* File home = new File (System.getProperty("user.home") + File.separator + "lib");
* File toAdd = new FileChooserBuilder ("libraries-dir").setTitle("Add Library").
* setDefaultWorkingDirectory(home).setApproveText("Add").showOpenDialog();
* if (toAdd != null) {
* //do something
* }
*
* Instances of this class are intended to be thrown away after use. Typically
* you create a builder, set it to create file choosers as you wish, then
* use it to show a dialog or create a file chooser you then do something
* with.
* * Supports the most common subset of JFileChooser functionality; if you * need to do something exotic with a file chooser, you are probably better * off creating your own. * * @author Tim Boudreau */ public class FileChooserBuilder { private boolean dirsOnly; private BadgeProvider badger; private String title; private String approveText; //Just in case... private boolean preventSymlinkTraversal = !Boolean.getBoolean("allow.filechooser.symlink.traversal"); //NOI18N private final String dirKey; private File failoverDir; private FileFilter filter; private boolean fileHiding; private boolean controlButtonsShown = true; private String aDescription; private boolean filesOnly; /** * Create a new FileChooserBuilder using the name of the passed class * as the metadata for looking up a starting directory from previous * application sessions or invocations. * @param type A non-null class object, typically the calling class */ public FileChooserBuilder(Class type) { this(type.getName()); } /** * Create a new FileChooserBuilder. The passed key is used as a key * into NbPreferences to look up the directory the file chooser should * initially be rooted on. * * @param dirKey A non-null ad-hoc string. If a FileChooser was previously * used with the same string as is passed, then the initial directory */ public FileChooserBuilder(String dirKey) { if (dirKey == null) { throw new NullPointerException("Null key"); } this.dirKey = dirKey; } /** * Set whether or not any file choosers created by this builder will show * only directories. * @param val true if files should not be shown * @return this */ public FileChooserBuilder setDirectoriesOnly(boolean val) { dirsOnly = val; assert !filesOnly : "FilesOnly and DirsOnly are mutually exclusive"; return this; } public FileChooserBuilder setFilesOnly(boolean val) { filesOnly = val; assert !dirsOnly : "FilesOnly and DirsOnly are mutually exclusive"; return this; } /** * Provide an implementation of BadgeProvider which will "badge" the * icons of some files. * * @param provider A badge provider which will alter the icon of files * or folders that may be of particular interest to the user * @return */ public FileChooserBuilder setBadgeProvider(BadgeProvider provider) { this.badger = provider; return this; } /** * Set the dialog title for any JFileChoosers created by this builder. * @param val A localized, human-readable title * @return this */ public FileChooserBuilder setTitle(String val) { title = val; return this; } /** * Set the text on the OK button for any file chooser dialogs produced * by this builder. * @param val A short, localized, human-readable string * @return this */ public FileChooserBuilder setApproveText(String val) { approveText = val; return this; } /** * Set a file filter which filters the list of selectable files. * @param filter * @return */ public FileChooserBuilder setFileFilter (FileFilter filter) { this.filter = filter; return this; } /** * Set the current directory which should be used only if * a last-used directory cannot be found for the key string passed * into this builder's constructor. * @param dir A directory to root any created file choosers on if * there is no stored path for this builder's key * @return this */ public FileChooserBuilder setDefaultWorkingDirectory (File dir) { failoverDir = dir; return this; } /** * Enable file hiding in any created file choosers * @param fileHiding Whether or not to hide files. Default is no. * @return this */ public FileChooserBuilder setFileHiding(boolean fileHiding) { this.fileHiding = fileHiding; return this; } /** * Show/hide control buttons * @param fileHiding Whether or not to hide files. Default is no. * @return this */ public FileChooserBuilder setControlButtonsAreShown(boolean val) { this.controlButtonsShown = val; return this; } /** * Enable file hiding in any created file choosers * @param fileHiding Whether or not to hide files. Default is no. * @return this */ public FileChooserBuilder setAccessibleDescription(String aDescription) { this.aDescription = aDescription; return this; } /** * Create a JFileChooser that conforms to the parameters set in this * builder. * @return A file chooser */ public JFileChooser createFileChooser() { JFileChooser result = new SavedDirFileChooser(dirKey, failoverDir, force); prepareFileChooser(result); return result; } private boolean force = false; /** * Force use of the failover directory - i.e. ignore the directory key * passed in. * @param val * @return */ public FileChooserBuilder forceUseOfDefaultWorkingDirectory(boolean val) { this.force = val; return this; } /** * Tries to find an appropriate component to parent the file chooser to * when showing a dialog. * @return */ private Component findDialogParent() { Component parent = KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner(); if (parent == null) { parent = KeyboardFocusManager.getCurrentKeyboardFocusManager().getActiveWindow(); } if (parent == null) { Frame[] f = Frame.getFrames(); parent = f.length == 0 ? null : f[f.length - 1]; } return parent; } /** * Show an open dialog that allows multiple selection. * @return An array of files, or null if the user cancelled the dialog */ public File[] showMultiOpenDialog() { JFileChooser chooser = createFileChooser(); chooser.setMultiSelectionEnabled(true); int result = chooser.showOpenDialog(findDialogParent()); if (JFileChooser.APPROVE_OPTION == result) { File[] files = chooser.getSelectedFiles(); return files == null ? new File[0] : files; } else { return null; } } /** * Show an open dialog with a file chooser set up according to the * parameters of this builder. * @return A file if the user clicks the accept button and a file or * folder was selected at the time the user clicked cancel. */ public File showOpenDialog() { JFileChooser chooser = createFileChooser(); chooser.setMultiSelectionEnabled(false); int dlgResult = chooser.showOpenDialog(findDialogParent()); if (JFileChooser.APPROVE_OPTION == dlgResult) { File result = chooser.getSelectedFile(); if (result != null && !result.exists()) { result = null; } return result; } else { return null; } } /** * Show a save dialog with the file chooser set up according to the * parameters of this builder. * @return A file if the user clicks the accept button and a file or * folder was selected at the time the user clicked cancel. */ public File showSaveDialog() { JFileChooser chooser = createFileChooser(); int result = chooser.showSaveDialog(findDialogParent()); if (JFileChooser.APPROVE_OPTION == result) { return chooser.getSelectedFile(); } else { return null; } } private void prepareFileChooser(JFileChooser chooser) { chooser.setFileSelectionMode(dirsOnly ? JFileChooser.DIRECTORIES_ONLY : filesOnly ? JFileChooser.FILES_ONLY : JFileChooser.FILES_AND_DIRECTORIES); chooser.setFileHidingEnabled(fileHiding); chooser.setControlButtonsAreShown(controlButtonsShown); if (title != null) { chooser.setDialogTitle(title); } if (approveText != null) { chooser.setApproveButtonText(approveText); } if (badger != null) { chooser.setFileView(new CustomFileView(new BadgeIconProvider(badger), chooser.getFileSystemView())); } if (preventSymlinkTraversal) { FileUtil.preventFileChooserSymlinkTraversal(chooser, chooser.getCurrentDirectory()); } if (filter != null) { chooser.setFileFilter(filter); } if (aDescription != null) { chooser.getAccessibleContext().setAccessibleDescription(aDescription); } } private static final class SavedDirFileChooser extends JFileChooser { private final String dirKey; SavedDirFileChooser(String dirKey, File failoverDir, boolean force) { this.dirKey = dirKey; if (force && failoverDir != null && failoverDir.exists() && failoverDir.isDirectory()) { setCurrentDirectory(failoverDir); } else { String path = NbPreferences.forModule(FileChooserBuilder.class).get(dirKey, null); if (path != null) { File f = new File(path); if (f.exists() && f.isDirectory()) { setCurrentDirectory(f); } else if (failoverDir != null) { setCurrentDirectory(failoverDir); } } } } @Override public int showOpenDialog(Component parent) throws HeadlessException { int result = super.showOpenDialog(parent); if (result == APPROVE_OPTION) { saveCurrentDir(); } return result; } @Override public int showSaveDialog(Component parent) throws HeadlessException { int result = super.showSaveDialog(parent); if (result == APPROVE_OPTION) { saveCurrentDir(); } return result; } private void saveCurrentDir() { File dir = super.getCurrentDirectory(); if (dir.exists() && dir.isDirectory()) { NbPreferences.forModule(FileChooserBuilder.class).put(dirKey, dirKey); } } } //Can open this API later if there is a use-case interface IconProvider { public Icon getIcon(File file, Icon orig); } /** * Provides "badges" for icons that indicate files or folders of particular * interest to the user. * @see FileChooserBuilder#setBadgeProvider */ public interface BadgeProvider { /** * Get the badge the passed file should use. Note: this method * is called for every visible file. The negative test (deciding * not to badge a file) should be very, very fast and immediately * return null. * @param file The file in question * @return an icon or null if no change to the appearance of the file * is needed */ public Icon getBadge(File file); /** * Get the x offset for badges produced by this provider. This is * the location of the badge icon relative to the real icon for the * file. * @return a rightward pixel offset */ public int getXOffset(); /** * Get the y offset for badges produced by this provider. This is * the location of the badge icon relative to the real icon for the * file. * @return a rightward pixel offset */ public int getYOffset(); } private static final class BadgeIconProvider implements IconProvider { private final BadgeProvider badger; public BadgeIconProvider(BadgeProvider badger) { this.badger = badger; } public Icon getIcon(File file, Icon orig) { Icon badge = badger.getBadge(file); if (badge != null && orig != null) { return new MergedIcon(orig, badge, badger.getXOffset(), badger.getYOffset()); } return orig; } } private static final class CustomFileView extends FileView { private final IconProvider provider; private final FileSystemView view; CustomFileView(IconProvider provider, FileSystemView view) { this.provider = provider; this.view = view; } @Override public Icon getIcon(File f) { Icon result = view.getSystemIcon(f); result = provider.getIcon(f, result); return result; } } private static class MergedIcon implements Icon { private Icon icon1; private Icon icon2; private int xMerge; private int yMerge; MergedIcon(Icon icon1, Icon icon2, int xMerge, int yMerge) { assert icon1 != null; assert icon2 != null; this.icon1 = icon1; this.icon2 = icon2; if (xMerge == -1) { xMerge = icon1.getIconWidth() - icon2.getIconWidth(); } if (yMerge == -1) { yMerge = icon1.getIconHeight() - icon2.getIconHeight(); } this.xMerge = xMerge; this.yMerge = yMerge; } public int getIconHeight() { return Math.max(icon1.getIconHeight(), yMerge + icon2.getIconHeight()); } public int getIconWidth() { return Math.max(icon1.getIconWidth(), yMerge + icon2.getIconWidth()); } public void paintIcon(java.awt.Component c, java.awt.Graphics g, int x, int y) { icon1.paintIcon(c, g, x, y); icon2.paintIcon(c, g, x + xMerge, y + yMerge); } } }