org.codehaus.plexus.util
Class DirectoryScanner

java.lang.Object
  org.codehaus.plexus.util.DirectoryScanner

public class DirectoryScanner
extends java.lang.Object

Class for scanning a directory for files/directories which match certain criteria.

These criteria consist of selectors and patterns which have been specified. With the selectors you can select which files you want to have included. Files which are not selected are excluded. With patterns you can include or exclude files based on their filename.

The idea is simple. A given directory is recursively scanned for all files and directories. Each file/directory is matched against a set of selectors, including special support for matching against filenames with include and and exclude patterns. Only files/directories which match at least one pattern of the include pattern list or other file selector, and don't match any pattern of the exclude pattern list or fail to match against a required selector will be placed in the list of files/directories found.

When no list of include patterns is supplied, "**" will be used, which means that everything will be matched. When no list of exclude patterns is supplied, an empty list is used, such that nothing will be excluded. When no selectors are supplied, none are applied.

The filename pattern matching is done as follows: The name to be matched is split up in path segments. A path segment is the name of a directory or file, which is bounded by File.separator ('/' under UNIX, '\' under Windows). For example, "abc/def/ghi/xyz.java" is split up in the segments "abc", "def","ghi" and "xyz.java". The same is done for the pattern against which should be matched.

The segments of the name and the pattern are then matched against each other. When '**' is used for a path segment in the pattern, it matches zero or more path segments of the name.

There is a special case regarding the use of File.separators at the beginning of the pattern and the string to match:
When a pattern starts with a File.separator, the string to match must also start with a File.separator. When a pattern does not start with a File.separator, the string to match may not start with a File.separator. When one of these rules is not obeyed, the string will not match.

When a name path segment is matched against a pattern path segment, the following special characters can be used:
'*' matches zero or more characters
'?' matches one character.

Examples:

"**\*.class" matches all .class files/dirs in a directory tree.

"test\a??.java" matches all files/dirs which start with an 'a', then two more characters and then ".java", in a directory called test.

"**" matches everything in a directory tree.

"**\test\**\XYZ*" matches all files/dirs which start with "XYZ" and where there is a parent directory called test (e.g. "abc\test\def\ghi\XYZ123").

Case sensitivity may be turned off if necessary. By default, it is turned on.

Example of usage:

   String[] includes = {"*\*\*.class"};
   String[] excludes = {"modules\\\*\**"};
   ds.setIncludes(includes);
   ds.setExcludes(excludes);
   ds.setBasedir(new File("test"));
   ds.setCaseSensitive(true);
   ds.scan();

   System.out.println("FILES:");
   String[] files = ds.getIncludedFiles();
   for (int i = 0; i < files.length; i++) {
     System.out.println(files[i]);
   }
 

This will scan a directory called test for .class files, but excludes all files in all proper subdirectories of a directory called "modules"

Author:

Arnout J. Kuiper [email protected], Magesh Umasankar, Bruce Atherton, Antoine Levy-Lambert

Field Summary

protected java.io.File	basedir The base directory to be scanned.
static java.lang.String[]	DEFAULTEXCLUDES Patterns which should be excluded by default.
protected java.util.Vector	dirsDeselected The directories which matched at least one include and no excludes but which a selector discarded.
protected java.util.Vector	dirsExcluded The directories which matched at least one include and at least one exclude.
protected java.util.Vector	dirsIncluded The directories which matched at least one include and no excludes and were selected.
protected java.util.Vector	dirsNotIncluded The directories which were found and did not match any includes.
protected boolean	everythingIncluded Whether or not everything tested so far has been included.
protected java.lang.String[]	excludes The patterns for the files to be excluded.
protected java.util.Vector	filesDeselected The files which matched at least one include and no excludes and which a selector discarded.
protected java.util.Vector	filesExcluded The files which matched at least one include and at least one exclude.
protected java.util.Vector	filesIncluded The files which matched at least one include and no excludes and were selected.
protected java.util.Vector	filesNotIncluded The files which did not match any includes or selectors.
protected boolean	haveSlowResults Whether or not our results were built by a slow scan.
protected java.lang.String[]	includes The patterns for the files to be included.
protected boolean	isCaseSensitive Whether or not the file system should be treated as a case sensitive one.

