CODEWITHSUNDEEP
javaswingappletcompiler-errors
Sam
Sam

Reputation: 3167

Java applets - initialise and instantiate where you declare

Is there anyone here who disagrees that:

JLabel lbl;
lbl = new JLabel ("a label");

is equivalent to:

JLabel lbl = new JLabel ("a label");

I guess not?

Mind you - this is related to the following question:

public class Test 
extends JApplet
{
    JLabel lbl;
    lbl = new JLabel ("a label");
    public void init() 
    {
    }
}

This code (A) gives the following error:

Syntax error on token ";", , expected

However, this code (B) works perfectly:

public class Test 
extends JApplet
{
    JLabel lbl = new JLabel ("a label");
    public void init() 
    {
    }
}

Any idea why this happens? This may have to do with the init method. I'm still looking forward to see mathematical-precise explanations rather than interpretable theories. Thanks a lot. I'm new with applets. PS: I left out the package import (e.g. import javax.swing.*; ) for simplicity.

Upvotes: 1

Views: 235

Answers (3)

vishal_aim
vishal_aim

Reputation: 7854

It has nothing to do with applet or init() method. You can have instructions only inside method body or blocks (lbl = new JLabel ("a label"); without declaration is an instruction)

Upvotes: 2

asgoth
asgoth

Reputation: 35829

It should be the same, IF it is used in a method:

public void setMethod() {
    JLabel lbl;
    lbl = new JLabel ("a label");
}

Upvotes: 2

JB Nizet
JB Nizet

Reputation: 691685

You can't have free instructions like these in the class body. The class body can contain methods, field declarations, constructors, inner classes declarations, static and instance initializer blocks, but not free instructions like this.

You could do

JLabel lbl;

{
    lbl = new JLabel ("a label");
}

but it's ugly.

Upvotes: 2

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