juke.java

用JAVA实现录音机功能

        if (currentSound instanceof Clip) {
            Clip clip = (Clip) currentSound;
            seconds = clip.getFramePosition() / clip.getFormat().getFrameRate();
        } else if ( (currentSound instanceof Sequence) || (currentSound instanceof BufferedInputStream) ) {
            try {
                seconds = sequencer.getMicrosecondPosition() / 1000000.0;
            } catch (IllegalStateException e){
                System.out.println("TEMP: IllegalStateException "+
                    "on sequencer.getMicrosecondPosition(): " + e);
            }
        }
        return seconds;
    }


    public void update(LineEvent event) {
        if (event.getType() == LineEvent.Type.STOP && !paused) { 
            audioEOM = true;
        }
    }


    public void meta(MetaMessage message) {
        if (message.getType() == 47) {  // 47 is end of track
            midiEOM = true;
        }
    }


    private void reportStatus(String msg) {
        if ((errStr = msg) != null) {
            System.out.println(errStr);
            playbackMonitor.repaint();
        }
        if (credits != null && credits.isAlive()) {
            credits.interrupt();
        }
    }


    public Thread getThread() {
        return thread;
    }


    public void start() {
        thread = new Thread(this);
        thread.setName("Juke");
        thread.start();
    }


    public void stop() {
        if (thread != null) {
            thread.interrupt();
        }
        thread = null;
    }


    public void run() {
        do {
            table.scrollRectToVisible(new Rectangle(0,0,1,1));
            for (; num < sounds.size() && thread != null; num++) {
                table.scrollRectToVisible(new Rectangle(0,(num+2)*(table.getRowHeight()+table.getRowMargin()),1,1));
                table.setRowSelectionInterval(num, num);
                if( loadSound(sounds.get(num)) == true ) {
                    playSound();
		}
                // take a little break between sounds
                try { thread.sleep(222); } catch (Exception e) {break;}
            }
            num = 0;
        } while (loopB.isSelected() && thread != null);

        if (thread != null) {
            startB.doClick();
        }
        thread = null;
        currentName = null;
        currentSound = null;
        playbackMonitor.repaint();
    }


    public void setPan() {

        int value = panSlider.getValue();

        if (currentSound instanceof Clip) {
            try {
                Clip clip = (Clip) currentSound;
                FloatControl panControl = 
                    (FloatControl) clip.getControl(FloatControl.Type.PAN);
                panControl.setValue(value/100.0f);
            } catch (Exception ex) {
                ex.printStackTrace();
            }
        } else if (currentSound instanceof Sequence || currentSound instanceof BufferedInputStream) {
            for (int i = 0; i < channels.length; i++) {                
				channels[i].controlChange(10, (int)(((double)value + 100.0) / 200.0 *  127.0));
            }										 
        }
    }


    public void setGain() {
        double value = gainSlider.getValue() / 100.0;

        if (currentSound instanceof Clip) {
            try {
                Clip clip = (Clip) currentSound;
                FloatControl gainControl = 
                  (FloatControl) clip.getControl(FloatControl.Type.MASTER_GAIN);
                float dB = (float) 
                  (Math.log(value==0.0?0.0001:value)/Math.log(10.0)*20.0);
                gainControl.setValue(dB);
            } catch (Exception ex) {
                ex.printStackTrace();
            }
        } else if (currentSound instanceof Sequence || currentSound instanceof BufferedInputStream) {
            for (int i = 0; i < channels.length; i++) {                
				channels[i].controlChange(7, (int)(value * 127.0));

			}
        }
    }



    /**
     * GUI controls for start, stop, previous, next, pan and gain.
     */
    class JukeControls extends JPanel implements ActionListener, ChangeListener {

        public JukeControls() {
            setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));

            JPanel p1 = new JPanel();
            p1.setLayout(new BoxLayout(p1, BoxLayout.Y_AXIS));
            p1.setBorder(new EmptyBorder(10,0,5,0));
            JPanel p2 = new JPanel();
            startB = addButton("Start", p2, sounds.size() != 0);
            pauseB = addButton("Pause", p2, false);
            p1.add(p2);
            JPanel p3 = new JPanel();
            prevB = addButton("<<", p3, false);
            nextB = addButton(">>", p3, false);
            p1.add(p3);
            add(p1);
    
            JPanel p4 = new JPanel(new BorderLayout());
            EmptyBorder eb = new EmptyBorder(5,20,10,20);
            BevelBorder bb = new BevelBorder(BevelBorder.LOWERED);
            p4.setBorder(new CompoundBorder(eb,bb));
            p4.add(playbackMonitor);
            seekSlider = new JSlider(JSlider.HORIZONTAL, 0, 100, 0);
            seekSlider.setEnabled(false);
            seekSlider.addChangeListener(this);
            p4.add("South", seekSlider);
            add(p4);

