package com.sedmelluq.discord.lavaplayer.demo.jda;

import com.sedmelluq.discord.lavaplayer.player.AudioPlayer;
import com.sedmelluq.discord.lavaplayer.track.playback.AudioFrame;
import net.dv8tion.jda.audio.AudioSendHandler;

/**
 * This is a wrapper around AudioPlayer which makes it behave as an AudioSendHandler for JDA. As JDA calls canProvide
 * before every call to provide20MsAudio(), we pull the frame in canProvide() and use the frame we already pulled in
 * provide20MsAudio().
 */
public class AudioPlayerSendHandler implements AudioSendHandler {
  private final AudioPlayer audioPlayer;
  private AudioFrame lastFrame;

  /**
   * @param audioPlayer Audio player to wrap.
   */
  public AudioPlayerSendHandler(AudioPlayer audioPlayer) {
    this.audioPlayer = audioPlayer;
  }

  @Override
  public boolean canProvide() {
    lastFrame = audioPlayer.provide();
    return lastFrame != null;
  }

  @Override
  public byte[] provide20MsAudio() {
    return lastFrame.data;
  }

  @Override
  public boolean isOpus() {
    return true;
  }
}

package com.sedmelluq.discord.lavaplayer.demo.jda;

import com.sedmelluq.discord.lavaplayer.player.AudioPlayer;
import com.sedmelluq.discord.lavaplayer.track.playback.AudioFrame;
import net.dv8tion.jda.audio.AudioSendHandler;

/**
 * This is a wrapper around AudioPlayer which makes it behave as an AudioSendHandler for JDA. As JDA calls canProvide
 * before every call to provide20MsAudio(), we pull the frame in canProvide() and use the frame we already pulled in
 * provide20MsAudio().
 */
public class AudioPlayerSendHandler implements AudioSendHandler {
  private final AudioPlayer audioPlayer;
  private AudioFrame lastFrame;

  /**
   * @param audioPlayer Audio player to wrap.
   */
  public AudioPlayerSendHandler(AudioPlayer audioPlayer) {
    this.audioPlayer = audioPlayer;
  }

  @Override
  public boolean canProvide() {
    if (lastFrame == null) {
      lastFrame = audioPlayer.provide();
    }

    return lastFrame != null;
  }

  @Override
  public byte[] provide20MsAudio() {
    if (lastFrame == null) {
      lastFrame = audioPlayer.provide();
    }

    byte[] data = lastFrame != null ? lastFrame.data : null;
    lastFrame = null;

    return data;
  }

  @Override
  public boolean isOpus() {
    return true;
  }
}

Make it safe to call canProvide multiple times (or not at all).
Make it safe to call canProvide multiple times (or not at all).
