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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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 * IN THE SOFTWARE.
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 * IN THE SOFTWARE.
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 ******************************************************************************/
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 ******************************************************************************/
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import java.util.Comparator;
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import java.util.Vector;
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import java.util.Vector;
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import java.lang.ClassCastException;
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import java.lang.ClassCastException;
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class SJFScheduler implements Scheduler
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class SJFScheduler extends Scheduler
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{
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{
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    /**
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     * An SJFProcess is a Process with these additions:
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     * 1) It has an add time associated with it
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     */
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    private class SJFProcess implements Comparable
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    private class SJFProcess extends Process
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    {
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    {
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        public final Process proc;
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        public final int add_time;
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        public final int add_time;
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        public SJFProcess (Process proc, int add_time)
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        public SJFProcess (String name, int timeslice, int add_time)
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        {
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        {
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            this.proc = proc;
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            super(name, timeslice);
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            this.add_time = add_time;
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            this.add_time = add_time;
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        }
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        }
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        // negative if this < rhs
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        // positive if this > rhs
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        public int compareTo (Object o)
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        {
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            if (! (o instanceof SJFProcess))
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                throw new ClassCastException();
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            SJFProcess rhs = (SJFProcess)o;
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            return this.add_time - rhs.add_time;
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        }
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    }
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    }
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    private Vector<SJFProcess> processes;
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    private Vector<SJFProcess> wait_queue;
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    public SJFScheduler ()
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    public SJFScheduler ()
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    {
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    {
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        super ();
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        this.processes = new Vector<SJFProcess> ();
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        this.wait_queue = new Vector<SJFProcess> ();
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    }
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    }
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    public void addProcess (Process proc, int add_time)
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    public void addProcess (Process proc, int add_time)
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    {
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    {
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        wait_queue.add (new SJFProcess (proc.name, proc.timeslice, add_time));
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    }
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    }
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    public void run ()
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    private Process findShortest ()
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    {
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    {
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        Process shortest = new Process ("fake", Integer.MAX_VALUE);
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        for (Process p : run_queue)
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            if (p.timeslice < shortest.timeslice)
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                shortest = p;
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        return shortest;
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    }
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    protected boolean step ()
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    {
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        /* Leave if we are truly done */
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        if (cur_proc == null && run_queue.isEmpty () && wait_queue.isEmpty ())
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            return false;
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        /* Create a clone of wait_queue. This is so we can delete things from
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         * the actual wait_queue, while iterating over it */
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        Vector<SJFProcess> wq_clone = (Vector<SJFProcess>)wait_queue.clone ();
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        /* Pull anything that gets added at this time into run_queue */
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        for (SJFProcess p : wq_clone)
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            if (p.add_time == cur_time)
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            {
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                wait_queue.remove (p);
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                run_queue.add (p);
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            }
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        /* If there is no process, then get one! */
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        if (cur_proc == null)
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            startProcess (findShortest ());
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        /* If the current process is set to run, do so, return false */
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        if (cur_proc.time_left > 0)
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            scheduleCurrent ();
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        else
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            completeCurrent ();
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        return true;
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    }
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    }
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}
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}
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/* vim: set ts=4 sts=4 sw=4 expandtab: */
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/* vim: set ts=4 sts=4 sw=4 expandtab: */
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