double fa=220, fb=0;
SourceDataLine speaker;
AudioFormat af = new AudioFormat(44100f, 16, 1, true, false);
DataLine.Info info = new DataLine.Info(SourceDataLine.class, af);
speaker = (SourceDataLine) AudioSystem.getLine(info);
speaker.open(af, 4096);
speaker.start();
double t = 0;
short[] buff = new short[256];
byte[] toSoundCard = new byte[buff.length*2];
for (;;) {
        if(t>=1) break;
            System.out.println(t+" "+e.getValueAt(t));
            for (int i = 0; i < buff.length; i++) {
        double f=lerp(fa,fb,t);
        //System.out.println(f);
                buff[i] = (short) (Short.MAX_VALUE * 0.5 * Math.sin(t * Math.PI * 2 * f));
                toSoundCard[2 * i] = (byte) buff[i];
                toSoundCard[2 * i + 1] = (byte) (buff[i] >> 8);   //(i know i could avoid doing this)
                t += 1.0 / 44100.0;
            }
            speaker.write(toSoundCard, 0, toSoundCard.length);
        }`

where lerp is this function:
 public static final double lerp(double a, double b, double f) {
        double fn = f > 1 ? 1 : f < 0 ? 0 : f;
        return a * (1 - fn) + b * fn;
    }