使用 Java 将二进制文件复制到 Mac OSX 剪贴板

Question

我正在编写一个 java 应用程序，它试图将一个 midi 文件复制到 Mac OSX 剪贴板（最终是 Windows）。我尝试将 DataFlavor.javaFileListFlavor 与 getSystemClipboard().setContents 一起使用，但复制到剪贴板的数据无法被 Mac OSX 系统读取，该系统使用类似于 MimeType 的 UTI (https://alastairs-place.net/blog/2012/06/06/utis-are-better-than-you-think-and-heres-why/) 来确定数据类型。是否有一些用于二进制文件（特别是 Midi 文件）的自定义 DataFlavor 代码允许我将文件放在 Mac OS 剪贴板上，类似于我对来自 finder 的文件执行 cmd-c？

这是我目前正在做的事情。

import javax.sound.midi.*;
import java.awt.Toolkit;
import java.util.List;
import java.awt.datatransfer.*;
import java.io.File;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;

/**
 * Created by vincentcimo on 12/22/16.
 */
public class WriteMidi {

public static byte[] longToBytes(long x) {
    ByteBuffer buffer = ByteBuffer.allocate(Long.SIZE / Byte.SIZE);
    buffer.putLong(x);
    return buffer.array();
}

public static void writeFile(String path, ArrayList<LoopNote> notes, double bpm, long loop_length) {
    try {

        long midiTempo = (long) (60000000 / bpm);
        double tickMS = (60 / (bpm * 24)) * 1000;

        /*
        * 24 ticks / beat --- 100 beats / minute
        * tick length = 60 / 100 bpm * 24 pulses per beat
        * */

        //****  Create a new MIDI sequence with 24 ticks per beat  ****
        Sequence s = new Sequence(javax.sound.midi.Sequence.PPQ, 24);

        //****  Obtain a MIDI track from the sequence  ****
        Track t = s.createTrack();

        //****  General MIDI sysex -- turn on General MIDI sound set  ****
        byte[] b = {(byte) 0xF0, 0x7E, 0x7F, 0x09, 0x01, (byte) 0xF7};
        SysexMessage sm = new SysexMessage();
        sm.setMessage(b, 6);
        MidiEvent me = new MidiEvent(sm, (long) 0);
        t.add(me);

        //****  set tempo (meta event)  ****
        MetaMessage mt = new MetaMessage();


        byte[] bt = longToBytes(midiTempo);
        mt.setMessage(0x51, bt, 3);
        me = new MidiEvent(mt, (long) 0);
        t.add(me);

        //****  set track name (meta event)  ****
        mt = new MetaMessage();
        String TrackName = new String("midifile track");
        mt.setMessage(0x03, TrackName.getBytes(), TrackName.length());
        me = new MidiEvent(mt, (long) 0);
        t.add(me);

        //****  set omni on  ****
        ShortMessage mm = new ShortMessage();
        mm.setMessage(0xB0, 0x7D, 0x00);
        me = new MidiEvent(mm, (long) 0);
        t.add(me);

        //****  set poly on  ****
        mm = new ShortMessage();
        mm.setMessage(0xB0, 0x7F, 0x00);
        me = new MidiEvent(mm, (long) 0);
        t.add(me);

        //****  set instrument to Piano  ****
        mm = new ShortMessage();
        mm.setMessage(0xC0, 0x00, 0x00);
        me = new MidiEvent(mm, (long) 0);
        t.add(me);

        for (LoopNote note : notes) {
            mm = new ShortMessage();
            if (note.getVelocity() != 0) {
                mm.setMessage(ShortMessage.NOTE_ON, 1, note.getNote(), note.getVelocity());
            } else {
                mm.setMessage(ShortMessage.NOTE_OFF, 1, note.getNote(), note.getVelocity());
            }
            me = new MidiEvent(mm, (long) (note.getStartTime() / tickMS));
            t.add(me);
        }

        //****  set end of track (meta event) 19 ticks later  ****
        mt = new MetaMessage();
        byte[] bet = {}; // empty array
        mt.setMessage(0x2F, bet, 0);
        me = new MidiEvent(mt, (long) (loop_length / tickMS));
        t.add(me);

        //****  write the MIDI sequence to a MIDI file  ****
        File f = new File(path);
        if (!f.exists()) {
            f.createNewFile();
            MidiSystem.write(s, 1, f);

            List listOfFiles = new ArrayList();
            listOfFiles.add(f);

            FileTransferable ft = new FileTransferable(listOfFiles);

            Toolkit.getDefaultToolkit().getSystemClipboard().setContents(ft, new ClipboardOwner() {
                @Override
                public void lostOwnership(Clipboard clipboard, Transferable contents) {
                    System.out.println("Lost ownership");
                }
            });
        }


    } //try
    catch (Exception e) {
        System.out.println("Exception caught " + e.toString());
    } //catch
    System.out.println("midifile end ");


}

public static class FileTransferable implements Transferable {

    private List listOfFiles;

    public FileTransferable(List listOfFiles) {
        this.listOfFiles = listOfFiles;
    }

    @Override
    public DataFlavor[] getTransferDataFlavors() {
        return new DataFlavor[]{DataFlavor.javaFileListFlavor};
    }

    @Override
    public boolean isDataFlavorSupported(DataFlavor flavor) {
        return DataFlavor.javaFileListFlavor.equals(flavor);
    }

    @Override
    public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException {
        return listOfFiles;
    }
}

  }

这是一个类似的帖子，但从未得到回复：

What is the required DataFlavor to copy files in Mac OSX

Answer 1

我遇到了同样的问题，经过数小时的搜索，我想出了以下简单的解决方法。在 Java 中，您调用一个终端命令，它运行一个苹果脚本，告诉 Finder 将文件放入剪贴板：

public static void copyToClipboard(String filepath) {
      String[] cmd = {"osascript", "-e", "tell app \"Finder\" to set the clipboard to ( POSIX file \""+filepath+"\" )"};
    try {
        Runtime.getRuntime().exec(cmd);
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

然后您可以通过 cmd + v 粘贴文件，就像在 finder 中复制它一样。