JFileChooser 图像到缓冲图像

Question

我在运行我的程序时遇到了一些问题。基本上我的程序的第 1 步是使用 JFileChooser 打开图像并将其制成缓冲图像，够简单吧？这就是我所拥有的：

JButton open = new JButton();
            JFileChooser fc = new JFileChooser();
            File selectedFile = fc.getSelectedFile();
            fc.setDialogTitle("Please choose an image...");
            FileNameExtensionFilter filter = new FileNameExtensionFilter("JPEG", "jpeg", "jpg", "png", "bmp", "gif");
            BufferedImage origImage = null;

            String path = "";
            File f = fc.getSelectedFile();
            boolean exists = false;
            fc.addChoosableFileFilter(filter);


            try {

                f = fc.getSelectedFile();
                exists = f.exists();
                path = f.getAbsolutePath();

                origImage = ImageIO.read(new File(path));
            }
            catch(Exception e) {
                System.out.println(e);
                System.exit(0);
            }

我得到一个空指针异常（由我的 catch 语句捕获）我认为它与 getbsolutepath 有关，但我不确定。有任何想法吗？谢谢！

Answer 1

您似乎从未真正打开文件选择器，因此没有选择任何文件会导致NullPointerException

JFileChooser fc = new JFileChooser();
fc.setDialogTitle("Please choose an image...");
FileNameExtensionFilter filter = new FileNameExtensionFilter("JPEG", "jpeg", "jpg", "png", "bmp", "gif");
fc.addChoosableFileFilter(filter);

BufferedImage origImage = null;
// You should use the parent component instead of null
// but it was impossible to tell from the code snippet what that was.
if (fc.showOpenDialog(null) == JFileChooser.APPROVE_OPTION) {
    File selectedFile = fc.getSelectedFile();
    try {
        origImage = ImageIO.read(selectedFile);
    } catch (IOException ex) {
        ex.printStackTrace();
    }
}

查看How to Use File Choosers了解更多详情

Answer 2

试试这个

path = f.getAbsolutePath().replace("\", "\\");