Data Type Conversion Just beginning

[Lauren Summers]

Hi everyone,

Im just beginning Java Programming and have read up a little and been doing tutorials well i'll just cut to the chase here.

I have done a simple tutorial which involves an Applet and adds or subtracts two numbers depending on the button clicked.
There is just a small part of the tutorial which isn't explained very well and thats where the conversion from float to string takes place. I just have a question. (Ill post the entire program below everything)

My question is why is what is happening here?

msg1 = txt1.getText();
Float num1 = new Float(msg1);

I understand "msg1 = txt1.getText();" is assigning whatever I type into my first text field to my string variable "msg1" but what is actually happening on the next line? Is this line, "Float num1 = new Float(msg1);", saying take my float from num1 and put it in my string variable msg1? And once in there convert it to a String with this line "msg1 = Float.toString(num1);"?


Thanks to anybody who can understand that question! I really appreciate the help!
Below is the entire program!

import java.applet.*;
import java.awt.*;


public class Testing2 extends Applet {

	float num1, num2, ans;
	String msg1, msg2, msg3;
	Button but1, but2;
	Label lab1, lab2, lab3;
	TextField txt1, txt2, txt3;
	

	public void init() {
		
		but1 = new Button("Add");
		but2 = new Button("Subtract");
		lab1 = new Label("Number 1:");
		lab2 = new Label("Number 2:");
		lab3 = new Label("Answer:");
		txt1 = new TextField(10);
		txt2 = new TextField(10);
		txt3 = new TextField(10);
		
		add(lab1);
		add(txt1);
		add(lab2);
		add(txt2);
		add(but1);
		add(but2);
		add(lab3);
		add(txt3);
	}
	
	public boolean action (Event evt, Object arg) {

		msg1 = txt1.getText();
		Float num1 = new Float(msg1);
		msg2 = txt2.getText();
		Float num2 = new Float(msg2);
		msg1 = Float.toString(num1);
		msg2 = Float.toString(num2);
		
		if (evt.target == but1){
			ans = num1 + num2;
		}
		
		else if (evt.target == but2){
			
			ans = num1-num2;
		}
		
		msg3 = Float.toString(ans);
		txt3.setText(msg3);
		
		
		repaint();
		return(true);
		
		
	}
	
	public void paint (Graphics g){
		
		
	}

}

[Bear Bibeault]

Float num1 = new Float(msg1);  

This line uses the Float constructor to create a new Float object referenced by num1. The value of the Float is the conversion of msg1 to numeric. msg1 itself is unaffected.

See the Javadoc for java.lang.Float (⇐ click that) for more info.

[Stephan van Hulst]

Welcome to CodeRanch, Lauren!