SUN的经典JAVA钢琴程序 1

SUN的经典JAVA钢琴程序 1

package xiyou.wangbo;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.table.*;
import javax.swing.event.*;
import javax.sound.midi.*;
import java.util.Vector;
import java.io.File;
import java.io.IOException;

public class MidiSynth extends JPanel implements ControlContext {
    final int PROGRAM = 192;
    final int NOTEON = 144;
    final int NOTEOFF = 128;
    final int SUSTAIN = 64;
    final int REVERB = 91;
    final int ON = 0, OFF = 1;
    final Color jfcBlue = new Color(204, 204, 255);
    final Color pink = new Color(255, 175, 175);
    Sequencer sequencer;
    Sequence sequence;
    Synthesizer synthesizer;
    Instrument instruments[];
    ChannelData channels[];
    ChannelData cc;    // current channel
    JCheckBox mouseOverCB = new JCheckBox("mouseOver", true);
    JSlider veloS, presS, bendS, revbS;
    JCheckBox soloCB, monoCB, muteCB, sustCB;
    Vector keys = new Vector();
    Vector whiteKeys = new Vector();
    JTable table;
    Piano piano;
    boolean record;
    Track track;
    long startTime;
    RecordFrame recordFrame;
    Controls controls;

    public MidiSynth() {
        setLayout(new BorderLayout());
        JPanel p = new JPanel();
        p.setLayout(new BoxLayout(p, BoxLayout.Y_AXIS));
        EmptyBorder eb = new EmptyBorder(5,5,5,5);
        BevelBorder bb = new BevelBorder(BevelBorder.LOWERED);
        CompoundBorder cb = new CompoundBorder(eb,bb);
        p.setBorder(new CompoundBorder(cb,eb));
        JPanel pp = new JPanel(new BorderLayout());
        pp.setBorder(new EmptyBorder(10,20,10,5));
        pp.add(piano = new Piano());
        p.add(pp);
        p.add(controls = new Controls());
        p.add(new InstrumentsTable());
        add(p);
    }

    public void open() {
        try {
            if (synthesizer == null) {
                if ((synthesizer = MidiSystem.getSynthesizer()) == null) {
                    System.out.println("getSynthesizer() failed!");
                    return;
                }
            }
            synthesizer.open();
            sequencer = MidiSystem.getSequencer();
            sequence = new Sequence(Sequence.PPQ, 10);
        } catch (Exception ex) { ex.printStackTrace(); return; }
        Soundbank sb = synthesizer.getDefaultSoundbank();
if (sb != null) {
            instruments = synthesizer.getDefaultSoundbank().getInstruments();
            synthesizer.loadInstrument(instruments[0]);
        }
        MidiChannel midiChannels[] = synthesizer.getChannels();
        channels = new ChannelData[midiChannels.length];
        for (int i = 0; i < channels.length; i++) {
            channels = new ChannelData(midiChannels, i);
        }
        cc = channels[0];
        ListSelectionModel lsm = table.getSelectionModel();
        lsm.setSelectionInterval(0,0);
        lsm = table.getColumnModel().getSelectionModel();
        lsm.setSelectionInterval(0,0);
    }

    public void close() {
        if (synthesizer != null) {
            synthesizer.close();
        }
        if (sequencer != null) {
            sequencer.close();
        }
        sequencer = null;
        synthesizer = null;
        instruments = null;
        channels = null;
        if (recordFrame != null) {
            recordFrame.dispose();
            recordFrame = null;
        }
    }

    /**
     * given 120 bpm:
     *   (120 bpm) / (60 seconds per minute) = 2 beats per second
     *   2 / 1000 beats per millisecond
     *   (2 * resolution) ticks per second
     *   (2 * resolution)/1000 ticks per millisecond, or
     *      (resolution / 500) ticks per millisecond
     *   ticks = milliseconds * resolution / 500
     */
    public void createShortEvent(int type, int num) {
        ShortMessage message = new ShortMessage();
        try {
            long millis = System.currentTimeMillis() - startTime;
            long tick = millis * sequence.getResolution() / 500;
            message.setMessage(type+cc.num, num, cc.velocity);
            MidiEvent event = new MidiEvent(message, tick);
            track.add(event);
        } catch (Exception ex) { ex.printStackTrace(); }
    }

    /**
     * Black and white keys or notes on the piano.
     */
    class Key extends Rectangle {
        int noteState = OFF;
        int kNum;
        public Key(int x, int y, int width, int height, int num) {
            super(x, y, width, height);
            kNum = num;
        }
        public boolean isNoteOn() {
            return noteState == ON;
        }
        public void on() {
            setNoteState(ON);
            cc.channel.noteOn(kNum, cc.velocity);
            if (record) {
                createShortEvent(NOTEON, kNum);
            }
        }
        public void off() {
            setNoteState(OFF);
            cc.channel.noteOff(kNum, cc.velocity);
            if (record) {
                createShortEvent(NOTEOFF, kNum);
            }
        }
        public void setNoteState(int state) {
            noteState = state;
        }
    } // End class Key

