java.lang.IllegalArgumentException: input == null! when using ImageIO.read to load image as bufferedImage

Question

This is a question that has been asked like 100 times on this site, but I have looked at all of them and even though they all were solved, none of the solutions worked for m

Answer 1

Try using this:-

this.icon = ImageIO.read(new FileInputStream("res/test.txt"));

where res folder is present at the same level as your src folder. Also, if you notice, the slash / before the res folder name was removed.

Answer 2

I was facing this error due to a bug in my code. I was trying to extract (conn.getInputStream()) from a different connection object than what it should have been. I fixed the connection object variable and it started working.

BufferedImage image;
 try (InputStream in = new BufferedInputStream(conn.getInputStream())) {
   image = ImageIO.read(in);
   File file = new File(fullImageFilePath);
   synchronized (file.getCanonicalPath().intern()) {
     if (!file.exists()) {
         ImageIO.write(image, "png", file);
     }
   }
 }

Answer 3

Try this:

this.icon = ImageIO.read(this.getClass().getResource("/resources/" + imgName));

Answer 4

Try using the following

this.icon = ImageIO.read(this.getClass().getResourceAsStream("../resources/" + imgName));