Images in JAR File (via Eclipse)

[AndrewM16921]

Hey, I'm using Eclipse. I've written the first portion of my latest program, which uses images in a source folder called "img". When I run it in Eclipse, the images show up fine. However, when I try to execute the JAR file they do not show up. Perhaps I'm having trouble understanding exactly how I'm suppose to export them.

I searched for help on sun's website ( New To Java - Re: How can I pack images into a runnable jar file in Eclipse? ), and tried to follow the help provided there. However, nothing I did seemed to work. Can someone try to explain what I need to do? Help appreciated.

[masijade]

Make sure that that directory actaully exists in the Jar and ensure that you are using getResource properly (and you won't be able to "File" in any way shape or form).

Edit: It would help if you posted the code used to "load" the images.

[AndrewM16921]

I don't know anything about getResource, so I assume that's my problem.

//Example Image use

import javax.swing.ImageIcon;

public class Grass extends AreaComponent
{
	public Grass()
	{
		super(
		new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), 
		new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), 
		false);
	}
}

Would this be the proper way to go about doing this?

//Example Image use

import javax.swing.ImageIcon;

public class Grass extends AreaComponent
{
	public Grass()
	{
		super(
		new ImageIcon(getResource("img\\AreaComponent\\Grass\\1.gif").getImage(),
		new ImageIcon(getResource("img\\AreaComponent\\Grass\\1.gif"))).getImage(),
		false);
	}
}

[masijade]

See How to Use Icons (The Java™ Tutorials > Creating a GUI With JFC/Swing > Using Swing Components)

[mrmatt1111]

To build upon what masijade mentioned about "getResource":

To understand where things are to your existing file path:

File file = new File(""); //this is currently where you are looking for your grass
System.out.println("[not going to find it here]: " + file.getAbsolutePath());
      
System.out.println("[were are getting closer]: " + this.getClass().getResource(""));

System.out.println("[perhaps here (is it not null)?]: " + this.getClass().getResource("img/AreaComponent/Grass/1.gif"));
System.out.println("[perhaps here (is it not null)?]: " + this.getClass().getResource("../img/AreaComponent/Grass/1.gif"));
      
//When you find the something that is non-null then:      
ImageIcon foundIt = new ImageIcon(this.getClass().getResource("img/AreaComponent/Grass/1.gif"));

[AndrewM16921]

I'm still immensely confused. For your code example, I kept getting null, even after I messed with it a bit based on the sun tutorial. Maybe if I post two of my classes (AreaComponent and Grass), someone can try to explain how to go about using getResource() properly. I've tried like 6 different implementations, each of which either gives me an error or a nullPointerException.

import javax.swing.ImageIcon;

public class Grass extends AreaComponent
{
	public Grass()
	{
		super(new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), false);
	}
}

import java.awt.Image;

public class AreaComponent
{
	private Image occupiedImage, unoccupiedImage;
	private boolean occupied, solid;
	
	public AreaComponent(Image occupiedImg, Image unoccupiedImg, boolean sol)
	{
		occupiedImage = occupiedImg;
		unoccupiedImage = unoccupiedImg;
		solid = sol;
	}
	
	/* Run this method if the player enters this space */
	public void playerEnter(Area area, Player player)
	{
		occupied = true;
	}
	
	/* Run this method if the player exits this space */
	public void playerExit(Area area, Player player)
	{
		occupied = false;
	}
	
	/* Returns altered Area when player enters */
	public Area areaActionPlayerEnter(Area area, Player player)
	{
		return area;
	}
	
	/* Returns altered Area when player exits */
	public Area areaActionPlayerExit(Area area, Player player)
	{
		return area;
	}
	
	/* Sets occupied to occupy */
	public void setOccupied(boolean occupy)
	{
		occupied = occupy;
	}
	
	/* Returns the appropriate Image */
	public Image getImage()
	{
		if(!occupied)
			return unoccupiedImage;
		else
			return occupiedImage;
	}
	
	/* Returns true if the AreaComponent is currently occupied, false otherwise */
	public boolean isOccupied()
	{
		return occupied;
	}
	
	/* Returns true if the AreaComponent is solid, false otherwise */
	public boolean isSolid()
	{
		return solid;
	}
}

[mrmatt1111]

What is displayed when you run this code?

import javax.swing.ImageIcon;

public class Grass extends AreaComponent
{
	public Grass()
	{
		//super(new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), false);
             super(null, null, false);
             javax.swing.JOptionPane.showMessageDialog(null, "" + this.getClass().getResource(""));
	}
}

[masijade]

Have you bothered reading that tutorial yet (probably not), there is a section dedicated to using getResource for loading the images. I don't post things for no reason.

[AndrewM16921]

Have you bothered reading that tutorial yet (probably not), there is a section dedicated to using getResource for loading the images. I don't post things for no reason.

I'm still immensely confused. For your code example, I kept getting null, even after I messed with it a bit based on the sun tutorial. Maybe if I post two of my classes (AreaComponent and Grass), someone can try to explain how to go about using getResource() properly. I've tried like 6 different implementations, each of which either gives me an error or a nullPointerException.

Yes, I did look at the tutorial. I didn't seem to understand it entirely, but I will look again.

What is displayed when you run this code?

import javax.swing.ImageIcon;

public class Grass extends AreaComponent
{
	public Grass()
	{
		//super(new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), new ImageIcon("img\\AreaComponent\\Grass\\1.gif").getImage(), false);
             super(null, null, false);
             javax.swing.JOptionPane.showMessageDialog(null, "" + this.getClass().getResource(""));
	}
}

It prints:
file:/F:/Workspace/DarkBrotherhood/bin/

[hr]

Now, I'm thinking something like
Grass.class.getResource("img\\AreaComponent\\Grass \\1.gif")
But I'm not sure exactly how to implement this.

[mrmatt1111]

Edit: Nevermind.

[AndrewM16921]

I actually figured out a way to do it without using getResource. Thanks for the help, anyway.

[Fubarable]

I actually figured out a way to do it without using getResource. Thanks for the help, anyway.

getResource is the proper solution here, so any "solution" that doesn't use it is possibly suspect. Please explain your solution, so we can make sure that you're not shooting yourself in the foot.

[masijade]

P.S. With getResource you use "/" not "\\", and, now, look at the following situation

Your jarfile has the following setup

package1
  package2
    YourClass.class
    img
      yourimage.gif

now from YourClass you use getResource as follows:

getResource("img/yourimage.gif")


now suppose your jarfile is setup as follows

package1
  package2
    YourClass.class
img
  yourimage.gif

Now getResource is as follows:

getResource("/img/yourimage.gif")


Do you see the difference in those? A leading "/" on the path in getResource means "start from the package root". If a leading "/" is not present it means "start from the current package".

Do you understand?

[AndrewM16921]

Yes, that makes sense, thank you. I will try that out as well.

As for my other solution, I simply put the img folder parallel to the jar file rather than inside of it. I would rather have it as a single jar file, so I will look into what you posted when I get a chance. Thanks. =)