com.izforge.izpack.util.file

Class DirectoryScanner

java.lang.Object

com.izforge.izpack.util.file.DirectoryScanner

All Implemented Interfaces:

FileScanner, ResourceFactory

public class DirectoryScanner
extends Object
implements FileScanner, ResourceFactory

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"

Field Summary

Fields

Modifier and Type	Field and Description
protected static String[]	DEFAULTEXCLUDES Deprecated. use the getDefaultExcludes method instead.

Constructor Summary

Constructors

Constructor and Description
DirectoryScanner() Sole constructor.

Method Summary

Modifier and Type	Method and Description
static boolean	addDefaultExclude(String s) Add a pattern to the default excludes unless it is already a default exclude.
void	addDefaultExcludes() Add default exclusions to the current exclusions set.
void	addExcludes(String[] excludes) Add to the list of exclude patterns to use.
File	getBasedir() Return the base directory to be scanned.
String[]	getDeselectedDirectories() Return the names of the directories which were selected out and therefore not ultimately included.
String[]	getDeselectedFiles() Return the names of the files which were selected out and therefore not ultimately included.
String[]	getExcludedDirectories() Return the names of the directories which matched at least one of the include patterns and at least one of the exclude patterns.
String[]	getExcludedFiles() Return the names of the files which matched at least one of the include patterns and at least one of the exclude patterns.
String[]	getIncludedDirectories() Return the names of the directories which matched at least one of the include patterns and none of the exclude patterns.
int	getIncludedDirsCount() Return the count of included directories.
String[]	getIncludedFiles() Return the names of the files which matched at least one of the include patterns and none of the exclude patterns.
int	getIncludedFilesCount() Return the count of included files.
String[]	getNotIncludedDirectories() Return the names of the directories which matched none of the include patterns.
String[]	getNotIncludedFiles() Return the names of the files which matched none of the include patterns.
Resource	getResource(String name) Get the named resource.
boolean	isEverythingIncluded() Return whether or not the scanner has included all the files or directories it has come across so far.
boolean	isFollowSymlinks() Get whether or not a DirectoryScanner follows symbolic links.
static boolean	match(String pattern, String str) Test whether or not a string matches against a pattern.
protected static boolean	match(String pattern, String str, boolean isCaseSensitive) Test whether or not a string matches against a pattern.
protected static boolean	matchPath(String pattern, String str) Test whether or not a given path matches a given pattern.
protected static boolean	matchPatternStart(String pattern, String str) Test whether or not a given path matches the start of a given pattern up to the first "**".
static boolean	removeDefaultExclude(String s) Remove a string if it is a default exclude.
void	scan() Scan the base directory for files which match at least one include pattern and don't match any exclude patterns.
void	setBasedir(File basedir) Set the base directory to be scanned.
void	setBasedir(String basedir) Set the base directory to be scanned.
void	setCaseSensitive(boolean isCaseSensitive) Set whether or not include and exclude patterns are matched in a case sensitive way.
void	setExcludes(String[] excludes) Set the list of exclude patterns to use.
void	setFollowSymlinks(boolean followSymlinks) Set whether or not symbolic links should be followed.
void	setIncludes(String[] includes) Set the list of include patterns to use.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULTEXCLUDES

protected static final String[] DEFAULTEXCLUDES

Deprecated. use the getDefaultExcludes method instead.

Patterns which should be excluded by default.

Note that you can now add patterns to the list of default excludes. Added patterns will not become part of this array that has only been kept around for backwards compatibility reasons.

Constructor Detail

DirectoryScanner

public DirectoryScanner()

Sole constructor.

Method Detail

matchPatternStart

protected static boolean matchPatternStart(String pattern,
                                           String str)

Test 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 "**".

matchPath

protected static boolean matchPath(String pattern,
                                   String str)

Test 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.

match

public static boolean match(String pattern,
                            String str)

Test 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(String pattern,
                               String str,
                               boolean isCaseSensitive)

Test 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.

addDefaultExclude

public static boolean addDefaultExclude(String s)

Add a pattern to the default excludes unless it is already a default exclude.

Parameters:

s - A string to add as an exclude pattern.