            JPanel p5 = new JPanel();
            p5.setLayout(new BoxLayout(p5, BoxLayout.X_AXIS));
            p5.setBorder(new EmptyBorder(5,5,10,5));
            panSlider = new JSlider(-100, 100, 0);
            panSlider.addChangeListener(this);
            TitledBorder tb = new TitledBorder(new EtchedBorder());
            tb.setTitle("Pan = 0.0");
            panSlider.setBorder(tb);
            p5.add(panSlider);
            gainSlider = new JSlider(0, 100, 80);
            gainSlider.addChangeListener(this);
            tb = new TitledBorder(new EtchedBorder());
            tb.setTitle("Gain = 80");
            gainSlider.setBorder(tb);
            p5.add(gainSlider);
            add(p5);
        }

        private JButton addButton(String name, JPanel panel, boolean state) {
            JButton b = new JButton(name);
            b.addActionListener(this);
            b.setEnabled(state);
            panel.add(b);
            return b;
        }

        public void stateChanged(ChangeEvent e) {
            JSlider slider = (JSlider) e.getSource();
            int value = slider.getValue();
            if (slider.equals(seekSlider)) {
                if (currentSound instanceof Clip) {
                    ((Clip) currentSound).setFramePosition(value);
                } else if (currentSound instanceof Sequence) {
                    long dur = ((Sequence) currentSound).getMicrosecondLength();
					sequencer.setMicrosecondPosition(value * 1000);
                } else if (currentSound instanceof BufferedInputStream) {
                    long dur = sequencer.getMicrosecondLength();
					sequencer.setMicrosecondPosition(value * 1000);
                }
                playbackMonitor.repaint();
                return;
            }
            TitledBorder tb = (TitledBorder) slider.getBorder();
            String s = tb.getTitle();
            if (s.startsWith("Pan")) {
                s = s.substring(0, s.indexOf('=')+1) + s.valueOf(value/100.0);
                if (currentSound != null) {
                    setPan();
                }
            } else if (s.startsWith("Gain")) {
                s = s.substring(0, s.indexOf('=')+1) + s.valueOf(value);
                if (currentSound != null) {
                    setGain();
                }
            } 
            tb.setTitle(s);
            slider.repaint();
        }


        public void setComponentsEnabled(boolean state) {
            seekSlider.setEnabled(state);
            pauseB.setEnabled(state);
            prevB.setEnabled(state);
            nextB.setEnabled(state);
        }



        public void actionPerformed(ActionEvent e) {
            JButton button = (JButton) e.getSource();
            if (button.getText().equals("Start")) {
                if (credits != null) {
                    credits.interrupt();
                }
                paused = false;
                num = table.getSelectedRow();
                num = num == -1 ? 0 : num;
                start();
                button.setText("Stop");
                setComponentsEnabled(true);
            } else if (button.getText().equals("Stop")) {
                credits = new Credits();
                credits.start();
                paused = false;
                stop();
                button.setText("Start");
                pauseB.setText("Pause");
                setComponentsEnabled(false);
            } else if (button.getText().equals("Pause")) {
                paused = true;
                if (currentSound instanceof Clip) {
                    ((Clip) currentSound).stop();
                } else if (currentSound instanceof Sequence || currentSound instanceof BufferedInputStream) {
                    sequencer.stop();
                }
                playbackMonitor.stop();
                pauseB.setText("Resume");
            } else if (button.getText().equals("Resume")) {
                paused = false;
                if (currentSound instanceof Clip) {
                    ((Clip) currentSound).start();
                } else if (currentSound instanceof Sequence || currentSound instanceof BufferedInputStream) {
                    sequencer.start();
                }
                playbackMonitor.start();
                pauseB.setText("Pause");
            } else if (button.getText().equals("<<")) {
                paused = false;
                pauseB.setText("Pause");
                num = num-1 < 0 ? sounds.size()-1 : num-2;
                bump = true;
            } else if (button.getText().equals(">>")) {
                paused = false;
                pauseB.setText("Pause");
                num = num+1 == sounds.size() ? -1 : num;
                bump = true;
            }
        }
    }  // End JukeControls



    /**
     * Displays current sound and time elapsed.
     */
    public class PlaybackMonitor extends JPanel implements Runnable {
        
        String welcomeStr = "Welcome to Java Sound";
        Thread pbThread;
        Color black = new Color(20, 20, 20); 
        Color jfcBlue = new Color(204, 204, 255);
        Color jfcDarkBlue = jfcBlue.darker();
        Font font24 = new Font("serif", Font.BOLD, 24);
        Font font28 = new Font("serif", Font.BOLD, 28);
        Font font42 = new Font("serif", Font.BOLD, 42);
        FontMetrics fm28, fm42;

        public PlaybackMonitor() {
            fm28 = getFontMetrics(font28);
            fm42 = getFontMetrics(font42);
        }
    
        public void paint(Graphics g) {
            Graphics2D g2 = (Graphics2D) g;
            Dimension d = getSize();
            g2.setBackground(black);
            g2.clearRect(0, 0, d.width, d.height);
            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
            g2.setColor(jfcBlue);

            if (errStr != null) {
                g2.setFont(new Font("serif", Font.BOLD, 18));
                g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF);
                g2.drawString("ERROR", 5, 20);
                AttributedString as = new AttributedString(errStr);
                Font font12 = new Font("serif", Font.PLAIN, 12);
                as.addAttribute(TextAttribute.FONT, font12, 0, errStr.length());
                AttributedCharacterIterator aci = as.getIterator();
                FontRenderContext frc = g2.getFontRenderContext();
                LineBreakMeasurer lbm = new LineBreakMeasurer(aci, frc);
                float x = 5, y = 25;
                lbm.setPosition(0);
                while (lbm.getPosition() < errStr.length()) {
                    TextLayout tl = lbm.nextLayout(d.width-x-5);
                    if (!tl.isLeftToRight()) {
                        x = d.width - tl.getAdvance();
                    }
                    tl.draw(g2, x, y += tl.getAscent());
                    y += tl.getDescent() + tl.getLeading();
                }
            } else if (currentName == null) {
                FontRenderContext frc = g2.getFontRenderContext();
                TextLayout tl = new TextLayout(welcomeStr, font28, frc);
                float x = (float) (d.width/2-tl.getBounds().getWidth()/2);
                tl.draw(g2, x, d.height/2);
                if (credits != null) {
                    credits.render(d, g2);
                }
            } else {