Constructor Summary

DirectoryScanner()
Sole constructor.

Method Summary

void	addDefaultExcludes() Adds default exclusions to the current exclusions set.
protected boolean	couldHoldIncluded(java.lang.String name) Tests whether or not a name matches the start of at least one include pattern.
java.io.File	getBasedir() Returns the base directory to be scanned.
java.lang.String[]	getDeselectedDirectories() Returns the names of the directories which were selected out and therefore not ultimately included.
java.lang.String[]	getDeselectedFiles() Returns the names of the files which were selected out and therefore not ultimately included.
java.lang.String[]	getExcludedDirectories() Returns the names of the directories which matched at least one of the include patterns and at least one of the exclude patterns.
java.lang.String[]	getExcludedFiles() Returns the names of the files which matched at least one of the include patterns and at least one of the exclude patterns.
java.lang.String[]	getIncludedDirectories() Returns the names of the directories which matched at least one of the include patterns and none of the exclude patterns.
java.lang.String[]	getIncludedFiles() Returns the names of the files which matched at least one of the include patterns and none of the exclude patterns.
java.lang.String[]	getNotIncludedDirectories() Returns the names of the directories which matched none of the include patterns.
java.lang.String[]	getNotIncludedFiles() Returns the names of the files which matched none of the include patterns.
boolean	isEverythingIncluded() Returns whether or not the scanner has included all the files or directories it has come across so far.
protected boolean	isExcluded(java.lang.String name) Tests whether or not a name matches against at least one exclude pattern.
protected boolean	isIncluded(java.lang.String name) Tests whether or not a name matches against at least one include pattern.
protected boolean	isSelected(java.lang.String name, java.io.File file) Tests whether a name should be selected.
boolean	isSymbolicLink(java.io.File parent, java.lang.String name) Checks whether a given file is a symbolic link.
static boolean	match(java.lang.String pattern, java.lang.String str) Tests whether or not a string matches against a pattern.
protected static boolean	match(java.lang.String pattern, java.lang.String str, boolean isCaseSensitive) Tests whether or not a string matches against a pattern.
protected static boolean	matchPath(java.lang.String pattern, java.lang.String str) Tests whether or not a given path matches a given pattern.
protected static boolean	matchPath(java.lang.String pattern, java.lang.String str, boolean isCaseSensitive) Tests whether or not a given path matches a given pattern.
protected static boolean	matchPatternStart(java.lang.String pattern, java.lang.String str) Tests whether or not a given path matches the start of a given pattern up to the first "**".
protected static boolean	matchPatternStart(java.lang.String pattern, java.lang.String str, boolean isCaseSensitive) Tests whether or not a given path matches the start of a given pattern up to the first "**".
void	scan() Scans the base directory for files which match at least one include pattern and don't match any exclude patterns.
protected void	scandir(java.io.File dir, java.lang.String vpath, boolean fast) Scans the given directory for files and directories.
void	setBasedir(java.io.File basedir) Sets the base directory to be scanned.
void	setBasedir(java.lang.String basedir) Sets the base directory to be scanned.
void	setCaseSensitive(boolean isCaseSensitive) Sets whether or not the file system should be regarded as case sensitive.
void	setExcludes(java.lang.String[] excludes) Sets the list of exclude patterns to use.
void	setFollowSymlinks(boolean followSymlinks) Sets whether or not symbolic links should be followed.
void	setIncludes(java.lang.String[] includes) Sets the list of include patterns to use.
protected void	slowScan() Top level invocation for a slow scan.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULTEXCLUDES

public static final java.lang.String[] DEFAULTEXCLUDES

Patterns which should be excluded by default.