Returns:

true if the string was added; false if it already existed.

removeDefaultExclude

public static boolean removeDefaultExclude(String s)

Remove a string if it is a default exclude.

Parameters:

s - The string to attempt to remove.

Returns:

true if s was a default exclude (and thus was removed); false if s was not in the default excludes list to begin with.

setBasedir

public void setBasedir(String basedir)

Set 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.

Specified by:

setBasedir in interface FileScanner

Parameters:

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

setBasedir

public void setBasedir(File basedir)

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

Specified by:

setBasedir in interface FileScanner

Parameters:

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

getBasedir

public File getBasedir()

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

Specified by:

getBasedir in interface FileScanner

Returns:

the base directory to be scanned

setCaseSensitive

public void setCaseSensitive(boolean isCaseSensitive)

Set whether or not include and exclude patterns are matched in a case sensitive way.

Specified by:

setCaseSensitive in interface FileScanner

Parameters:

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

isFollowSymlinks

public boolean isFollowSymlinks()

Get whether or not a DirectoryScanner follows symbolic links.

Returns:

flag indicating whether symbolic links should be followed.

setFollowSymlinks

public void setFollowSymlinks(boolean followSymlinks)

Set whether or not symbolic links should be followed.

Parameters:

followSymlinks - whether or not symbolic links should be followed.

setIncludes

public void setIncludes(String[] includes)

Set 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.

Specified by:

setIncludes in interface FileScanner

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(String[] excludes)

Set 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.

Specified by:

setExcludes in interface FileScanner

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.

addExcludes

public void addExcludes(String[] excludes)

Add to 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, in which case the exclude patterns don't get changed at all.

isEverythingIncluded

public boolean isEverythingIncluded()

Return 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 Exception

Scan 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.

Specified by:

scan in interface FileScanner

Throws:

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

getIncludedFiles

public String[] getIncludedFiles()
                          throws Exception

Return 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.

Specified by:

getIncludedFiles in interface FileScanner

Returns:

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

Throws:

Exception

getIncludedFilesCount

public int getIncludedFilesCount()
                          throws Exception

Return the count of included files.

Returns:

int.

Throws:

Exception

getNotIncludedFiles

public String[] getNotIncludedFiles()
                             throws Exception

Return 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.

Specified by:

getNotIncludedFiles in interface FileScanner

Returns:

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

Throws:

Exception

See Also:

slowScan()

getExcludedFiles

public String[] getExcludedFiles()
                          throws Exception

Return 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.

Specified by:

getExcludedFiles in interface FileScanner

Returns:

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

Throws:

Exception

See Also:

slowScan()

getDeselectedFiles

public String[] getDeselectedFiles()
                            throws Exception

Return 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.

Throws:

Exception

See Also:

slowScan()

getIncludedDirectories

public String[] getIncludedDirectories()
                                throws Exception

Return 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.

Specified by:

getIncludedDirectories in interface FileScanner

Returns:

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

Throws:

Exception

getIncludedDirsCount

public int getIncludedDirsCount()
                         throws Exception

Return the count of included directories.

Returns:

int.

Throws:

Exception

getNotIncludedDirectories

public String[] getNotIncludedDirectories()
                                   throws Exception

Return 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.

Specified by:

getNotIncludedDirectories in interface FileScanner

Returns:

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

Throws:

Exception

See Also:

slowScan()

getExcludedDirectories

public String[] getExcludedDirectories()
                                throws Exception

Return 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.

Specified by:

getExcludedDirectories in interface FileScanner

Returns:

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

Throws:

Exception

See Also:

slowScan()

getDeselectedDirectories

public String[] getDeselectedDirectories()
                                  throws Exception

Return 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.

Throws:

Exception

See Also:

slowScan()

addDefaultExcludes

public void addDefaultExcludes()

Add default exclusions to the current exclusions set.

Specified by:

addDefaultExcludes in interface FileScanner

getResource

public Resource getResource(String name)
                     throws Exception

Get the named resource.

Specified by:

getResource in interface ResourceFactory

Parameters:

name - path name of the file relative to the dir attribute.

Returns:

the resource with the given name.

Throws:

Exception