org.apache.tools.ant
Class DirectoryScanner

java.lang.Object
  |
  +--org.apache.tools.ant.DirectoryScanner

public class DirectoryScanner
extends java.lang.Object

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

These criteria consist of a set of include and exclude patterns. With these patterns, you can select which files you want to have included, and which files you want to have excluded.

The idea is simple. A given directory is recursively scanned for all files and directories. Each file/directory is matched against a set of include and exclude patterns. Only files/directories that match at least one pattern of the include pattern list, and don't match a pattern of the exclude pattern list 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.

The 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). E.g. "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.

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

There are special case regarding the use of File.separators at the beginningof 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 that start with "XYZ" and where there is a parent directory called test (e.g. "abc\test\def\ghi\XYZ123").

Example of usage:

   String[] includes = {"**\\*.class"};
   String[] excludes = {"modules\\*\\**"};
   ds.setIncludes(includes);
   ds.setExcludes(excludes);
   ds.setBasedir(new File("test"));
   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 .class files in all directories under a directory called "modules"

Author:
Arnout J. Kuiper ajkuiper@wxs.nl

Constructor Summary
DirectoryScanner()
          Constructor.
 
Method Summary
 void addDefaultExcludes()
          Adds the array with default exclusions to the current exclusions set.
 java.io.File getBasedir()
          Gets the basedir that is used for scanning.
 java.lang.String[] getExcludedDirectories()
          Get the names of the directories that matched at least one of the include patterns, an matched also at least one of the exclude patterns.
 java.lang.String[] getExcludedFiles()
          Get the names of the files that matched at least one of the include patterns, an matched also at least one of the exclude patterns.
 java.lang.String[] getIncludedDirectories()
          Get the names of the directories that matched at least one of the include patterns, an matched none of the exclude patterns.
 java.lang.String[] getIncludedFiles()
          Get the names of the files that matched at least one of the include patterns, an matched none of the exclude patterns.
 java.lang.String[] getNotIncludedDirectories()
          Get the names of the directories that matched at none of the include patterns.
 java.lang.String[] getNotIncludedFiles()
          Get the names of the files that matched at none of the include patterns.
 void scan()
          Scans the base directory for files that match at least one include pattern, and don't match any exclude patterns.
 void setBasedir(java.io.File basedir)
          Sets the basedir for scanning.
 void setBasedir(java.lang.String basedir)
          Sets the basedir for scanning.
 void setExcludes(java.lang.String[] excludes)
          Sets the set of exclude patterns to use.
 void setIncludes(java.lang.String[] includes)
          Sets the set of include patterns to use.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DirectoryScanner

public DirectoryScanner()
Constructor.
Method Detail

setBasedir

public void setBasedir(java.lang.String basedir)
Sets the basedir for scanning. This is the directory that is scanned recursively. All '/' and '\' characters are replaced by File.separatorChar. So the separator used need not match File.separatorChar.
Parameters:
basedir - the (non-null) basedir for scanning

setBasedir

public void setBasedir(java.io.File basedir)
Sets the basedir for scanning. This is the directory that is scanned recursively.
Parameters:
basedir - the basedir for scanning

getBasedir

public java.io.File getBasedir()
Gets the basedir that is used for scanning. This is the directory that is scanned recursively.
Returns:
the basedir that is used for scanning

setIncludes

public void setIncludes(java.lang.String[] includes)
Sets the set 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 - list of include patterns

setExcludes

public void setExcludes(java.lang.String[] excludes)
Sets the set 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 - list of exclude patterns

scan

public void scan()
Scans the base directory for files that match at least one include pattern, and don't match any exclude patterns.
Throws:
IllegalStateException - when basedir was set incorrecly

getIncludedFiles

public java.lang.String[] getIncludedFiles()
Get the names of the files that matched at least one of the include patterns, an matched none of the exclude patterns. The names are relative to the basedir.
Returns:
the names of the files

getNotIncludedFiles

public java.lang.String[] getNotIncludedFiles()
Get the names of the files that matched at none of the include patterns. The names are relative to the basedir.
Returns:
the names of the files

getExcludedFiles

public java.lang.String[] getExcludedFiles()
Get the names of the files that matched at least one of the include patterns, an matched also at least one of the exclude patterns. The names are relative to the basedir.
Returns:
the names of the files

getIncludedDirectories

public java.lang.String[] getIncludedDirectories()
Get the names of the directories that matched at least one of the include patterns, an matched none of the exclude patterns. The names are relative to the basedir.
Returns:
the names of the directories

getNotIncludedDirectories

public java.lang.String[] getNotIncludedDirectories()
Get the names of the directories that matched at none of the include patterns. The names are relative to the basedir.
Returns:
the names of the directories

getExcludedDirectories

public java.lang.String[] getExcludedDirectories()
Get the names of the directories that matched at least one of the include patterns, an matched also at least one of the exclude patterns. The names are relative to the basedir.
Returns:
the names of the directories

addDefaultExcludes

public void addDefaultExcludes()
Adds the array with default exclusions to the current exclusions set.
See Also:
#DEFAULTEXCLUDES


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