Improved equaliser display

src/uk/co/majenko/audiobookrecorder/Equaliser.java

@@ -15,6 +15,12 @@ public class Equaliser extends JPanel {
 
     EqualiserChannel channels[];
 
+    static final double[] frequencies = {
+        20d, 25d, 31.5d, 40d, 50d, 63d, 80d, 100d, 125d, 160d, 200d,
+        250d, 315d, 400d, 500d, 630d, 800d, 1000d, 1250d, 1600d, 2000d,
+        2500d, 3150d, 4000d, 5000d, 6300d, 8000d, 10000d, 12500d, 16000d,
+        20000d
+    };
 
     public Equaliser() {
         super();
@@ -28,7 +34,7 @@ public class Equaliser extends JPanel {
         inner.setLayout(new FlowLayout());
 
         for (int i = 0; i < 31; i++) {
-            channels[i] = new EqualiserChannel();
+            channels[i] = new EqualiserChannel(frequencies[i]);
             inner.add(channels[i]);
         }
 

src/uk/co/majenko/audiobookrecorder/EqualiserChannel.java

@@ -15,17 +15,35 @@ public class EqualiserChannel extends JPanel {
     float value;
     JSlider slider;
     JTextField textbox;
+    JLabel frequency;
 
-    public EqualiserChannel() {
+    public EqualiserChannel(double freq) {
         super();
 
+
         value = 0;
 
         slider = new JSlider(-120, 120, 0);
         textbox = new JTextField();
 
+        String suffix = "Hz";
+        if (freq > 1000) {
+            freq /= 1000;
+            suffix = "kHz";
+        }
+
+        String ftxt = String.format("%.4f", freq);
+        while (ftxt.endsWith("0")) {
+            ftxt = ftxt.substring(0, ftxt.length() - 1);
+        }
+        if (ftxt.endsWith(".")) {
+            ftxt = ftxt.substring(0, ftxt.length() - 1);
+        }
+        frequency = new JLabel(ftxt + suffix);
+
         setLayout(new BorderLayout());
 
+        add(frequency, BorderLayout.NORTH);
         slider.setOrientation(SwingConstants.VERTICAL);
         add(slider, BorderLayout.CENTER);
         textbox = new JTextField("0.0");