    /**
     * Piano renders black & white keys and plays the notes for a MIDI
     * channel. 
     */
    class Piano extends JPanel implements MouseListener {
        Vector blackKeys = new Vector();
        Key prevKey;
        final int kw = 16, kh = 80;

        public Piano() {
            setLayout(new BorderLayout());
            setPreferredSize(new Dimension(42*kw, kh+1));
            int transpose = 24; 
            int whiteIDs[] = { 0, 2, 4, 5, 7, 9, 11 };
         
            for (int i = 0, x = 0; i < 6; i++) {
                for (int j = 0; j < 7; j++, x += kw) {
                    int keyNum = i * 12 + whiteIDs[j] + transpose;
                    whiteKeys.add(new Key(x, 0, kw, kh, keyNum));
                }
            }
            for (int i = 0, x = 0; i < 6; i++, x += kw) {
                int keyNum = i * 12 + transpose;
                blackKeys.add(new Key((x += kw)-4, 0, kw/2, kh/2, keyNum+1));
                blackKeys.add(new Key((x += kw)-4, 0, kw/2, kh/2, keyNum+3));
                x += kw;
                blackKeys.add(new Key((x += kw)-4, 0, kw/2, kh/2, keyNum+6));
                blackKeys.add(new Key((x += kw)-4, 0, kw/2, kh/2, keyNum+8));
                blackKeys.add(new Key((x += kw)-4, 0, kw/2, kh/2, keyNum+10));
            }
            keys.addAll(blackKeys);
            keys.addAll(whiteKeys);
            addMouseMotionListener(new MouseMotionAdapter() {
                public void mouseMoved(MouseEvent e) {
                    if (mouseOverCB.isSelected()) {
                        Key key = getKey(e.getPoint());
                        if (prevKey != null && prevKey != key) {
                            prevKey.off();
                        }
                        if (key != null && prevKey != key) {
                            key.on();
                        }
                        prevKey = key;
                        repaint();
                    }
                }
            });
            addMouseListener(this);
        }
        public void mousePressed(MouseEvent e) {
            prevKey = getKey(e.getPoint());
            if (prevKey != null) {
                prevKey.on();
                repaint();
            }
        }
        public void mouseReleased(MouseEvent e) {
            if (prevKey != null) {
                prevKey.off();
                repaint();
            }
        }
        public void mouseExited(MouseEvent e) {
            if (prevKey != null) {
                prevKey.off();
                repaint();
                prevKey = null;
            }
        }
        public void mouseClicked(MouseEvent e) { }
        public void mouseEntered(MouseEvent e) { }

        public Key getKey(Point point) {
            for (int i = 0; i < keys.size(); i++) {
                if (((Key) keys.get(i)).contains(point)) {
                    return (Key) keys.get(i);
                }
            }
            return null;
        }
        public void paint(Graphics g) {
            Graphics2D g2 = (Graphics2D) g;
            Dimension d = getSize();
            g2.setBackground(getBackground());
            g2.clearRect(0, 0, d.width, d.height);
            g2.setColor(Color.white);
            g2.fillRect(0, 0, 42*kw, kh);
            for (int i = 0; i < whiteKeys.size(); i++) {
                Key key = (Key) whiteKeys.get(i);
                if (key.isNoteOn()) {
                    g2.setColor(record ? pink : jfcBlue);
                    g2.fill(key);
                }
                g2.setColor(Color.black);
                g2.draw(key);
            }
            for (int i = 0; i < blackKeys.size(); i++) {
                Key key = (Key) blackKeys.get(i);
                if (key.isNoteOn()) {
                    g2.setColor(record ? pink : jfcBlue);
                    g2.fill(key);
                    g2.setColor(Color.black);
                    g2.draw(key);
                } else {
                    g2.setColor(Color.black);
                    g2.fill(key);
                }
            }
        }
    } // End class Piano

    /**
     * Stores MidiChannel information.
     */
    class ChannelData {
        MidiChannel channel;
        boolean solo, mono, mute, sustain;
        int velocity, pressure, bend, reverb;
        int row, col, num;

        public ChannelData(MidiChannel channel, int num) {
            this.channel = channel;
            this.num = num;
            velocity = pressure = bend = reverb = 64;
        }
        public void setComponentStates() {
            table.setRowSelectionInterval(row, row);
            table.setColumnSelectionInterval(col, col);
            soloCB.setSelected(solo);
            monoCB.setSelected(mono);
            muteCB.setSelected(mute);
            //sustCB.setSelected(sustain);
            JSlider slider[] = { veloS, presS, bendS, revbS };
            int v[] = { velocity, pressure, bend, reverb };
            for (int i = 0; i < slider.length; i++) {
                TitledBorder tb = (TitledBorder) slider.getBorder();
                String s = tb.getTitle();
                tb.setTitle(s.substring(0, s.indexOf('=')+1)+s.valueOf(v));
                slider.repaint();
            }
        }
    } // End class ChannelData

