org.apache.maven.archetype.common.util
Class ListScanner

java.lang.Object
  org.apache.maven.archetype.common.util.ListScanner

public class ListScanner
extends 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"

This class was stealed from rg.coudehaus.plexus.util.DirectoryScanner and adapted to search from a List

Author:

Arnout J. Kuiper ajkuiper@wxs.nl, Magesh Umasankar, Bruce Atherton, Antoine Levy-Lambert

Field Summary

protected String	basedir The base directory to be scanned.
static String[]	DEFAULTEXCLUDES Patterns which should be excluded by default.
protected boolean	everythingIncluded Whether or not everything tested so far has been included.
protected String[]	excludes The patterns for the files to be excluded.
protected 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

ListScanner()
Sole constructor.

Method Summary

void	addDefaultExcludes() Adds default exclusions to the current exclusions set.
String	getBasedir() Returns the base directory to be scanned.
static String	getDefaultExcludes()
protected boolean	isExcluded(String name) Tests whether or not a name matches against at least one exclude pattern.
protected boolean	isIncluded(String name) Tests whether or not a name matches against at least one include pattern.
static boolean	match(String pattern, String str) Tests whether or not a string matches against a pattern.
protected static boolean	match(String pattern, String str, boolean isCaseSensitive) Tests whether or not a string matches against a pattern.
protected boolean	matchesPatterns(String name, String[] patterns) Tests whether or not a name matches against at least one include pattern.
protected static boolean	matchPath(String pattern, String str) Tests whether or not a given path matches a given pattern.
protected static boolean	matchPath(String pattern, String str, boolean isCaseSensitive) Tests whether or not a given path matches a given pattern.
protected static boolean	matchPatternStart(String pattern, String str) Tests whether or not a given path matches the start of a given pattern up to the first "**".
protected static boolean	matchPatternStart(String pattern, String str, boolean isCaseSensitive) Tests whether or not a given path matches the start of a given pattern up to the first "**".
List<String>	scan(List<String> files) Scans the base directory for files which match at least one include pattern and don't match any exclude patterns.
void	setBasedir(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(List<String> excludesList) Sets the list of exclude patterns to use.
void	setExcludes(String excludes)
void	setIncludes(List<String> includesList) Sets the list of include patterns to use.
void	setIncludes(String includes)

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULTEXCLUDES

public static final String[] DEFAULTEXCLUDES

Patterns which should be excluded by default.

See Also:

addDefaultExcludes()

basedir

protected String basedir

The base directory to be scanned.

everythingIncluded

protected boolean everythingIncluded

Whether or not everything tested so far has been included.

excludes

protected String[] excludes

The patterns for the files to be excluded.

includes

protected String[] includes

The patterns for the files to be included.

isCaseSensitive

protected boolean isCaseSensitive

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

Constructor Detail

ListScanner

public ListScanner()

Sole constructor.

Method Detail

getDefaultExcludes

public static String getDefaultExcludes()

match

public static boolean match(String pattern,
                            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(String pattern,
                               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.

matchPath

protected static boolean matchPath(String pattern,
                                   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(String pattern,
                                   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.

matchPatternStart

protected static boolean matchPatternStart(String pattern,
                                           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(String pattern,
                                           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 "**".

addDefaultExcludes

public void addDefaultExcludes()

Adds default exclusions to the current exclusions set.

getBasedir

public String getBasedir()

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

Returns:

the base directory to be scanned

setBasedir

public void setBasedir(String basedir)

Sets the base directory to be scanned. This is the directory which is scanned recursively. This directory is normalized for multiple os's (all / and \\ are replaced with File.separatorChar

Parameters:

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

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

setExcludes

public void setExcludes(List<String> excludesList)

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.

setExcludes

public void setExcludes(String excludes)

setIncludes

public void setIncludes(List<String> includesList)

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.

setIncludes

public void setIncludes(String includes)

scan

public List<String> scan(List<String> files)
                  throws 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:

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

isExcluded

protected boolean isExcluded(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.

isIncluded

protected boolean isIncluded(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.

matchesPatterns

protected boolean matchesPatterns(String name,
                                  String[] patterns)

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

Parameters:

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

patterns - The list of patterns to match.

Returns:

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