如何将 javax.mail.Session setDebug 重定向到 jTextArea

Question

如何将 javax.mail.Session setDebug 重定向到 jTextArea？

ByteArrayOutputStream os = new ByteArrayOutputStream();
PrintStream ps = new PrintStream(os);
Session mailSession = Session.getDefaultInstance(props, null);
logger.info("JAVAMAIL debug mode is ON");
mailSession.setDebug(true);
mailSession.setDebugOut(ps);
logger.info(os);

Answer 1

您可以创建或找到 swing hander implementation 并将其附加到 JavaMail 使用的 javax.mail 记录器命名空间。
您可以使用线程和 piped I/O 读取调试输出并将其写入文本区域。

您可以创建在 'autoflush' 期间写入文本区域的缓冲输出流。

public class AreaDebug {

    public static void main(String[] args) throws Exception {
        EventQueue.invokeAndWait(new Runnable() {
            @Override
            public void run() {
                test();
            }
        });
    }

    private static void test() {
        assert EventQueue.isDispatchThread() : Thread.currentThread();
        final Session s = Session.getInstance(new Properties());
        JTextArea area = new JTextArea();
        Adaptor out = new Adaptor(area.getDocument());
        s.setDebugOut(new PrintStream(out, true)); //Default encoding?
        s.setDebug(true);
        System.out.println(area.getText());
    }

    private static class Adaptor extends ByteArrayOutputStream {

        private final Document d;

        Adaptor(final Document d) {
            this.d = d;
        }

        @Override
        public void flush() throws IOException {
            final String a;
            synchronized (this) {
                super.flush();
                a = super.toString(); //Default encoding?
                super.reset();
            }

            Updater u = new Updater(d, a);
            if (EventQueue.isDispatchThread()) {
                u.run();
            } else {
                try {
                    EventQueue.invokeAndWait(u);
                } catch (InterruptedException ex) {
                    Thread.currentThread().interrupt();
                    throw new InterruptedIOException();
                } catch (InvocationTargetException ex) {
                    throw new IOException(ex);
                }
            }
        }
    }

    private static class Updater implements Runnable {

        private final Document d;
        private final String append;

        Updater(Document d, String append) {
            this.d = d;
            this.append = append;
        }

        @Override
        public void run() {
            try {
                d.insertString(d.getLength(), append, (AttributeSet) null);
            } catch (BadLocationException ex) {
                Toolkit.getDefaultToolkit().beep();
            }
        }
    }
}

Answer 2

您可以使用 CustomOutputStream class http://www.codejava.net/java-se/swing/redirect-standard-output-streams-to-jtextarea 中描述的漂亮 CustomOutputStream:

import java.io.*;
import java.util.Properties;
import javax.mail.Session;
import javax.swing.*;

public class PrintStream2TextArea {
    public static void main(final String[] arguments) {
        new PrintStream2TextArea().launchGui();
    }

    private void launchGui() {
        final JFrame frame = new JFrame("Stack Overflow");
        frame.setBounds(100, 100, 800, 600);
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        final JTextArea textArea = new JTextArea(42, 28);
        setupMailSession(new Properties(), textArea);
        frame.getContentPane().add(textArea);
        frame.setVisible(true);
    }

    private void setupMailSession(final Properties props, final JTextArea textArea) {
        PrintStream ps = new PrintStream(new CustomOutputStream(textArea));
        Session mailSession = Session.getDefaultInstance(props, null);
        //logger.info("JAVAMAIL debug mode is ON");
        mailSession.setDebug(true);
        mailSession.setDebugOut(ps);
        //logger.info(os);
    }

    /**
     * This class extends from OutputStream to redirect output to a JTextArea.
     *
     * @author www.codejava.net
     */
    public static class CustomOutputStream extends OutputStream {
        private JTextArea textArea;

        public CustomOutputStream(JTextArea textArea) {
            this.textArea = textArea;
        }

        @Override
        public void write(int b) throws IOException {
            // redirects data to the text area
            textArea.append(String.valueOf((char)b));
            // scrolls the text area to the end of data
            textArea.setCaretPosition(textArea.getDocument().getLength());
        }
    }
}

如何将 javax.mail.Session setDebug 重定向到 jTextArea

How to redirect javax.mail.Session setDebug to jTextArea

swing

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