允许 Java 应用程序在录制音频时继续运行

Question

我正在尝试嵌入一些我找到的代码（原始 here），用于将音频输入录制和保存到 Java swing 应用程序中。我的问题是我希望录音运行与应用程序正在做的其他事情同时进行，但实际上，应用程序会暂停，直到录音完成。我怎样才能防止这种情况发生？

这是产生问题的我的代码的简化版本。显示"Now recording"的行直到录音完成后才出现。

import javax.sound.sampled.*;

import java.io.*;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.io.File;

import javafx.embed.swing.JFXPanel;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class Example extends JPanel {

    protected static final long serialVersionUID = 1L;

    // whether we've started recording
    private boolean startedRecording;

    // record duration, in milliseconds
    static final long RECORD_TIME = 5000;  // 5 seconds

    // format of audio file
    AudioFileFormat.Type fileType = AudioFileFormat.Type.WAVE;

    // path of the wav file
    File wavFile;

    // the line from which audio data is captured
    TargetDataLine line;

    public Example( String output_fn ) {
        wavFile = new File(output_fn);
        startedRecording = false;
        setPreferredSize(new Dimension(100,100));
        createPanel();
    }

    public static JFXPanel createPanel() {
        return new JFXPanel();
    }

    /**
     * Defines an audio format
     */
    AudioFormat getAudioFormat() {
        float sampleRate = 16000;
        int sampleSizeInBits = 8;
        int channels = 2;
        boolean signed = true;
        boolean bigEndian = true;
        AudioFormat format = new AudioFormat(sampleRate, sampleSizeInBits,
                                             channels, signed, bigEndian);
        return format;
    }

    /**
     * Captures the sound and record into a WAV file
     */
    public void start() {
        try {
            AudioFormat format = getAudioFormat();
            DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);

            // checks if system supports the data line
            if (!AudioSystem.isLineSupported(info)) {
                System.out.println("Line not supported");
                System.exit(0);
            }
            line = (TargetDataLine) AudioSystem.getLine(info);
            line.open(format);
            line.start();   // start capturing

            System.out.println("In utils.Recorder: Start capturing...");

            AudioInputStream ais = new AudioInputStream(line);

            System.out.println("In utils.Recorder: Start recording...");

            // start recording
            AudioSystem.write(ais, fileType, wavFile);

        } catch (LineUnavailableException ex) {
            ex.printStackTrace();
        } catch (IOException ioe) {
            ioe.printStackTrace();
        }
        repaint();
    }

    /**
     * Closes the target data line to finish capturing and recording
     */
    public void finish() {
        line.stop();
        line.close();
        System.out.println("In utils.Recorder: Finished");
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2   = (Graphics2D)g;
        // start recording
        if ( !startedRecording ) {
            startedRecording = true;
            Thread stopper = new Thread(new Runnable() {
                public void run() {
                    try {
                        Thread.sleep(RECORD_TIME);
                    } catch (InterruptedException ex) {
                        ex.printStackTrace();
                    }
                    Example.this.finish();
                }
            });
            stopper.start();
            this.start();
        }
        // display message
        g2.drawString("Now recording", 50, 50);
    }

    public static void main(String[] args) {
        final Example eg = new Example("TestRecordAudio.wav");
        JFrame f    = new JFrame();
        f.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
        f.add(eg, BorderLayout.CENTER);
        f.pack();
        f.setVisible(true);
        f.repaint();
    }
}

Answer 1

您正在 AWT Event Dispatch Thread 上调用 start 从而阻止任何其他事情发生。您需要在不同的线程上调用您的音频调用代码。

你永远不应该运行长时间运行 Swing 线程上的任务，除非你想面对死亡的灰色屏幕

Answer 2

画法是用来画画的！永远不要在 paint 方法中执行任何其他操作，这根本不合适，而且是一个非常非常糟糕的主意。

创建 JButton（或 JToggleButton）并将其用于 start/stop 录音。

使用line.stop()和line.close()停止录制。

Swing 是单线程环境，在事件调度线程上下文中执行的任何长运行或阻塞代码将阻止它处理事件队列，使它看起来像您的程序已挂起, 因为它有。

您可以使用 SwingWorker，但由于您在录制时不尝试更新 UI，因此使用 Thread[= 会更容易20=]

看看

了解更多详情

更新示例

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.IOException;
import javax.sound.sampled.AudioFileFormat;
import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioInputStream;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.TargetDataLine;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JToggleButton;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestRecord {

    public static void main(String[] args) {
        new TestRecord();
    }

    public TestRecord() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public static class TestPane extends JPanel {

        private JToggleButton recordButton;

        protected static final AudioFileFormat.Type FILE_TYPE = AudioFileFormat.Type.WAVE;
        private TargetDataLine line;

        public TestPane() {
            setLayout(new GridBagLayout());
            recordButton = new JToggleButton("Record");
            recordButton.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    if (recordButton.isSelected()) {
                        startRecording();
                        recordButton.setText("Stop");
                    } else {
                        stopRecording();
                        recordButton.setText("Record");
                    }
                }
            });
            add(recordButton);
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

        protected void stopRecording() {

            if (line != null) {

                line.stop();
                line.close();
                line = null;

            }

        }

        protected void startRecording() {
            if (line == null) {
                Thread t = new Thread(new Runnable() {

                    @Override
                    public void run() {
                        try {
                            AudioFormat format = getAudioFormat();
                            DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);

                            // checks if system supports the data line
                            if (!AudioSystem.isLineSupported(info)) {
                                System.out.println("Line not supported");
                                System.exit(0);
                            }
                            line = (TargetDataLine) AudioSystem.getLine(info);
                            line.open(format);
                            line.start();   // start capturing

                            System.out.println("In utils.Recorder: Start capturing...");

                            AudioInputStream ais = new AudioInputStream(line);

                            System.out.println("In utils.Recorder: Start recording...");

                            // start recording
                            System.out.println("Is recoding");
                            AudioSystem.write(ais, FILE_TYPE, new File("Test.wav"));

                        } catch (LineUnavailableException ex) {
                            ex.printStackTrace();
                        } catch (IOException ioe) {
                            ioe.printStackTrace();
                        }

                        System.out.println("Recording is done");
                    }
                });
                t.start();
            }
        }

        protected AudioFormat getAudioFormat() {
            float sampleRate = 16000;
            int sampleSizeInBits = 8;
            int channels = 2;
            boolean signed = true;
            boolean bigEndian = true;
            AudioFormat format = new AudioFormat(sampleRate, sampleSizeInBits,
                            channels, signed, bigEndian);
            return format;
        }
    }

}

（注意：我无法测试它，因为我没有可用的线路来支持录音......显然）

允许 Java 应用程序在录制音频时继续 运行

Allow Java application to continue running while recording audio

java

audio

swing

recording

允许 Java 应用程序在录制音频时继续运行