com.helger.commons.io.file.iterate

Class FileSystemRecursiveIterator

java.lang.Object

com.helger.commons.io.file.iterate.FileSystemRecursiveIterator

All Implemented Interfaces:

IIterableIterator<File>, Iterable<File>, Iterator<File>

@NotThreadSafe
public class FileSystemRecursiveIterator
extends Object
implements IIterableIterator<File>

Recursively iterate the content of a file system directory. This is a depth first iteration, because as soon as a directory is encountered, the children of this directory are iterated.
Note: the order of iteration is undefined and depends on the order returned by FileHelper.getDirectoryContent(File).

Author:

Philip Helger

Constructor Summary

Constructors

Constructor and Description
FileSystemRecursiveIterator(File aBaseDir) Constructor for recursively iterating a file system directory.
FileSystemRecursiveIterator(File aBaseDir, IFileFilter aRecursionFilter) Constructor for recursively iterating a file system directory.
FileSystemRecursiveIterator(String sBaseDir) Constructor for recursively iterating a file system directory.
FileSystemRecursiveIterator(String sBaseDir, IFileFilter aRecursionFilter) Constructor for recursively iterating a file system directory.

Method Summary

Modifier and Type	Method and Description
static IIterableIterator<File>	create(File fBaseDir, IFileFilter... aFileFilters) Create a new iterator that recursively descends into sub-directories starting from the given base directory.
static IIterableIterator<File>	create(File fBaseDir, IFileFilter aFileFilter) Create a new iterator that recursively descends into sub-directories starting from the given base directory.
static IIterableIterator<File>	create(String sBaseDir, IFileFilter... aFileFilters) Create a new iterator that recursively descends into sub-directories starting from the given base directory.
static IIterableIterator<File>	create(String sBaseDir, IFileFilter aFileFilter) Create a new iterator that recursively descends into sub-directories starting from the given base directory.
int	getLevel()
IFileFilter	getRecursionFilter()
int	getStartLevel()
boolean	hasNext()
Iterator<File>	iterator()
File	next()
protected boolean	recurseIntoDirectory(File aDirectory) Override this method to manually filter the directories, which are recursed into.
void	remove()
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface java.util.Iterator

forEachRemaining

Constructor Detail

FileSystemRecursiveIterator

public FileSystemRecursiveIterator(@Nonnull
                                   String sBaseDir)

Constructor for recursively iterating a file system directory.

Parameters:

sBaseDir - The base directory to start with. May not be null.

FileSystemRecursiveIterator

public FileSystemRecursiveIterator(@Nonnull
                                   File aBaseDir)

Constructor for recursively iterating a file system directory.

Parameters:

aBaseDir - The base directory to start with. May not be null.

FileSystemRecursiveIterator

public FileSystemRecursiveIterator(@Nonnull
                                   String sBaseDir,
                                   @Nullable
                                   IFileFilter aRecursionFilter)

Constructor for recursively iterating a file system directory.

Parameters:

sBaseDir - The base directory to start with. May not be null.

aRecursionFilter - An optional filter that controls, into which sub-directories this iterator should descend to. May be null.

FileSystemRecursiveIterator

public FileSystemRecursiveIterator(@Nonnull
                                   File aBaseDir,
                                   @Nullable
                                   IFileFilter aRecursionFilter)

Constructor for recursively iterating a file system directory.

Parameters:

aBaseDir - The base directory to start with. May not be null.

aRecursionFilter - An optional filter that controls, into which sub-directories this iterator should descend to. May be null.

Method Detail

getStartLevel

@Nonnegative
public int getStartLevel()

getRecursionFilter

@Nullable
public IFileFilter getRecursionFilter()

iterator

@Nonnull
public final Iterator<File> iterator()

Specified by:

iterator in interface Iterable<File>

hasNext

public final boolean hasNext()

Specified by:

hasNext in interface Iterator<File>

recurseIntoDirectory

@OverrideOnDemand
protected boolean recurseIntoDirectory(@Nonnull
                                                          File aDirectory)

Override this method to manually filter the directories, which are recursed into.

Parameters:

aDirectory - The non-null directory

Returns:

true if all children of this directory should be investigated

next

@Nonnull
public final File next()

Description copied from interface: IIterableIterator

Specified by:

next in interface IIterableIterator<File>

Specified by:

next in interface Iterator<File>

Returns:

The next element. No constraint whether the element can be null or non-null.

getLevel

@Nonnegative
public final int getLevel()

Returns:

The nesting level of the last file retrieved by next(). Always ≥ 0. The starting directory has level 0.

remove

@UnsupportedOperation
public final void remove()

Specified by:

remove in interface Iterator<File>

toString

public String toString()

Overrides:

toString in class Object

create

@Nonnull
public static IIterableIterator<File> create(@Nonnull
                                                       String sBaseDir,
                                                       @Nonnull
                                                       IFileFilter aFileFilter)

Create a new iterator that recursively descends into sub-directories starting from the given base directory. Additionally a FilenameFilter can be added, that determines, which results to be returned and which not. The difference between the filter passed here and the filter that can be specified in the constructor is the following: the IFilter in the constructor defines into which sub-directories to descend. The FilenameFilter passed to this method only defines which elements should be returned and which not, independent of the iterated files (like a "view").

Parameters:

sBaseDir - The base directory to start iterating. May not be null.

aFileFilter - The file filter to be used. May not be null.

Returns:

Never null.

create

@Nonnull
public static IIterableIterator<File> create(@Nonnull
                                                       File fBaseDir,
                                                       @Nonnull
                                                       IFileFilter aFileFilter)

Create a new iterator that recursively descends into sub-directories starting from the given base directory. Additionally a FilenameFilter can be added, that determines, which results to be returned and which not. The difference between the filter passed here and the filter that can be specified in the constructor is the following: the IFilter in the constructor defines into which sub-directories to descend. The FilenameFilter passed to this method only defines which elements should be returned and which not, independent of the iterated files (like a "view").

Parameters:

fBaseDir - The base directory to start iterating. May not be null.

aFileFilter - The file filter to be used. May not be null.

Returns:

Never null.

create

@Nonnull
public static IIterableIterator<File> create(@Nonnull
                                                       String sBaseDir,
                                                       @Nonnull @Nonempty
                                                       IFileFilter... aFileFilters)

Create a new iterator that recursively descends into sub-directories starting from the given base directory. Additionally a list of FilenameFilters can be added, that determine, which results to be returned and which not. The difference between the filter passed here and the filter that can be specified in the constructor is the following: the IFilter in the constructor defines into which sub-directories to descend. The FilenameFilters passed to this method only define which elements should be returned and which not, independent of the iterated files (like a "view").

Parameters:

sBaseDir - The base directory to start iterating. May not be null.

aFileFilters - The file filter to be used. May neither be null nor empty.

Returns:

Never null.

create

@Nonnull
public static IIterableIterator<File> create(@Nonnull
                                                       File fBaseDir,
                                                       @Nonnull @Nonempty
                                                       IFileFilter... aFileFilters)

Create a new iterator that recursively descends into sub-directories starting from the given base directory. Additionally a list of FilenameFilters can be added, that determine, which results to be returned and which not. The difference between the filter passed here and the filter that can be specified in the constructor is the following: the IFilter in the constructor defines into which sub-directories to descend. The FilenameFilters passed to this method only define which elements should be returned and which not, independent of the iterated files (like a "view").

Parameters:

fBaseDir - The base directory to start iterating. May not be null.

aFileFilters - The file filter to be used. May neither be null nor empty.

Returns:

Never null.