io/filefilter/package.html

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<p>This package defines an interface (IOFileFilter) that combines both
{@link java.io.FileFilter} and {@link java.io.FilenameFilter}. Besides
that the package offers a series of ready-to-use implementations of the
IOFileFilter interface including implementation that allow you to combine
other such filters.</p>
<p>These filter can be used to list files or in {@link java.awt.FileDialog},
for example.</p>

<p>There are a number of 'primitive' filters:</p>

<table>
       <tbody>
    <tr>
      <td><a href="DirectoryFileFilter.html">DirectoryFilter</a></td>
      <td>Only accept directories</td>
    </tr>
       <tr>
      <td><a href="PrefixFileFilter.html">PrefixFileFilter</a></td>
      <td>Filter based on a prefix</td>
    </tr>
       <tr>
      <td><a href="SuffixFileFilter.html">SuffixFileFilter</a></td>
      <td>Filter based on a suffix</td>
    </tr>
    <tr>
      <td><a href="NameFileFilter.html">NameFileFilter</a></td>
      <td>Filter based on a filename</td>
    </tr>
    <tr>
      <td><a href="WildcardFileFilter.html">WildcardFileFilter</a></td>
      <td>Filter based on wildcards</td>
    </tr>
    <tr>
      <td><a href="AgeFileFilter.html">AgeFileFilter</a></td>
      <td>Filter based on last modified time of file</td>
    </tr>
    <tr>
      <td><a href="SizeFileFilter.html">SizeFileFilter</a></td>
      <td>Filter based on file size</td>
    </tr>
  </tbody>
</table>

<p>And there are five 'boolean' filters:</p>

<table>
       <tbody>
       <tr>
      <td><a href="TrueFileFilter.html">TrueFileFilter</a></td>
      <td>Accept all files</td>
    </tr>
       <tr>
      <td><a href="FalseFileFilter.html">FalseFileFilter</a></td>
      <td>Accept no files</td>
    </tr>
       <tr>
      <td><a href="NotFileFilter.html">NotFileFilter</a></td>
      <td>Applies a logical NOT to an existing filter</td>
    </tr>
    <tr>
      <td><a href="AndFileFilter.html">AndFileFilter</a></td>
      <td>Combines two filters using a logical AND</td>
    </tr>
       <tr>
      <td><a href="OrFileFilter.html">OrFileFilter</a></td>
      <td>Combines two filter using a logical OR</td>
    </tr>

  </tbody>
</table>

<p>These boolean FilenameFilters can be nested, to allow arbitrary expressions.
For example, here is how one could print all non-directory files in the
current directory, starting with "A", and ending in ".java" or ".class":</p>

<pre>
  File dir = new File(".");
  String[] files = dir.list(
    new AndFileFilter(
      new AndFileFilter(
        new PrefixFileFilter("A"),
        new OrFileFilter(
          new SuffixFileFilter(".class"),
          new SuffixFileFilter(".java")
        )
      ),
      new NotFileFilter(
        new DirectoryFileFilter()
      )
    )
  );
  for ( int i=0; i&lt;files.length; i++ ) {
    System.out.println(files[i]);
  }
</pre>

<p>This package also contains a utility class:
<a href="FileFilterUtils.html">FileFilterUtils</a>. It allows you to use all
file filters without having to put them in the import section. Here's how the
above example will look using FileFilterUtils:</p>
<pre>
  File dir = new File(".");
  String[] files = dir.list(
    FileFilterUtils.andFileFilter(
      FileFilterUtils.andFileFilter(
        FileFilterUtils.prefixFileFilter("A"),
        FileFilterUtils.orFileFilter(
          FileFilterUtils.suffixFileFilter(".class"),
          FileFilterUtils.suffixFileFilter(".java")
        )
      ),
      FileFilterUtils.notFileFilter(
        FileFilterUtils.directoryFileFilter()
      )
    )
  );
  for ( int i=0; i&lt;files.length; i++ ) {
    System.out.println(files[i]);
  }
</pre>
<p>There are a few other goodies in that class so please have a look at the
documentation in detail.</p>
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