See Also:

addDefaultExcludes()

basedir

protected java.io.File basedir

The base directory to be scanned.

includes

protected java.lang.String[] includes

The patterns for the files to be included.

excludes

protected java.lang.String[] excludes

The patterns for the files to be excluded.

filesIncluded

protected java.util.Vector filesIncluded

The files which matched at least one include and no excludes and were selected.

filesNotIncluded

protected java.util.Vector filesNotIncluded

The files which did not match any includes or selectors.

filesExcluded

protected java.util.Vector filesExcluded

The files which matched at least one include and at least one exclude.

dirsIncluded

protected java.util.Vector dirsIncluded

The directories which matched at least one include and no excludes and were selected.

dirsNotIncluded

protected java.util.Vector dirsNotIncluded

The directories which were found and did not match any includes.

dirsExcluded

protected java.util.Vector dirsExcluded

The directories which matched at least one include and at least one exclude.

filesDeselected

protected java.util.Vector filesDeselected

The files which matched at least one include and no excludes and which a selector discarded.

dirsDeselected

protected java.util.Vector dirsDeselected

The directories which matched at least one include and no excludes but which a selector discarded.

haveSlowResults

protected boolean haveSlowResults

Whether or not our results were built by a slow scan.

isCaseSensitive

protected boolean isCaseSensitive

Whether or not the file system should be treated as a case sensitive one.

everythingIncluded

protected boolean everythingIncluded

Whether or not everything tested so far has been included.

Constructor Detail

DirectoryScanner

public DirectoryScanner()

Sole constructor.

Method Detail

matchPatternStart

protected static boolean matchPatternStart(java.lang.String pattern,
                                           java.lang.String str)

Tests whether or not a given path matches the start of a given pattern up to the first "**".

This is not a general purpose test and should only be used if you can live with false positives. For example, pattern=**\a and str=b will yield true.

Parameters:

pattern - The pattern to match against. Must not be null.

str - The path to match, as a String. Must not be null.

Returns:

whether or not a given path matches the start of a given pattern up to the first "**".

matchPatternStart

protected static boolean matchPatternStart(java.lang.String pattern,
                                           java.lang.String str,
                                           boolean isCaseSensitive)

Tests whether or not a given path matches the start of a given pattern up to the first "**".

This is not a general purpose test and should only be used if you can live with false positives. For example, pattern=**\a and str=b will yield true.

Parameters:

pattern - The pattern to match against. Must not be null.

str - The path to match, as a String. Must not be null.

isCaseSensitive - Whether or not matching should be performed case sensitively.

Returns:

whether or not a given path matches the start of a given pattern up to the first "**".

matchPath

protected static boolean matchPath(java.lang.String pattern,
                                   java.lang.String str)

Tests whether or not a given path matches a given pattern.

Parameters:

pattern - The pattern to match against. Must not be null.

str - The path to match, as a String. Must not be null.

Returns:

true if the pattern matches against the string, or false otherwise.

matchPath

protected static boolean matchPath(java.lang.String pattern,
                                   java.lang.String str,
                                   boolean isCaseSensitive)

Tests whether or not a given path matches a given pattern.

Parameters:

pattern - The pattern to match against. Must not be null.

str - The path to match, as a String. Must not be null.

isCaseSensitive - Whether or not matching should be performed case sensitively.

Returns:

true if the pattern matches against the string, or false otherwise.

match

public static boolean match(java.lang.String pattern,
                            java.lang.String str)

Tests whether or not a string matches against a pattern. The pattern may contain two special characters:
'*' means zero or more characters
'?' means one and only one character

Parameters:

pattern - The pattern to match against. Must not be null.

str - The string which must be matched against the pattern. Must not be null.

