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Java, display chm file loaded from resources in jar
(1 answer)
How do I determine the correct path for FXML files, CSS files, Images, and other resources needed by my JavaFX Application?
(1 answer)
Closed 1 year ago.
So I have created a java application in eclipse and I use javafx, and then exported it in a runnable jar file. However, when I run my .jar file it gives the error of not finding my images. It works perfectly fine when I run inside eclipse.
My file structure:
In UserPane I have a function that takes the image name as "title" and returns the imageview:
InputStream is=null;
try {
is=new FileInputStream("./Images/"+title+".jpg");
} catch (FileNotFoundException e) {
e.printStackTrace();
}
Image img=new Image(is);
ImageView imgview=new ImageView();
imgview.setImage(img);
imgview.setFitHeight(300);
imgview.setFitWidth(300);
return imgview;
I have tried some solutions, but it won't run in eclipse. I need it to run in eclipse and from the .jar.
I need it to be set in the imageview please.
Update: I did not use any of the suggestions mentioned because none of them were helpful, none of them worked. What worked for me is moving my .jar in the same folder where my images folder is, while still keeping the above code.
Thank you
FileInputStream is called that because it operates on files. In java, a file means exactly what it says: A file is a thing on a disk someplace.
An entry in a jar file is NOT ITSELF a file!
Therefore, when you write new FileInputStream? You lost the game. That can never work.
What you're looking for is a thing that lets you ask the JVM to give you resources from the same place the JVM is loading your class files.
Fortunately, that exists!
URL url = UserPane.class.getResource("/Images/" + title + ".png");
This gets you a url object, which you can pass to e.g. ImageIcon.
If you want to instead read it directly:
try (InputStream in = UserPane.class.getResourceAsStream("/Images/" + title + ".png")) {
// use 'in' here. It's `null` if the resource doesn't exist.
}
For this specific use case, you're looking for the URL variant. You don't need the InputStream at all.
Related
This question already has answers here:
java.io.FileNotFoundException: the system cannot find the file specified
(8 answers)
Closed 4 years ago.
I have a csv file in the same path as everything else. Now, when I try to create a File object:
public void getMenu() {
File fileMenu = new File("FastFoodMenu.csv");
try {
Scanner inputStream = new Scanner(fileMenu);
while (inputStream.hasNext()) {
String data = inputStream.next();
System.out.println(data);
}
} catch (FileNotFoundException ex) {
Logger.getLogger(FileHandler.class.getName()).log(Level.SEVERE, null, ex);
}
}
it throws a FileNotFoundException.
the absolute path to all files in the project is:
C:\Users\kenyo\Documents\NetBeansProjects\OrderFastFood\src\fastfoodorderingsystem
I also checked the name a couple of times. fileMenu.exists() returns false.
First, in your root/working directory (in your case it's the folder containing your project), create a folder called 'menus', here you can store all your menus (so you can play around with multi-file input).
Second, move your FastFoodMenu.csv file to that menus folder.
The FastFoodMenu.csv relative path should now look like this: OrderFastFood\menus\FastFoodMenu.csv.
Third, get your working directory from the System properties. This is the folder in which your program is working in. Then, get a reference (File object) to the menus folder.
Lastly, get a reference to the file in question inside the menu folder. When you get to multi-file reading (and at some point, multi-folder reading), you're gonna want to get the files inside the menu folder as a list so that's why I say to just get the menus folder as it's own reference (or just get the file without the isolated reference to the parent aka '\menus\').
So your code should really look like this:
public void getMenu() {
final File workingDir = File(System.getProperty("user.dir"));
final File menusDir = File(workingDir, "menus");
final File fastFoodMenu = File(menusDir, "FastFoodMenu.csv");
try {
final FileInputStream fis = new FileInputStream(fastFoodMenu);
final BufferedInputStream bs = new BufferedInputStream(fis);
while((l = bs.readLine()) != null) {
System.out.println(l);
}
} catch(FileNotFoundException e) {
System.out.println(e.getMessage());
e.printStackTrace()
}
}
This is all psuedocode but that should at least get you started. Make sure to use BufferedInputStream for efficiency, and when reading files, always pass them into FileInputStream's. It's much better than using the Scanner class. I should also mention that when creating a File object, you're not actually creating a file. What you're doing is your're creating an object, giving it the data you want it to have (such as whether it's a folder, and if it is, what child files/folders do you want it to have, whether it's protected or not, hidden or not, etc) before actually telling the system to create the file with everything else.
Your csv file is probably at the wrong place. You're just specifying the file name, which is a relative path.
Relative paths are always resolved against the working directory of your application, not against the directory where your source file(s) are.
