java - 我怎样才能从mysql获得blob并显示在jtextpane中？

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What is a NullPointerException, and how do I fix it?
                                
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我试图在jtextpane中显示来自mysql的图像，但不起作用，当我尝试将输入流转换为BufferedImage时出现问题，您能帮我吗？

private void initialize() {
    frame = new JFrame();
    frame.setBounds(100, 100, 508, 300);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.getContentPane().setLayout(null);

    JTextPane textPane = new JTextPane();
    textPane.setEditable(false);
    textPane.setBounds(55, 40, 370, 192);
    frame.getContentPane().add(textPane);

    try{
        Statement a = (Statement) con.createStatement();
        ResultSet b = a.executeQuery("Select imagen from chat");
        InputStream i = null;
        ImageIcon ii = null;
        if (b.next()) {
            i = b.getBinaryStream("imagen");
            BufferedImage bi = ImageIO.read(i);
            ii = new ImageIcon(bi);
            textPane.insertIcon(ii);
        }
    } catch ( SQLException | IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

控制台说...

java.lang.NullPointerException
at javax.swing.ImageIcon.<init>(Unknown Source)
at imagen.initialize(imagen.java:75)

我找不到解决方案

最佳答案

如果imagen.java文件的第75行上的元素可能为null，则会收到NullPointerException错误。 Go to solutuon

关于java - 我怎样才能从mysql获得blob并显示在jtextpane中？ ，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/44631047/