Mega Code Archive
Displays directory listing using regular expressions
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// : 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());
}
} ///:~
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