To solve the issue, you can
move the files to the real working directory.
use an absolute path (not advisable!)
specify the folder of your data files as program argument or in a config file (in your working directory)
put the files somewhere into the classpath of your application and load them from there via classloader. Note that files that are in your classpath are usually packed with your application and hence not easily modifiable by the user, so this solution doesn't work if the file must be changed by the user.
I have a javafx project, which contains multiple paths for images and text files :
private Image imgMan = new Image(getClass().getResource("../man.gif").toExternalForm());
FileHelper.resetScores("./bin/application/MAP/BestScores.txt");
...
When i launch from eclipse, it work normally, and access to images and files without any problem.
But when i try to export my project to a jar file, it export correctly, but it don't launch !
I try to launch it from cmd, the trace of stack said that he don't know the paths...
Caused by: java.lang.NullPointerException
at application.Client.(Client.java:31)
(line 31 in my code refer to the first line of code given in the question)
I try to create a resource folder and put all files into it, but no result.
So what is the best way to make it ?
where must i create the resource folder ?
and how to access the files into it from the code ?
Thank you
There are several thing you should check:
verify the path in your jar against the class you are looking. Your image must be there.
verify you have successfully loaded a resource because using it, eg: check if getResource returns null.
For the first point, it depends on how you build your jar:
Eclipse will by default copy class file and resources to bin unless you use m2e. If you use the Extract runnable JAR (from File > Export menu), it may ignore some resources.
If you use Maven then your images must be in src/main/resources by default.
For the second point, you should use a method that should check the resource exists before delegating to Image. While it won't change your core problem, you would have a less subtile error:
static javafx.scene.image.Image loadImage(Class<?> source, String path) {
final InputStream is = source.getResourceAsStream(path);
if (null == is) {
throw new IllegalStateException("Could not load image from " + source + " path: " + path);
}
try (is) { // Java 9 -> you may want to use InputStream is2 = is
return new javafx.scene.image.Image(is); // use is2 for Java < 9
}
}
You should also try with an absolute path (from the root of the jar, or your src/main/resources if you use maven):
Image image = loadImage(this.getClass(), "/images/man.gif");
I've built a Java application that loads an image at runtime. The location of the image is fixed relative to the project.
I would like to be able to run the program from both within Eclipse and the command line and for it to load the image correctly. However, I can only do one or the other but not both. This seems like such a trivial thing to want to do but I can't find out how to do it.
The project is set up so that it creates a bin directory for the output and puts the image in a resources sub-folder. This is fine when running from the command line as I can write my code to look in that sub folder for the file.
But when I run the program from within eclipse the current working directory is different.
What am I missing?
TIA
Update - adding some code
This is what I had originally:
BufferedImage awtImage = ImageIO.read(new File(System.getProperty("user.dir") + "/resources/image-name.png"));
Following the advice in the comments I am trying to use getResourceAsStream but I don't know what to pass to the File constructor.
InputStream temp = MyClass.class.getResourceAsStream("resources/image-name.png");
BufferedImage awtImage = ImageIO.read(new File(???));
The resource is being found because temp is not null.
I think there's 2 solutions.
1) you specify an absolute path
2) your image is in the classpath so you could load it via :
YouClass.class.getResourceAsStream("YourImg.png");
The working directory, if that's really what you mean, is not a great place to load an image from. It appears that you have an image that you would distribute with your finished program so that the program could use it. In that case, I suggest that you use Class.getResourceAsStream(), and put the image in the directory with (or near) that class.
EDIT:
Here is code I used in one of my programs for a similar purpose:
ImageIcon expandedIcon = null;
// ...
expandedIcon = new ImageIcon(TreeIcon.class.getResource("images/Expanded.png"));
The ImageIcon class is part of Swing; I don't know if you're using that, but this should serve to show you the idea. The getResource() method takes a URL; again, you might need something a little different. But this shows the pathname relative to the path of the class on which the method is called, so if TreeIcon is in x/y/z/icons, the PNG file needs to be in x/y/z/icons/images, wherever that is on that computer.
TreeIcon is a class of mine, and its internals will not help you, so I'm not posting them. All it's doing here is providing a location for the PNG file I'm loading into an ImageIcon instance.
In addition to working on a disk with a directory structure, this also works in a jar file (which is a common way to distribute a java program or library). The jar file is just a zip file, and each file in the jar/zip file has its directory associated with it, so the image can be in the jar in the correct directory just as the java classes are in their directories.
getResourceAsStream() returns a stream; if you want to use that byte stream to load as an image, find a class that converts an stream to something your image class can use as a constructor or in a load method and hook them up. This is a common thing to have to figure out with Java i/o, unfortunately there is no cookbook way to do it across all images and situations, so we can't just tell you what it is.
