Package 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<String>

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

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected String
    basedir
    The base directory to be scanned.
    static final 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

    Constructors
    Constructor
    Description
    ListScanner()
    Sole constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    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 a name matches 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(String excludes)
     
    void
    setExcludes(List<String> excludesList)
    Sets the list of exclude patterns to use.
    void
    setIncludes(String includes)
     
    void
    setIncludes(List<String> includesList)
    Sets 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 Details

    • DEFAULTEXCLUDES

      public static final String[] DEFAULTEXCLUDES
      Patterns which should be excluded by default.
      See Also:

    • 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 Details

    • ListScanner

      public ListScanner()
      Sole constructor.

  • Method Details

    • 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:
      excludesList - 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:
      includesList - 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 a name matches 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.