Returns:

true if the string matches against the pattern, or false otherwise.

match

protected static boolean match(java.lang.String pattern,
                               java.lang.String str,
                               boolean isCaseSensitive)

Tests whether or not a string matches against a pattern. The pattern may contain two special characters:
'*' means zero or more characters
'?' means one and only one character

Parameters:

pattern - The pattern to match against. Must not be null.

str - The string which must be matched against the pattern. Must not be null.

isCaseSensitive - Whether or not matching should be performed case sensitively.

Returns:

true if the string matches against the pattern, or false otherwise.

setBasedir

public void setBasedir(java.lang.String basedir)

Sets the base directory to be scanned. This is the directory which is scanned recursively. All '/' and '\' characters are replaced by File.separatorChar, so the separator used need not match File.separatorChar.

Parameters:

basedir - The base directory to scan. Must not be null.

setBasedir

public void setBasedir(java.io.File basedir)

Sets the base directory to be scanned. This is the directory which is scanned recursively.

Parameters:

basedir - The base directory for scanning. Should not be null.

getBasedir

public java.io.File getBasedir()

Returns the base directory to be scanned. This is the directory which is scanned recursively.

Returns:

the base directory to be scanned

setCaseSensitive

public void setCaseSensitive(boolean isCaseSensitive)

Sets whether or not the file system should be regarded as case sensitive.

Parameters:

isCaseSensitive - whether or not the file system should be regarded as a case sensitive one

setFollowSymlinks

public void setFollowSymlinks(boolean followSymlinks)

Sets whether or not symbolic links should be followed.

Parameters:

followSymlinks - whether or not symbolic links should be followed

setIncludes

public void setIncludes(java.lang.String[] includes)

Sets the list of include patterns to use. All '/' and '\' characters are replaced by File.separatorChar, so the separator used need not match File.separatorChar.

When a pattern ends with a '/' or '\', "**" is appended.

Parameters:

includes - A list of include patterns. May be null, indicating that all files should be included. If a non-null list is given, all elements must be non-null.

setExcludes

public void setExcludes(java.lang.String[] excludes)

Sets the list of exclude patterns to use. All '/' and '\' characters are replaced by File.separatorChar, so the separator used need not match File.separatorChar.

When a pattern ends with a '/' or '\', "**" is appended.

Parameters:

excludes - A list of exclude patterns. May be null, indicating that no files should be excluded. If a non-null list is given, all elements must be non-null.

isEverythingIncluded

public boolean isEverythingIncluded()

Returns whether or not the scanner has included all the files or directories it has come across so far.

Returns:

true if all files and directories which have been found so far have been included.

scan

public void scan()
          throws java.lang.IllegalStateException

Scans the base directory for files which match at least one include pattern and don't match any exclude patterns. If there are selectors then the files must pass muster there, as well.

Throws:

java.lang.IllegalStateException - if the base directory was set incorrectly (i.e. if it is null, doesn't exist, or isn't a directory).

slowScan

protected void slowScan()

Top level invocation for a slow scan. A slow scan builds up a full list of excluded/included files/directories, whereas a fast scan will only have full results for included files, as it ignores directories which can't possibly hold any included files/directories.

Returns immediately if a slow scan has already been completed.

scandir

protected void scandir(java.io.File dir,
                       java.lang.String vpath,
                       boolean fast)

Scans the given directory for files and directories. Found files and directories are placed in their respective collections, based on the matching of includes, excludes, and the selectors. When a directory is found, it is scanned recursively.

Parameters:

dir - The directory to scan. Must not be null.

vpath - The path relative to the base directory (needed to prevent problems with an absolute path when using dir). Must not be null.

fast - Whether or not this call is part of a fast scan.

Throws:

java.io.IOException

See Also:

filesIncluded, filesNotIncluded, filesExcluded, dirsIncluded, dirsNotIncluded, dirsExcluded, slowScan()

isIncluded

protected boolean isIncluded(java.lang.String name)

Tests whether or not a name matches against at least one include pattern.

