import util.comm.*;
import util.MoreOutputStream;

/**
 * This class will compute in parallel (using threads) the result of
 *   2
 * Ax  - Bx + C
 *
 * And generate values suitable for plotting from 1 to 10.
 * First we decompose it into a postfix notation:
 *
 * ((x x *) A *) (B x *) - ) C +
 *
 * and decide how many threads we need:
 *	    a      b      op
 *       +----------------------+
 * res1	 :  X      X      *
 * res2  :  B      X      *
 * res3  :  res1   A      *
 * res4  :  res3   res2   -
 * res5  :  res4   C      +
 *
 * A total of 5 threads with the result coming out on result 5.
 *
 * A total of 5 + 4 data channels.
 *
 */
public class Quadratic {
    public static void main(String args[]) {
    	DataChannel	X = DataChannel.getChannel("X");
    	DataChannel	X2 = DataChannel.getChannel("X2");
    	DataChannel	A = DataChannel.getChannel("a");
    	DataChannel	B = DataChannel.getChannel("b");
    	DataChannel	C = DataChannel.getChannel("c");
    	DataChannel	answer = DataChannel.getChannel("res5",
    					Thread.currentThread(), 2);
    	Computer	res[] = new Computer[5];

	    System.out = new java.io.PrintStream(new MoreOutputStream());

    	res[0] = Computer.create("X", "X2", "res1", Computer.MUL);
    	res[1] = Computer.create("X", "b", "res2", Computer.MUL);
    	res[2] = Computer.create("res1", "a", "res3", Computer.MUL);
    	res[3] = Computer.create("res3", "res2", "res4", Computer.SUB);
    	res[4] = Computer.create("res4", "c", "res5", Computer.ADD);
    	/* now start them up. */
    	for (int i = 0; i < res.length; i++) res[i].start();

    	/* now write in the values. */
    	for (int i = 0; i < 5; i++) {
	        C.putValue(new Integer(10));
	        B.putValue(new Integer(5));
	        A.putValue(new Integer(3));
	        X.putValue(new Integer(i));
	        X2.putValue(new Integer(i));
 	        int check = ((i * i) * 3) - (5 * i) + 10;
	        try {
	            System.out.println("X = "+i+", result = "+
		   			((Integer) answer.getValue())+
					" ["+check+"]");
	        } catch (DataChannelException e) {
		        System.out.println("Overrun on the answer!");
            }
	    }
	    for (int i = 0; i < res.length; i++) res[i].stop();
	    try {
	        Thread.currentThread().sleep(1000);
	    } catch (InterruptedException e) { }
    }
}