java - 有没有办法在 Java 中获取所有 MIDI 设备的列表？

Question

我正在尝试用 Java 获取所有 MIDI 设备，这比我想象的要难......

我尝试了for each()循环，但它不起作用，因为我不知道ArrayList我在用这个方法做什么。

这是我的代码：

package com.example.cmmp.midi;

import javax.sound.midi.*;
import javax.sound.midi.spi.MidiDeviceProvider;
import java.util.*;

@SuppressWarnings("unchecked")
public class MidiDeviceReceiver {
    private static MidiSystem MidiDevice;

    public static Sequencer getSequencer() throws MidiUnavailableException {
        return MidiSystem.getSequencer ();
    }
    public static List<MidiDevice> getMidiDevices(){
        javax.sound.midi.MidiDeviceReceiver midiDeviceReceiver = new javax.sound.midi.MidiDeviceReceiver () {
            public MidiSystem MidiDevice;
            public void send(MidiMessage message, long timeStamp) {

            }
//close
            public void close() {

            }

            public MidiDevice getMidiDevice() {
                MidiDeviceProvider midi = new MidiDeviceProvider () {
                    public MidiDevice.Info[] getDeviceInfo() {
                        return new MidiDevice.Info[0];
                    }

                    public MidiDevice getDevice(MidiDevice.Info info) {
                        try {
                            MidiDevice = (MidiSystem) MidiSystem.getMidiDevice ( info );
                        } catch (MidiUnavailableException e) {
                            e.printStackTrace ();
                        }
                        return (javax.sound.midi.MidiDevice) MidiDevice;
                    }
                };
                return (javax.sound.midi.MidiDevice) MidiDevice;
            }
        };
        return (List<javax.sound.midi.MidiDevice>) MidiDevice;
    }
}

任何帮助，将不胜感激。

Answer 1

您可以像这样枚举所有 MidiDevices：

package org.example2;

import javax.sound.midi.MidiDevice;
import javax.sound.midi.MidiSystem;
import javax.sound.midi.MidiUnavailableException;

public class App2 {

    public static void main(String[] args) throws MidiUnavailableException {
        MidiDevice.Info[] devices = MidiSystem.getMidiDeviceInfo();
        for (MidiDevice.Info info : devices) {
            try {
                MidiDevice device = MidiSystem.getMidiDevice(info);
                System.out.println(info.getDescription() + " " + device.toString());
            } catch (MidiUnavailableException e) {
                System.out.println("Device " + info.getDescription() + " is not available");
                e.printStackTrace();
            }
        }
    }
}

当然，这会为您提供调用该函数时存在的设备的静态列表——如果有人插入/拔出设备，则该列表将过期。