FileTreeWalker.EventType ENTRY An entry in a directory

START_DIRECTORY	back to summary
public static final FileTreeWalker.EventType START_DIRECTORY Start of a directory

Constructor Detail

EventType	back to summary
private EventType()

Method Detail

valueOf	back to summary
public static FileTreeWalker.EventType valueOf(String name)

values	back to summary
public static FileTreeWalker.EventType[] values()