Simple Echo program that directly plays audio captured from the microphone

echo.kt

import java.io.FileOutputStream
import java.io.IOException
import java.io.InputStream
import java.io.OutputStream
import javax.sound.sampled.*
import kotlin.concurrent.thread
import kotlin.system.exitProcess

fun main() {
    val format = AudioFormat(16000.0f, 16, 1, true, true)

    val captureInfo = DataLine.Info(TargetDataLine::class.java, format)
    val playbackInfo = DataLine.Info(SourceDataLine::class.java, format)

    // Check if system supports the data line
    if (!AudioSystem.isLineSupported(captureInfo) || !AudioSystem.isLineSupported(playbackInfo)) {
        println("Line not supported")
        exitProcess(0)
    }

    val microphone = AudioSystem.getLine(captureInfo) as TargetDataLine
    val speakers = AudioSystem.getLine(playbackInfo) as SourceDataLine

    microphone.open(format)
    speakers.open(format)

    microphone.start()
    speakers.start()
    var capturing = true
    // Create a thread to capture the microphone data into a buffer and then write to the output stream for playback

    thread {
        try {
            var numBytesRead: Int
            val data = ByteArray(microphone.bufferSize / 5)

            while (true) {
                // Read the next chunk of data from the TargetDataLine.
                numBytesRead = microphone.read(data, 0, data.size)
                // Save this chunk of data.
                speakers.write(data, 0, numBytesRead)
                if (!capturing) break
            }
        } catch (e: java.lang.Exception) {
            e.printStackTrace()
        }
    }

    println("Press ENTER to finish.")
    System.`in`.read()
    capturing = false
    microphone.close()
    speakers.close()
}