import java.awt.*;import java.applet.*;import java.io.*;import java.net.*;import java.util.*;class ControlPanel extends Panel {    AlgAnimFrame frame;    Button run_button, stop_button, step_button;    Choice data_choice, delay_choice;    int data_selected = 0;    TextField mesg;    public ControlPanel(AlgAnimFrame frame, String algname) {	setBackground( Color.white );	GridBagLayout gb = new GridBagLayout();	GridBagConstraints gc = new GridBagConstraints();	gc.insets = new Insets(5, 5, 5, 5);	setLayout(gb);	gc.fill = GridBagConstraints.BOTH;	gc.weightx = 1.0;	        this.frame = frame;        run_button = new Button("Run " + algname);	gb.setConstraints(run_button, gc);        this.add(run_button);		step_button = new Button("Next Step");	gb.setConstraints(step_button, gc);	this.add(step_button);        stop_button = new Button("Stop");        stop_button.disable();	gb.setConstraints(stop_button, gc);        this.add(stop_button);        data_choice = new Choice();        // assigning data sets        for (int i = 0; i < frame.alg.dataSets.length; i++)            data_choice.addItem(frame.alg.dataSets[i]);	data_choice.select(0);	gc.gridwidth = GridBagConstraints.REMAINDER;	gb.setConstraints(data_choice, gc);	this.add(data_choice);		delay_choice = new Choice();	delay_choice.addItem("Delay 200msec");	delay_choice.addItem("Delay 400msec");	delay_choice.addItem("Delay 600msec");	delay_choice.addItem("Delay 800msec");	delay_choice.addItem("Delay 1000msec");	delay_choice.select(2);	gc.gridwidth = GridBagConstraints.REMAINDER;	gc.insets = new Insets(5, 5, 5, 200);	gb.setConstraints(delay_choice, gc);		this.add(delay_choice);		mesg = new TextField(50);	mesg.disable();	gc.insets = new Insets(5, 5, 5, 5);	gb.setConstraints(mesg, gc);	this.add(mesg);    } // ControlPanel()    public boolean action(Event e, Object arg) {        Object target = e.target;         if (target == run_button) {	    setText("Running algorithm continuously...");            frame.startAlg();            return true;        } else if (target == stop_button) {	    setText("Stop button pressed...");	    frame.setStep(false);            if (frame.alg.isAlive())                frame.alg.stop();            frame.finishAlg();            return true;	} else if (target == step_button) {	    setText("Executing next step...");	    frame.setStep(true);	    if (!frame.alg.isAlive())		frame.startAlg();	   // else		//frame.alg.resume();	    return true;        } else if (target instanceof Choice) {	    if (target == data_choice) {		data_selected = data_choice.getSelectedIndex();		frame.alg.generateData();		setText("Data generated...");	    } else if (target == delay_choice) {		//System.out.println("delay");		frame.delay = (delay_choice.getSelectedIndex() + 1) * 200;		//frame.alg.setDelay(frame.delay);		setText("Animation delay now set to " + frame.delay + " msec...");	    }        }        return false;    } // action()    public int getDataChoice() {        return data_selected;    }    public void setText(String str) {	mesg.setText(str);    }} // class ControlPanel