利用正则表达式列出匹配的文件名

// : c12:DirList.Java

// Displays Directory listing using regular eXPressions.

// {Args: "D.*\.java"}

// From 'Thinking in Java, 3rd ed.' (c) BrUCe Eckel 2002

// www.BruceEckel.com. See copyright notice in CopyRight.txt.

import java.io.File;

import java.io.FilenameFilter;

import java.util.Arrays;

import java.util.Comparator;

import java.util.regex.Pattern;

public class DirList {

public static void main(String[] args) {

File path = new File(".");

String[] list;

if (args.length == 0)

list = path.list();

else

list = path.list(new DirFilter(args[0]));

Arrays.sort(list, new AlphabeticComparator());

for (int i = 0; i < list.length; i++)

System.out.println(list[i]);

}

}

class DirFilter implements FilenameFilter {

private Pattern pattern;

public DirFilter(String regex) {

pattern = Pattern.compile(regex);

}

public boolean accept(File dir, String name) {

// Strip path information, search for regex:

return pattern.matcher(new File(name).getName()).matches();

}

} ///:~

class AlphabeticComparator implements Comparator {

public int compare(Object o1, Object o2) {

String s1 = (String) o1;

String s2 = (String) o2;

return s1.toLowerCase().compareTo(s2.toLowerCase());

}

} ///:~