java.util.Scanner

[ronicasingh]

Hello all very advanced programmers.

I'm a amateur programmer still learning to climb the ropes. I am trying to run a certain program on Java but seem to get some errors that does not define itself any further.

These are the errors I am currently getting when I compile the program:

BrownianZombies.java:183: cannot resolve symbol
symbol : class Scanner
location: class BrownianZombies
static Scanner input;
^
BrownianZombies.java:217: cannot resolve symbol
symbol : class Scanner
location: class BrownianZombies
input = new Scanner(pr.getInputStream());
^
2 errors

What I did is I commented these two lines out, and try compiling again. Another error:

BrownianZombies.java:95: cannot resolve symbol
symbol : variable input
location: class BrownianZombies
String dir = input.next();
^
1 error

With this line I could not comment out, because there was a whole lot other variables to consider. So, I changed the above to String dir = "";

I am working with J2SDK 1.4.1_04.

Any ideas?

I've attached the program I'm working with, it is actually from another site. I'm just trying to run it to get an idea of what is required.

Ronica

[sciwizeh]

it compiled fine for me... what are you using to compile it? what IDE, if any?

[ronicasingh]

Hi,

IDE, not sure but I use normal notepad as an editor, and Java 2 SDK SE 1.4.1_04 Runtime Environment.

What do you use? Tried on JBuilder as well, still do not know how to get that going.

Did you use any arguments?

[sciwizeh]

i use bluej

no arguments

what is it actually supposed to do, running it it asked for an executable, what should i pass?

this is what you are trying to compile:

import java.util.*;
import javax.swing.*;
import java.io.*;
import java.security.*;
import java.awt.*;
import java.awt.event.*;

public class BrownianZombies extends JFrame{
    int[] zx, zy;
    int x, y;
    int[] idx;
    boolean[][] visited;
    double p;
    Random r;
    int delay = 100;
    boolean novis, history;
    void generate(String seed){
        try{
            r = SecureRandom.getInstance("SHA1PRNG");
            r.setSeed(Integer.parseInt(seed));
        } catch (Exception e) {   
            e.printStackTrace();
        }
        int[] tx = new int[10000];
        int[] ty = new int[10000];
        idx = new int[10000];
        visited = new boolean[100][100];
        int ptr = 0;
        p = r.nextDouble()*0.1+0.05;
        for(int i = 0; i<idx.length; i++)idx[i] = i;

        for(int i = 0; i<100; i++)for(int j = 0; j<100; j++){
            if(i >= 5 || j >= 5)if(r.nextDouble() < p){
                tx[ptr] = i;
                ty[ptr] = j;
                ptr++;
            }
        }
        zx = new int[ptr];
        zy = new int[ptr];
        for(int i = 0 ;i<ptr; i++){
            zx[i] = tx[i];
            zy[i] = ty[i];
        }

    }
    public void move(){
        for(int i = 0; i<zx.length; i++){
            int s = r.nextInt(i+1);
            int t = idx[i];idx[i] = idx[s];idx[s] = t;
        }
        for(int i = 0; i<zx.length; i++){
            int xx = zx[idx[i]] + r.nextInt(3) - 1;
            int yy = zy[idx[i]] + r.nextInt(3) - 1;
            if(xx < 100 && yy < 100 && xx >= 0 && yy >= 0){
                zx[idx[i]] = xx;
                zy[idx[i]] = yy;
            }
        }
    }

    int lives = 10;
    int T;
    public boolean ok(){
        for(int i = 0; i<zx.length; i++)if(x == zx[i] && y == zy[i])lives--;
        return lives >= 0;
    }

    public String checkData(String s){return "";}
    public double runTest(String lt){
        try{
            
            int time = 10000;
            generate(lt);
            StringBuffer sb = new StringBuffer();
            sb.append(zx.length).append('\n');
            os.write(sb.toString().getBytes());
            os.flush();
            int score = 30000; T = 0;
            if(history)visited[0][0] = true;
            while((x != 99 || y != 99) && T < 10000){
                T++;
                sb.delete(0,sb.length());
                sb.append(zx[0]);
                for(int i = 1; i<zx.length; i++)
                    sb.append(' ').append(zx[i]);
                sb.append('\n');
                sb.append(zy[0]);
                for(int i = 1; i<zy.length; i++)
                    sb.append(' ').append(zy[i]);
                sb.append('\n').append(x).append(' ').append(y).append('\n');
                os.write(sb.toString().getBytes());
                os.flush();

