Develop Reference

JFileChooser - open in current directory

I have a simple JFileChooser set up in the following manner
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("."));
chooser.setFileSelectionMode(JFileChooser.FILES_AND_DIRECTORIES);
chooser.setFileFilter(new FileFilter() {
...
});
int v = chooser.showOpenDialog(this);
if (v == JFileChooser.APPROVE_OPTION) {
File file = chooser.getSelectedFile();
System.out.println(file.getAbsolutePath());
}
As you can see, this FileChooser starts out in the current directory, which in my Netbeans project, is the root of the project folder. Here's the problem: When I select a file and it prints out the absolute path, it includes the "." in the path. For instance, the output I get is:
/Users/MyName/Folder1/Folder2/./Temp.xls
Of course, this is weird, especially since I'm displaying this to the user. Now, I could be hacky and do some fun post substring processing stuff to get rid of that "/./" portion. But...is there a non-lazy programmer way to fix this problem? Thanks in advance!

Use the system property "user.dir" as follows:
File workingDirectory = new File(System.getProperty("user.dir"));
chooser.setCurrentDirectory(workingDirectory);

opening a javafx FileChooser in the user directory

I am trying to open a javafx FileChooser in the user directory according to an example I found here.
Here is a fragment of the simple code I am using:
FileChooser fc = new FileChooser();
fc.setTitle("Open Dialog");
String currentDir = System.getProperty("user.dir") + File.separator;
file = new File(currentDir);
fc.setInitialDirectory(file);
However, I keep obtaining this warning (complete file paths have been truncated):
Invalid URL passed to an open/save panel: '/Users/my_user'. Using 'file://localhost/Users/my_user/<etc>/' instead.
I verified that the file object is an existing directory adding these lines:
System.out.println(file.exists()); //true
System.out.println(file.isDirectory()); //true
Then I do not have idea why I am obtaining the warning message.
UPDATE:
This seems to be a bug in JavaFX: https://bugs.openjdk.java.net/browse/JDK-8098160
(you need to create a free Jira account to see the bug report).
This problem happens in OSX, no idea about other platforms.

This is what I ended up doing and it worked like a charm.
Also, make sure your folder is accessible when trying to read it (good practice). You could create the file and then check if you can read it. Full code would then look like this, defaulting to c: drive if you can't access user directory.
FileChooser fileChooser = new FileChooser();
//Extention filter
FileChooser.ExtensionFilter extentionFilter = new FileChooser.ExtensionFilter("CSV files (*.csv)", "*.csv");
fileChooser.getExtensionFilters().add(extentionFilter);
//Set to user directory or go to default if cannot access
String userDirectoryString = System.getProperty("user.home");
File userDirectory = new File(userDirectoryString);
if(!userDirectory.canRead()) {
userDirectory = new File("c:/");
}
fileChooser.setInitialDirectory(userDirectory);
//Choose the file
File chosenFile = fileChooser.showOpenDialog(null);
//Make sure a file was selected, if not return default
String path;
if(chosenFile != null) {
path = chosenFile.getPath();
} else {
//default return value
path = null;
}
This works on Windows and Linux, but might be different on other operating systems (not tested)

Try:
String currentDir = System.getProperty("user.home");
file = new File(currentDir);
fc.setInitialDirectory(file);

#FXML private Label label1; //total file path print
#FXML private Label labelFirst; //file dir path print
private String firstPath; //dir path save
public void method() {
FileChooser fileChooser = new FileChooser();
if (firstPath != null) {
File path = new File(firstPath);
fileChooser.initialDirectoryProperty().set(path);
}
fileChooser.getExtensionFilters().addAll(
new ExtensionFilter("Text Files", "*.txt"),
new ExtensionFilter("Image Files", "*.png", "*.jpg", "*.gif"),
new ExtensionFilter("Audio Files", "*.wav", "*.mp3", "*.aac"),
new ExtensionFilter("All Files", "*.*") );
File selectFile = fileChooser.showOpenDialog(OwnStage);
if (selectFile != null){
String path = selectFile.getPath();
int len = path.lastIndexOf("/"); //no detec return -1
if (len == -1) {
len = path.lastIndexOf("\\");
}
firstPath = path.substring(0, len);
labelFirst.setText("file path : " + firstPath);
label1.setText("First File Select: " + path);
}
}

