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-rw-r--r--timer/com/vladium/utils/timing/HRTimer.java86
1 files changed, 86 insertions, 0 deletions
diff --git a/timer/com/vladium/utils/timing/HRTimer.java b/timer/com/vladium/utils/timing/HRTimer.java
new file mode 100644
index 0000000..a3673a1
--- /dev/null
+++ b/timer/com/vladium/utils/timing/HRTimer.java
@@ -0,0 +1,86 @@
+
+package com.vladium.utils.timing;
+
+// ----------------------------------------------------------------------------
+/**
+ * A package-private implementation of {@link ITimer} based around native
+ * <code>getTime</code> method. It will work on any platform for which a JNI
+ * implementation of "hrtlib" library is available.<P>
+ *
+ * {@link TimerFactory} acts as the Factory for this class.<P>
+ *
+ * MT-safety: an instance of this class is safe to be used within the same
+ * thread only.
+ *
+ * @author (C) <a href="mailto:vroubtsov@illinoisalumni.org">Vlad Roubtsov</a>, 2002
+ */
+final class HRTimer implements ITimer, ITimerConstants
+{
+ // public: ................................................................
+
+ public void start ()
+ {
+ if (DO_STATE_CHECKS)
+ {
+ if (m_state != STATE_READY)
+ throw new IllegalStateException (this + ": start() must be called from READY state, current state is " + STATE_NAMES [m_state]);
+ }
+
+ if (DO_STATE_CHECKS) m_state = STATE_STARTED;
+ m_data = getTime ();
+ }
+
+ public void stop ()
+ {
+ // latch stop time in a local var before doing anything else:
+ final double data = getTime ();
+
+ if (DO_STATE_CHECKS)
+ {
+ if (m_state != STATE_STARTED)
+ throw new IllegalStateException (this + ": stop() must be called from STARTED state, current state is " + STATE_NAMES [m_state]);
+ }
+
+ m_data = data - m_data;
+ if (DO_STATE_CHECKS) m_state = STATE_STOPPED;
+ }
+
+ public double getDuration ()
+ {
+ if (DO_STATE_CHECKS)
+ {
+ if (m_state != STATE_STOPPED)
+ throw new IllegalStateException (this + ": getDuration() must be called from STOPPED state, current state is " + STATE_NAMES [m_state]);
+ }
+
+ return m_data;
+ }
+
+ public void reset ()
+ {
+ if (DO_STATE_CHECKS) m_state = STATE_READY;
+ }
+
+ // protected: .............................................................
+
+ // package: ...............................................................
+
+ // private: ...............................................................
+
+ /*
+ * This is supposed to return a fractional count of milliseconds elapsed
+ * since some indeterminate moment in the past. The exact starting point
+ * is not relevant because this timer class reports time differences only.
+ *
+ * JNI code in HRTIMER_LIB library is supposed to implement this. */
+ private static native double getTime ();
+
+
+ private int m_state; // used to keep track of timer state
+ private double m_data; // timing data
+
+ private static final String HRTIMER_LIB = "hrtlib";
+
+
+} // end of class
+// ----------------------------------------------------------------------------