                String dir = input.next();
		        if(dir.equals("S")){
                }else if(dir.equals("R")){
                    x++;
                }else if(dir.equals("L")){
                    x--;
                }else if(dir.equals("U")){
                    y--;
                }else if(dir.equals("D")){
                    y++;
                }else if(dir.equals("RU")){
                    x++;
                    y--;
                }else if(dir.equals("LU")){
                    x--;
                    y--;
                }else if(dir.equals("RD")){
                    x++;
                    y++;
                }else if(dir.equals("LD")){
                    x--;
                    y++;
                }else{
                    System.out.println("Invalid Direction: "+dir);
                    return 0;
                }
                if(x < 0)x = 0;
                if(y < 0)y = 0;
                if(x == 100)x = 99;
                if(y == 100)y = 99;
                if(!ok()){
                    System.out.println("Brains... Score = "+T);
                    return T;
                }
                move();
                if(!ok()){
                    System.out.println("Brains... Score = "+T);
                    return T;
                }
                score -= 2;
                if(!novis){
                    if(history)visited[x][y] = true;
                    repaint();
                    Thread.sleep(delay);
                }
            }
            System.out.println("Score: "+(score + lives * 1000));
            return score + (x != 99 || y != 99 ? 0 : lives * 1000);
        }catch(Exception e){
            e.printStackTrace();
            return 0;
        }
    }
    class Vis extends JPanel{
        public void paint(Graphics g){
            if(zx == null)return;
            Graphics2D g2 = (Graphics2D)g;
            g2.setColor(new Color(200,200,200));
            g2.fillRect(0,0,getWidth(),getHeight());
            Font f = new Font(g2.getFont().getName(),Font.PLAIN,20);
            g2.setFont(f);
            FontMetrics fm = g2.getFontMetrics();
            int th = fm.getAscent();
            int mul = Math.max(1,Math.min((getWidth()-1)/100,(getHeight()-1-2*th)/100));
            int[][] cnt = new int[100][100];
            for(int i = 0; i<zx.length; i++){
                cnt[zx[i]][zy[i]]++;
            }
            for(int i = 0; i<100; i++){
                for(int j = 0; j<100; j++){
                    if(cnt[i][j] == 1)g.setColor(Color.red);
                    else if(cnt[i][j] > 1)g.setColor(Color.magenta);
                    else if(visited[i][j])g.setColor(Color.cyan);
                    else g.setColor(Color.white);
                    if(i == x && j == y)g.setColor(Color.blue);
                    g.fillRect(mul*i+1,2*th+mul*j+1,mul,mul);
                }
            }
            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
            String txt = "Moves Made: "+T;
            g.setColor(Color.black);
            g.drawString(txt,0,th);
            txt = "Lives left : "+lives;
            g.drawString(txt,0,2*th);
        }
    }
    static Process pr;
    static Scanner input;
    static InputStream error;
    static DataOutputStream os;
    public static void main(String[] args) throws IOException{
        BrownianZombies b = new BrownianZombies();
        String exec = null;
        String seed = "1";
        for(int i = 0; i<args.length; i++){
            if(args[i].equals("-delay")){
                b.delay = Integer.parseInt(args[++i]);
            }else if(args[i].equals("-seed")){
                seed = args[++i];
            }else if(args[i].equals("-novis")){
                b.novis = true;
            }else if(args[i].equals("-history")){
                b.history = true;
            }else{
                exec = args[i];
            }
        }
        if(exec == null){
            System.out.println("Please enter an executable");
            System.exit(1);
        }
        //for(int i = 0; i<b.zx.length; i++){
            //System.out.println(i+" "+b.zx[i]+" "+b.zy[i]);
        //}
        if(!b.novis){
            b.add(b.new Vis());
            b.setSize(450,450);
            b.setVisible(true);
            b.addWindowListener(new Closer());
        }
        pr = Runtime.getRuntime().exec(args[0]);
        input = new Scanner(pr.getInputStream());
        error = pr.getErrorStream();
        os = new DataOutputStream(pr.getOutputStream());

        new ErrorReader().start();
        b.runTest(seed);
        pr.destroy();
    }
    public String displayTestCase(String s){
        generate(s);
        return "p = "+p;
    }
    public double[] score(double[][] d){
        double[] ret = new double[d.length];
        for(int i = 0; i<ret.length; i++)
            for(int j = 0; j<d[0].length; j++)
                ret[i] += d[i][j];
        return ret;
    }
    static class ErrorReader extends Thread{
        public void run(){
            try{
                byte[] ch = new byte[50000];
                int read;
                while((read = error.read(ch)) > 0){
                    String s = new String(ch,0,read);
                    //System.out.println("err: "+s+" "+s.endsWith("\n"));
                    System.out.print(s);
                }
                System.out.println();
            }catch(Exception e){
                //System.err.println("Failed to read from stderr");
            }
        }
    }
    static class Closer implements WindowListener{
        public void windowActivated(WindowEvent e){}
        public void windowDeactivated(WindowEvent e){}
        public void windowOpened(WindowEvent e){}
        public void windowClosing(WindowEvent e){ 
            pr.destroy();
            System.exit(0); 
        }
        public void windowClosed(WindowEvent e){}
        public void windowIconified(WindowEvent e) {}
        public void windowDeiconified(WindowEvent e) {}
    }
}

correct?