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/*
* @(#)FileChooserFilter.java 1.99.1 08/12/08
*/
// ************************************************************************
// * Copyright (c) 2008 by the Association for Computing Machinery *
// * *
// * The Java Task Force seeks to impose few restrictions on the use of *
// * these packages so that users have as much freedom as possible to *
// * use this software in constructive ways and can make the benefits of *
// * that work available to others. In view of the legal complexities *
// * of software development, however, it is essential for the ACM to *
// * maintain its copyright to guard against attempts by others to *
// * claim ownership rights. The full text of the JTF Software License *
// * is available at the following URL: *
// * *
// * http://www.acm.org/jtf/jtf-software-license.pdf *
// * *
// ************************************************************************
// REVISION HISTORY
//
// Class introduced in V1.1
package acm.util;
import java.io.*;
import java.util.*;
/* Class: FileChooserFilter */
/**
* This class extends javax.swing.filechooser.FileFilter
* and exists primarily to avoid the ambiguity that arises because there is
* also a FileFilter class in java.io. This
* class also supports simple wildcard matching of filenames.
*/
public class FileChooserFilter extends javax.swing.filechooser.FileFilter {
/* Constructor: FileChooserFilter() */
/**
* Creates a default FileChooserFilter. Such a
* FileChooserFilter is useful only if the client
* overrides the accept and getDescription
* methods.
*
* Example: FileChooserFilter filter = new FileChooserFilter();
*/
public FileChooserFilter() {
filenamePattern = null;
filenameDescription = null;
}
/* Constructor: FileChooserFilter(pattern) */
/**
* Creates a FileChooserFilter that accepts filenames
* matching the specified pattern. This pattern consists of a
* wildcard pattern (or a series of wildcard patterns separated
* by semicolons) similar to those by a Unix shell. For example, to
* match all files ending with the extensions .html
* or .htm, you could use the following constructor call:
*
*
* new FileChooserPattern("*.html;*.htm")
*
*
* Example: FileChooserFilter filter = new FileChooserFilter(pattern);
* @param pattern The filename pattern
*/
public FileChooserFilter(String pattern) {
this(pattern, pattern + " files");
}
/* Constructor: FileChooserFilter(pattern, description) */
/**
* Creates a FileChooserFilter that accepts filenames
* matching the specified pattern. This pattern consists of a
* wildcard pattern (or a series of wildcard patterns separated
* by semicolons) similar to those by a Unix shell. For example, to
* match all files ending with the extensions .html
* or .htm, you could use the following constructor call:
*
*
* new FileChooserPattern("*.html;*.htm")
*
*
* This version of the constructor makes it possible to set the
* description that appears in the dialog.
*
* Example: FileChooserFilter filter = new FileChooserFilter(pattern, description);
* @param pattern The filename pattern
* @param description The description of the files for inclusion in the dialog
*/
public FileChooserFilter(String pattern, String description) {
filenamePattern = pattern;
filenameDescription = description;
}
/* Method: accept(file) */
/**
* Returns true if the specified file should be accepted by
* the filter.
*
* Example: if (filter.accept(file)) . . .
* @param file The File object representing the file
* @return true if the specified file should be accepted
*/
public boolean accept(File file) {
if (filenamePattern == null) {
throw new ErrorException("No override definition for accept");
}
if (file.isDirectory()) return true;
StringTokenizer tokenizer = new StringTokenizer(filenamePattern, ";");
while (tokenizer.hasMoreTokens()) {
String pattern = tokenizer.nextToken();
if (pattern.length() > 0 && JTFTools.matchFilenamePattern(file.getName(), pattern)) {
return true;
}
}
return false;
}
/* Method: getDescription() */
/**
* Returns a description of the accepted files.
*/
public String getDescription() {
if (filenameDescription == null) {
throw new ErrorException("No override definition for getDescription");
}
return filenameDescription;
}
/* Private instance variables */
String filenamePattern;
String filenameDescription;
}