    /**
     * Table for 128 general MIDI melody instuments.
     */
    class InstrumentsTable extends JPanel {
        private String names[] = {
           "Piano", "Chromatic Perc.", "Organ", "Guitar",
           "Bass", "Strings", "Ensemble", "Brass",
           "Reed", "Pipe", "Synth Lead", "Synth Pad",
           "Synth Effects", "Ethnic", "Percussive", "Sound Effects" };
        private int nRows = 8;
        private int nCols = names.length; // just show 128 instruments
        public InstrumentsTable() {
            setLayout(new BorderLayout());
            TableModel dataModel = new AbstractTableModel() {
                public int getColumnCount() { return nCols; }
                public int getRowCount() { return nRows;}
                public Object getValueAt(int r, int c) {
                    if (instruments != null) {
                        return instruments[c*nRows+r].getName();
                    } else {
                        return Integer.toString(c*nRows+r);
                    }
                }
                public String getColumnName(int c) {
                    return names[c];
                }
                public Class getColumnClass(int c) {
                    return getValueAt(0, c).getClass();
                }
                public boolean isCellEditable(int r, int c) {return false;}
                public void setValueAt(Object obj, int r, int c) {}
            };
   
            table = new JTable(dataModel);
            table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
            // Listener for row changes
            ListSelectionModel lsm = table.getSelectionModel();
            lsm.addListSelectionListener(new ListSelectionListener() {
                public void valueChanged(ListSelectionEvent e) {
                    ListSelectionModel sm = (ListSelectionModel) e.getSource();
                    if (!sm.isSelectionEmpty()) {
                        cc.row = sm.getMinSelectionIndex();
                    }
                    programChange(cc.col*nRows+cc.row);
                }
            });
            // Listener for column changes
            lsm = table.getColumnModel().getSelectionModel();
            lsm.addListSelectionListener(new ListSelectionListener() {
                public void valueChanged(ListSelectionEvent e) {
                    ListSelectionModel sm = (ListSelectionModel) e.getSource();
                    if (!sm.isSelectionEmpty()) {
                        cc.col = sm.getMinSelectionIndex();
                    }
                    programChange(cc.col*nRows+cc.row);
                }
            });
            table.setPreferredScrollableViewportSize(new Dimension(nCols*110, 200));
            table.setCellSelectionEnabled(true);
            table.setColumnSelectionAllowed(true);
            for (int i = 0; i < names.length; i++) {
                TableColumn column = table.getColumn(names);
                column.setPreferredWidth(110);
            }
            table.setAutoResizeMode(table.AUTO_RESIZE_OFF);
       
            JScrollPane sp = new JScrollPane(table);
            sp.setVerticalScrollBarPolicy(sp.VERTICAL_SCROLLBAR_NEVER);
            sp.setHorizontalScrollBarPolicy(sp.HORIZONTAL_SCROLLBAR_ALWAYS);
            add(sp);
        }
        public Dimension getPreferredSize() {
            return new Dimension(800,170);
        }
        public Dimension getMaximumSize() {
            return new Dimension(800,170);
        }
        private void programChange(int program) {
            if (instruments != null) {
                synthesizer.loadInstrument(instruments[program]);
            }
            cc.channel.programChange(program);
            if (record) {
                createShortEvent(PROGRAM, program);
            }
        }
    }

    /**
     * A collection of MIDI controllers.
     */
    class Controls extends JPanel implements ActionListener, ChangeListener, ItemListener {
        public JButton recordB;
        JMenu menu;
        int fileNum = 0;
        public Controls() {
            setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
            setBorder(new EmptyBorder(5,10,5,10));
            JPanel p = new JPanel();
            p.setLayout(new BoxLayout(p, BoxLayout.X_AXIS));
            veloS = createSlider("Velocity", p);
            presS = createSlider("Pressure", p);
            revbS = createSlider("Reverb", p);
   // create a slider with a 14-bit range of values for pitch-bend
            bendS = create14BitSlider("Bend", p);
            p.add(Box.createHorizontalStrut(10));
            add(p);
            p = new JPanel();
            p.setBorder(new EmptyBorder(10,0,10,0));
            p.setLayout(new BoxLayout(p, BoxLayout.X_AXIS));
            JComboBox combo = new JComboBox();
            combo.setPreferredSize(new Dimension(120,25));
            combo.setMaximumSize(new Dimension(120,25));
            for (int i = 1; i <= 16; i++) {
                combo.addItem("Channel " + String.valueOf(i));
            }
            combo.addItemListener(this);
            p.add(combo);
            p.add(Box.createHorizontalStrut(20));
            muteCB = createCheckBox("Mute", p);
            soloCB = createCheckBox("Solo", p);
            monoCB = createCheckBox("Mono", p);
            //sustCB = createCheckBox("Sustain", p);
            createButton("All Notes Off", p);
            p.add(Box.createHorizontalStrut(10));
            p.add(mouseOverCB);
            p.add(Box.createHorizontalStrut(10));
            recordB = createButton("Record...", p);
            add(p);
        }