Java JFileChooser chooseOpenFile(String dir, String fileName, String fileNameExtension, Component parent)

Description

Opens a file chooser and returns the selected file if available.

License

Open Source License

Parameter

Parameter	Description
dir	The directory from which a file will be selected.
fileName	The initial file name that is prompted in the file field.
fileNameExtension	The desired file extension.
parent	The parent component that makes the call.

Return

An instance of if the selection is successful, null otherwise.

Declaration

public static File chooseOpenFile(String dir, String fileName, String fileNameExtension, Component parent) 

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.awt.Component;

import java.io.File;

import javax.swing.JFileChooser;

import javax.swing.JOptionPane;

import javax.swing.filechooser.FileNameExtensionFilter;

public class Main {
    /**//  w w  w  .  j a v  a  2 s.  co m
     * Opens a file chooser and returns the selected file if available. 
     * 
     * @param dir            The directory from which a file will be selected.
     * @param fileName         The initial file name that is prompted in the file field.
     * @param fileNameExtension   The desired file extension.
     * @param parent The parent component that makes the call.
     * 
     * @return An instance of {@link File} if the selection is successful, <code>null</code> otherwise.
     */
    public static File chooseOpenFile(String dir, String fileName, String fileNameExtension, Component parent) {
        JFileChooser chooser = new JFileChooser();
        File selectedFile = null;

        File fileDir = null;

        // if dir is not specified or the dir doesn't exist, use the current directory
        if (dir == null) {
            fileDir = new File(".");
        } else {
            fileDir = new File(dir);
        }

        if (!fileDir.exists()) {
            fileDir = new File(".");
        }

        chooser.setCurrentDirectory(fileDir);

        if (fileName != null) {
            chooser.setSelectedFile(new java.io.File(fileName));
        }

        if (fileNameExtension != null) {
            chooser.setFileFilter(new FileNameExtensionFilter(fileNameExtension + " file", fileNameExtension));
        }
        chooser.setDialogTitle("Open File");

        boolean isValid = true;
        do {
            int chooserState = chooser.showDialog(parent, "Ok");
            if (chooserState == JFileChooser.APPROVE_OPTION) {
                selectedFile = chooser.getSelectedFile();
                if (!selectedFile.exists()) {
                    JOptionPane.showMessageDialog(parent,
                            selectedFile.getName() + " does not exist. Please choose another file!",
                            "File Not Found", JOptionPane.WARNING_MESSAGE);
                } else {
                    isValid = false;
                }
            } else {
                return null;
            }
        } while (isValid);

        return selectedFile;
    }
}

Related

1. chooseFiles(final Component parent)
2. chooseFiles(String title, File currentDir)
3. chooseFilesForOpen(String title, FileFilter filter, File initialDir)
4. chooseFileToRead(Component owner, FileFilter filter, File pathToNavigateTo)
5. chooseNewFile(final Component parent, final File startingDirectory)
6. chooseSaveFile(Component parent, File defaultFile, FileFilter filter)
7. chooseSaveFile(String dir, String initialFile, String fileNameExtension, Component parent)
8. choseFile(File selectedFile, String startDir, final String description, final String extension, Component parent, boolean addExtension, boolean forLoad)
9. cleanFileSelector(JFileChooser filterUpdates)