Java IO.pdf - Nguyen Dang Binh

Java I/O
the following lines of code list HTML files in the /public/html/javafaq directory using
the HTMLFilter of Example 12.6.
File dir = new File("/public/html/javafaq");
File[] htmlFiles = dir.listFiles(new HTMLFilter());
for (int i = 0; i < htmlFiles.length; i++) {
System.out.println(htmlFiles[i]);
}
12.5 File Filters
Java 2 adds a new java.io.FileFilter interface that's very similar to FilenameFilter:
public abstract interface FileFilter // Java 2
The accept() method of FileFilter takes a single File object as an argument, rather than
two strings giving the directory and path:
public boolean accept(File pathname) // Java 2
Example 12.7 is a filter that only passes HTML files. Its logic is essentially the same as the
filter of Example 12.6.
Example 12.7. HTMLFileFilter
import java.io.*;
public class HTMLFileFilter implements FileFilter {
}
}
public boolean accept(File pathname) {
if (pathname.getName().endsWith(".html")) return true;
if (pathname.getName().endsWith(".htm")) return true;
return false;
This class appears as an argument in one of the listFiles() methods of java.io.File:
public File[] listFiles(FileFilter filter) // Java 2
Example 12.8 uses the HTMLFileFilter to list the HTML files in the current working
directory.
Example 12.8. List HTML Files
import java.io.*;
public class HTMLFiles {
public static void main(String[] args) {
File cwd = new File(System.getProperty("user.dir"));
File[] htmlFiles = cwd.listFiles(new HTMLFileFilter());
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