Help understanding this syntax -- new object returned

I was reading an Android tutorial and came across this block of code:

Code :

---

protected Dialog onCreateDialog( int id )
{
	return new AlertDialog.Builder( this )
        	       .setTitle( "Planets" )
        	       .setMultiChoiceItems( _options, _selections, new DialogSelectionClickHandler() )
        	       .setPositiveButton( "OK", new DialogButtonClickHandler() )
        	       .create();
}

---

Can someone explain how this works? How can you invoke the setTitle(), setMultiChoiceItems(), and other methods like this without specifying an object name. I'm sure it's correct -- I've just never seen it before.

Normally I would do something like:

Code :

---

protected Dialog onCreateDialog( int id )
{
 
    Dialog d = new AlertDialog.Builder(this);
    d.setTitle( "Planets" );
    d.setMultiChoiceItems( _options, _selections, new DialogSelectionClickHandler() );
    d.setPositiveButton( "OK", new DialogButtonClickHandler() )
    d.create();
 
    return d;
}

---

Does anyone know what that type of initialization used in the tutorial is called so I can read about it? I tried to look it up in a java reference book but couldn't find anything on it.

Thanks for your help.

The compiler is ignoring white spaces.
Edit out the white spaces to get:
AlertDialog.Builder( this ).setTitle( "Planets" ).setMultiChoiceItems( _options, _selections, new DialogSelectionClickHandler() ).setPositiveButton( "OK", new DialogButtonClickHandler() ).create();

Each of the methods must return an object that can be used by the next method. <<<<<<<< Check this in the doc

Really ugly code. Must be generated by an IDE.

You are absolutely correct. I cannot believe I didn't realize it myself. I've been away from java for a while so I assumed this was some new syntactic sugar. I agree with you that it's quite ugly, but it's not auto-generated code, it's from a book on developing android applications. Maybe this is a java convention when chaining methods?

Thanks for your help. I have a hard time moving on with stuff when I don't completely understand what's happening.

Maybe with the small windows they want everything in a narrow column and with as few statements as possible. Although I think the compiler has to generate variables to hold the returned objects so I'm not sure the generated code would be any smaller.

The compiler code, as I understand it, would just do...

Code :

---

create AlertDialog.Builder
store
call setTitle
store
call setMultiChoiceItems
store
call setPositiveButton
store
call create
store
return

---

On the top one anyway

The second one would be optimized down to doing the same thing, and it would be a lot prettier