EDIT 2:
As from the comment, try:
ImageIO.read(new File(MyClass.class.getResource("resources/image-name.png");
I set up my Eclipse projects like this.
The input directory is added to the classpath (JavaBuildPath in Eclipse).
Finally, you access the image and / or text files like this.
private BufferedImage getIconImage() {
try {
return ImageIO.read(getClass().getResourceAsStream(
"/StockMarket.png"));
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
This question already has answers here:
How do I read a resource file from a Java jar file?
(9 answers)
Closed 9 years ago.
I'm writing a game in java and all is working more or less well, as you would expect when coding, but one issue I have come across is reading the image and sound files into the game. I wrote a method that works really well within Eclipse, but as soon as I try to test it in a runnable jar (exported using Eclipse) my game gets stuck on the loading screen because it can't read the files. I realized the problem there being that you cannot create File objects within a Jar, you have to use streams. This could work, but the images/sounds are located within folders and I'm not very sure how you can read files within a folder with streams(i.e not knowing the amount of files). Because of this I have tried to rewrite the method using the ZipInputStream (I found this as recommended when looking for solutions prior to posting this). This is what the method looks like now:
imageMap = new HashMap<String, BufferedImage>();
String imagebase = "/images";
CodeSource src = PlatformerCanvas.class.getProtectionDomain().getCodeSource();
if(src != null)
{
URL jar = src.getLocation();
try
{
ZipArchiveInputStream zip = new ZipArchiveInputStream(jar.openStream());
ZipArchiveEntry ze = null;
while((ze = zip.getNextZipEntry()) != null)
{
System.out.println(ze.getName());
if(ze.getName().startsWith(imagebase) && ze.getName().endsWith(".png"))
{
loading++;
imageMap.put(ze.getName().replaceAll(imagebase + "/", ""), ImageIO.read(this.getClass().getResource(ze.getName())));
}
}
zip.close();
System.out.println("Finished Loading Images");
}
catch (IOException e)
{
e.printStackTrace();
}
}
However, this completely skips over the while loop because getNextZipEntry return null. I tried using the base Zip archive libraries, but someone recommended the Apache Commons libraries, but neither worked. My Jar setup is this:
Jar
/game/gameClasses
/images/imageFiles
/sounds/soundFiles
/whateverOtherFoldersEclipseCreated
So my question is this: Why isn't this current method working and how do I fix it? Or, how can I load the images/sounds in a different way that works?
I have looked at many other questions and tried many different things, but none worked for me.
Or, how can I load the images/sounds in a different way that works?
One common technique is to include a list of resources in a known location in the Jar. Read the list, then iterate the lines (presuming one line per resource) & read the paths that way.
Android seems to make life pretty easy for loading resources of certain types. Once I leave the beaten path a little bit, it seems less helpful. I can load in images, sounds and other objects from the assets folder if and only if they are of certain types. If I try to load a binary file of my own format, I get a less than helpful 'file not found' exception, even though listing the directory shows that it is clearly there.
I've tried using the following methods to read a binary file of a custom format from the assets directory:
File jfile = new File("file://android_asset/"+filename); //tried to get the URI of the assets folder
JarFile file = new JarFile("assets/"+filename); //tried assuming the assets folder is root
fd = am.openNonAssetFd( filename); //tried getting my file as an non asset in the assets folder (n.b. it is definitely there)
fs = am.open(filename, AssetManager.ACCESS_BUFFER); //tried loading it as an asset
I'm thinking that there's something fundamental about android file I/O that I don't understand yet. The documentation for asset management seems incomplete and there must be some reason for deliberately making this unintuitive (something to do with security?). So, what's the fool proof, canonical way of loading a binary file of my own format within an android app?
UPDATE:
I tried file:///android_asset/ but still no joy.
String fullfilename = "file:///android_asset/"+filename;
File jfile = new File(fullfilename);
if (jfile.exists())
{
return new FileInputStream(jfile);
}
else
{
return null; //the file does exist but it always says it doesn't.
}
Are there any permissions for the file or in the project manifest that I need?
Thanks
I think the best way to load a file from the Assets folder would be to use AssetManager.open(String filename) - this gives you back an InputStream which you can then wrap in a BufferedInputStream and otherwise call read() to get the bytes. This would work regardless of the file type. What kind of problems have you had with this approach specifically?
I think you have left out the slash as in
File jfile = new File("file:///android_asset/"+filename);
There's three forward slashes, not two. :)
For me the solution was to uninistall the application, clean the project in Eclipse and run it again. The problem was Android couldn't find the new files I put in the asset folder.
I ended up reading this question so I hope this can be helpful to someone else.