Eclipse code runs fine, jar not

I'm new here and kinda new to java.
I've encountered a problem.
I have a very simple program that tries to create pngs and save them in a user selected folder.
byteimage is a a private byte[]:
byteimage = bcd.createPNG(300, 140, ColorSpace.TYPE_RGB, Color.BLACK, Color.BLACK);
setPath() is called inside the action listener of the browse button
private void setPath() {
JFileChooser pathchooser = new JFileChooser();
pathchooser.setMultiSelectionEnabled(false);
pathchooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
pathchooser.setApproveButtonMnemonic(KeyEvent.VK_ENTER);
pathchooser.showDialog(this, "OK");
File f = pathchooser.getSelectedFile();
if (f != null) {
filepath = f.getAbsolutePath();
pathfield.setText(filepath);
}
}
Byte to png method looks like this:
public void byteToPNG(String filename) {
try {
InputStream in = new ByteArrayInputStream(byteimage);
BufferedImage bufferedimg = ImageIO.read(in);
ImageIO.write(bufferedimg, "png", new File(filename));
} catch (IOException e) {
System.out.println(e.getMessage());
}
}
This method is called like this:
byteToPNG(pathfield.getText() + System.getProperty("file.separator") + textfield.getText() + ".png");
textfield.getText() sets the actual name of the png.
Inside the constructor, default filepath is set:
filepath = System.getProperty("user.dir");
pathfield.setText(filepath);
The code runs fine from Eclipse and it produces a png image at the desired location.
Unfortunately, after exporting as jar, it starts but when the button for generating the png is pressed, nothing happens. I'm thinking there's a problem at InputStream or BufferedImage, but I'm a bit puzzled.

If the String fileName passed to byteToPNG isn't absolute (i.e. written in the form "C:/foo/bar/etc") that could be the cause of the broken jar. You could also try running the jar file in the terminal using the command:
java -jar myJarFile.jar.
This will cause a console window to remain open alongside your running jar application in which all your applications output (including any exceptions) will be printed.

Modification to JFileChooser to just display folder content

i m trying to develop an gui application which display tree of filesystem on left side and on right side it display selected tree nodes (folder)'s content .
can any body tell me to do modification in jfilechooser to just to display folder content
thank you in advance

The JFileChooser#accept allows you to filter which files are displayed. A similar method is the JFileChooser#setFileFilter method

See: example
JFileChooser fileChooser = new JFileChooser();
fileChooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);

Perhaps this is what you expected:-
JFileChooser chooser = new JFileChooser();
chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
try {
// Create a File object containing the canonical path of the desired directory
File f = new File(new File(".").getCanonicalPath());
// Set the current directory
chooser.setCurrentDirectory(f);
} catch (IOException e1) {
e1.printStackTrace();
}
// Show the dialog; wait until dialog is closed
int returnVal = chooser.showOpenDialog(frame);
if(returnVal == JFileChooser.APPROVE_OPTION)
{
File f = chooser.getSelectedFile();
textField.setText(f.getAbsolutePath());
File[] contents = f.listFiles();
for(int file=0;file<contents.length;file++)
{
System.out.println(contents[file].getName()); //here you get the contents of the selected directory
}
}

Java - FileDialog Questions/Assistance

I am sure these are very nooby questions... But I have never had to deal with FileDialog before and I can't seem to get my coding to work.
This is my listener for my JButton, which I know it enters because a FileDialog pops up:
public static class FileListener implements ActionListener{
public void actionPerformed(ActionEvent e) {
FileDialog fd = new FileDialog(new Frame(), "Pick Folder");
String dir = "C:/";
fd.setDirectory(dir);
fd.setAlwaysOnTop(true);
fd.setMode(FileDialog.LOAD);
fd.setVisible(true);
String pickedFileDir = fd.getFile();
File folder = new File(pickedFileDir);
File[] listOfFiles = folder.listFiles();
numOfFiles = listOfFiles.length;
}
}
The problem is that I want it to be able to load a FOLDER. I need to get a directory out of it. And even when I do click on 1 file and press "Open" the numOfFiles doesn't change. I know this because of this code:
JLabel number = new JLabel("Files found: " + numOfFiles);
The label doesn't change after opening a file. It should go from "0" to "1".
Much appreciated if you can help me figure this out (obviously a "Best Answer" in there for ya :) )

You should use JFileChooser instead. Here is your example:
JFileChooser jfc = new JFileChooser();
jfc.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
jfc.setCurrentDirectory(new File("C:/"));
if (jfc.showOpenDialog(null) == JFileChooser.APPROVE_OPTION) {
File selectedFile = jfc.getSelectedFile();
File[] listOfFiles = selectedFile.listFiles();
}