Parameters:

name - The name to match. Must not be null.

Returns:

true when the name matches against at least one include pattern, or false otherwise.

couldHoldIncluded

protected boolean couldHoldIncluded(java.lang.String name)

Tests whether or not a name matches the start of at least one include pattern.

Parameters:

name - The name to match. Must not be null.

Returns:

true when the name matches against the start of at least one include pattern, or false otherwise.

isExcluded

protected boolean isExcluded(java.lang.String name)

Tests whether or not a name matches against at least one exclude pattern.

Parameters:

name - The name to match. Must not be null.

Returns:

true when the name matches against at least one exclude pattern, or false otherwise.

isSelected

protected boolean isSelected(java.lang.String name,
                             java.io.File file)

Tests whether a name should be selected.

Parameters:

name - the filename to check for selecting

file - the java.io.File object for this filename

Returns:

false when the selectors says that the file should not be selected, true otherwise.

getIncludedFiles

public java.lang.String[] getIncludedFiles()

Returns the names of the files which matched at least one of the include patterns and none of the exclude patterns. The names are relative to the base directory.

Returns:

the names of the files which matched at least one of the include patterns and none of the exclude patterns.

getNotIncludedFiles

public java.lang.String[] getNotIncludedFiles()

Returns the names of the files which matched none of the include patterns. The names are relative to the base directory. This involves performing a slow scan if one has not already been completed.

Returns:

the names of the files which matched none of the include patterns.

See Also:

slowScan()

getExcludedFiles

public java.lang.String[] getExcludedFiles()

Returns the names of the files which matched at least one of the include patterns and at least one of the exclude patterns. The names are relative to the base directory. This involves performing a slow scan if one has not already been completed.

Returns:

the names of the files which matched at least one of the include patterns and at at least one of the exclude patterns.

See Also:

slowScan()

getDeselectedFiles

public java.lang.String[] getDeselectedFiles()

Returns the names of the files which were selected out and therefore not ultimately included.

The names are relative to the base directory. This involves performing a slow scan if one has not already been completed.

Returns:

the names of the files which were deselected.

See Also:

slowScan()

getIncludedDirectories

public java.lang.String[] getIncludedDirectories()

Returns the names of the directories which matched at least one of the include patterns and none of the exclude patterns. The names are relative to the base directory.

Returns:

the names of the directories which matched at least one of the include patterns and none of the exclude patterns.

getNotIncludedDirectories

public java.lang.String[] getNotIncludedDirectories()

Returns the names of the directories which matched none of the include patterns. The names are relative to the base directory. This involves performing a slow scan if one has not already been completed.

Returns:

the names of the directories which matched none of the include patterns.

See Also:

slowScan()

getExcludedDirectories

public java.lang.String[] getExcludedDirectories()

Returns the names of the directories which matched at least one of the include patterns and at least one of the exclude patterns. The names are relative to the base directory. This involves performing a slow scan if one has not already been completed.

Returns:

the names of the directories which matched at least one of the include patterns and at least one of the exclude patterns.

See Also:

slowScan()

getDeselectedDirectories

public java.lang.String[] getDeselectedDirectories()

Returns the names of the directories which were selected out and therefore not ultimately included.

The names are relative to the base directory. This involves performing a slow scan if one has not already been completed.

Returns:

the names of the directories which were deselected.

See Also:

slowScan()

addDefaultExcludes

public void addDefaultExcludes()

Adds default exclusions to the current exclusions set.

isSymbolicLink

public boolean isSymbolicLink(java.io.File parent,
                              java.lang.String name)
                       throws java.io.IOException

Checks whether a given file is a symbolic link.

It doesn't really test for symbolic links but whether the canonical and absolute paths of the file are identical - this may lead to false positives on some platforms.

Parameters:

parent - the parent directory of the file to test

name - the name of the file to test.

Throws:

java.io.IOException

Since:

Ant 1.5