--- a/jdk/src/share/classes/com/sun/media/sound/SoftLowFrequencyOscillator.java	Fri Apr 17 16:20:50 2009 +0400
+++ b/jdk/src/share/classes/com/sun/media/sound/SoftLowFrequencyOscillator.java	Fri Apr 17 16:28:02 2009 +0400
@@ -45,6 +45,13 @@
     private double sin_factor = 0;
     private static double PI2 = 2.0 * Math.PI;
 
+    public SoftLowFrequencyOscillator() {
+        // If sin_step is 0 then sin_stepfreq must be -INF
+        for (int i = 0; i < sin_stepfreq.length; i++) {
+            sin_stepfreq[i] = Double.NEGATIVE_INFINITY;
+        }
+    }
+
     public void reset() {
         for (int i = 0; i < used_count; i++) {
             out[i][0] = 0;
@@ -53,7 +60,8 @@
             freq[i][0] = 0;
             delay_counter[i] = 0;
             sin_phase[i] = 0;
-            sin_stepfreq[i] = 0;
+            // If sin_step is 0 then sin_stepfreq must be -INF
+            sin_stepfreq[i] = Double.NEGATIVE_INFINITY;
             sin_step[i] = 0;
         }
         used_count = 0;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/javax/sound/midi/Gervill/SoftLowFrequencyOscillator/TestProcessControlLogic.java	Fri Apr 17 16:28:02 2009 +0400
@@ -0,0 +1,106 @@
+/*
+ * Copyright 2009 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/* @test
+ @summary Test SoftLowFrequencyOscillator processControlLogic method */
+
+import com.sun.media.sound.AudioSynthesizerPropertyInfo;
+import com.sun.media.sound.SoftLowFrequencyOscillator;
+import com.sun.media.sound.SoftSynthesizer;
+
+public class TestProcessControlLogic {
+
+    private static float control_rate = 147f;
+    private static SoftSynthesizer synth = new SoftSynthesizer();
+    private static SoftLowFrequencyOscillator lfo = new SoftLowFrequencyOscillator();
+
+    private static void testLFO(boolean shared, int instance, float freq, float delay,
+            float delay2) throws Exception {
+        SoftLowFrequencyOscillator lfo =
+            shared?TestProcessControlLogic.lfo:new SoftLowFrequencyOscillator();
+        lfo.reset();
+        double[] lfo_freq = lfo.get(instance, "freq");
+        double[] lfo_delay = lfo.get(instance, "delay");
+        double[] lfo_delay2 = lfo.get(instance, "delay2");
+        double[] lfo_output = lfo.get(instance, null);
+        lfo_freq[0] = freq;
+        lfo_delay[0] = delay;
+        lfo_delay2[0] = delay2;
+        lfo.init(synth);
+
+        // For delayCount amount time, the output LFO should be 0.5
+        int delayCount = (int) ((Math.pow(2, delay / 1200.0) * control_rate));
+        delayCount += (int) ((delay2 * control_rate) / 1000.0);
+        for (int i = 0; i < delayCount; i++) {
+            if (Math.abs(0.5 - lfo_output[0]) > 0.000001)
+                throw new Exception("Incorrect LFO output ("
+                        +"0.5 != "+lfo_output[0]+")!");
+            lfo.processControlLogic();
+        }
+
+        // After the delay the LFO should start oscillate
+        // Let make sure output is accurate enough
+        double p_step = (440.0 / control_rate)
+        * Math.exp((freq - 6900.0) * (Math.log(2) / 1200.0));
+        double p = 0;
+        for (int i = 0; i < 30; i++) {
+            p += p_step;
+            double predicted_output = 0.5 + Math.sin(p * 2 * Math.PI) * 0.5;
+            if (Math.abs(predicted_output - lfo_output[0]) > 0.001)
+                throw new Exception("Incorrect LFO output ("
+                        +predicted_output+" != "+lfo_output[0]+")!");
+            lfo.processControlLogic();
+        }
+
+    }
+
+    public static void main(String[] args) throws Exception {
+
+        // Get default control rate from synthesizer
+        AudioSynthesizerPropertyInfo[] p = synth.getPropertyInfo(null);
+        for (int i = 0; i < p.length; i++) {
+            if (p[i].name.equals("control rate")) {
+                control_rate = ((Float) p[i].value).floatValue();
+                break;
+            }
+        }
+
+        // Test LFO under various configurations
+        for (int instance = 0; instance < 3; instance++)
+            for (int d1 = -3000; d1 < 0; d1 += 1000)
+                for (int d2 = 0; d2 < 5000; d2 += 1000)
+                    for (int fr = -1000; fr < 1000; fr += 100) {
+                        testLFO(true, instance,
+                                (fr == -1000) ? Float.NEGATIVE_INFINITY : fr,
+                                (d1 == -3000) ? Float.NEGATIVE_INFINITY : d1,
+                                d2);
+                        testLFO(false, instance,
+                                (fr == -1000) ? Float.NEGATIVE_INFINITY : fr,
+                                (d1 == -3000) ? Float.NEGATIVE_INFINITY : d1,
+                                d2);
+                    }
+
+    }
+}