ch15l02.txt

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Listing 15.2 The SpinText implementation.

import java.awt.*;

public class SpinText implements Runnable{
    Thread myThread;
    String msg;
    String outStr;
    char spinChar;
    int cols;
    int inSpin;
    long sleepDelay;
    Graphics g;
    boolean inBlock;
    boolean charInSpin[];
    char displayLine[];

    public SpinText() {
    }

    public SpinText(String m, Long sleepDIn, Graphics gIn) {
        g = gIn;
        sleepDelay = sleepDIn.longValue();
        cols = m.length();
        msg = m;
        displayLine = new char[msg.length()];
        spinChar = ' ';
        charInSpin = new boolean[cols];
        for(int i = 0; i < cols; i++){
            charInSpin[i] = true;
            displayLine[i] = spinChar;
        }
        inSpin = cols;
        inBlock = true;
        }

    public void run(){
        inSpin = cols;
        spinChar = ' ';
        g.setFont(new Font("Courier", Font.PLAIN, 12));
        while(inSpin > 0){
            int i;
            for(i = 0; i < cols; i++){
                if(charInSpin[i] == true){
                    displayLine[i] = spinChar;
                    if(msg.charAt(i) == spinChar){
                        charInSpin[i] = false;
                        inSpin--;
                    }
                }
            }
            outStr = new String(displayLine);
            this.paint(g);
            switch(spinChar){
            case(' ') :
                spinChar = 'a';  //start with the lower-case letters
                break;
            case('z') :
                spinChar = '.';  //roll over to punctuation -- note that I
                                 //skip exclamation pt., quote marks, and
                                 //some others
                break;
            default:
                spinChar++;
            }
            try{
                Thread.sleep(sleepDelay);
            }catch (Exception e){
                return;
            }
        }
        inBlock = false;
    }

    public void paint(Graphics g){
            g.clearRect(0, 0, 300, 300);
            g.drawString(outStr, 100, 100);
    }

    public boolean inBlock(){
        return inBlock;
    }
}