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From: haig on 10 Jan 2006 15:18
Hello

Ik get an error on this piece of code:

if((word.charAt(i)).equals("a"){
.....
}

Error: char cannot be dereferenced

Can someone tell me what's wrong? Or how can I compare each letter of the
word to the "a"?

Thanks
From: James Westby on 10 Jan 2006 15:25
haig wrote:
> Hello
>
> Ik get an error on this piece of code:
>
> if((word.charAt(i)).equals("a"){
> ....
> }
>
> Error: char cannot be dereferenced
>
> Can someone tell me what's wrong? Or how can I compare each letter of the
> word to the "a"?
>
> Thanks


Try

..equals('a'){

becomes

== 'a'){


James
From: VisionSet on 10 Jan 2006 15:29

"haig" <haigremove(a)pandora.be> wrote in message
news:mEUwf.93178$JO4.6047840(a)phobos.telenet-ops.be...
> Hello
>
> Ik get an error on this piece of code:
>
> if((word.charAt(i)).equals("a"){
> ....
> }
>
> Error: char cannot be dereferenced

word.charAt(i) returns a char primitive, you can not call methods on a
primitive ie equals(String str)
For that matter you must make the two objects of the same type to make
equals meaningful.

so

objectOneOfTypeA.equals(objectTwoOfTypeA) // is okay

to modify your example

char chrPrim = word.charAt(i);
Character chrObject = Character.valueOf(chrPrim);
boolean isEqual = Character.valueOf('a').equals(chrObject);

but since you have a primitive it is easier to just do

if ( word.charAt(i) == 'a' ) {...} // !!

--
Mike W


From: haig on 10 Jan 2006 15:39
"VisionSet" <spam(a)ntlworld.com> wrote in news:WOUwf.32187$yu.5572
@newsfe6-gui.ntli.net:


> word.charAt(i) returns a char primitive, you can not call methods on a
> primitive ie equals(String str)
> For that matter you must make the two objects of the same type to make
> equals meaningful.
>
> so
>
> objectOneOfTypeA.equals(objectTwoOfTypeA) // is okay
>
> to modify your example
>
> char chrPrim = word.charAt(i);
> Character chrObject = Character.valueOf(chrPrim);
> boolean isEqual = Character.valueOf('a').equals(chrObject);
>
> but since you have a primitive it is easier to just do
>
> if ( word.charAt(i) == 'a' ) {...} // !!
>

Thanks

And if I want to compare a string of vouwels

String [] vouwels = {"A", "a", "E", "e", "U", "u", "I", "i", "O", "o"};

if(word.charAt(i) == vouwels[j]){} //?

So I need to count the vouwels in a word...

From: Roedy Green on 10 Jan 2006 15:49
On Tue, 10 Jan 2006 20:25:45 GMT, James Westby <jw2328(a)bris.ac.uk>
wrote, quoted or indirectly quoted someone who said :

>> if((word.charAt(i)).equals("a"){

You have two problems. equals is for comparing objects; == is for
comparing primitives. You have primitives. Secondly your () don't
balance.
--
Canadian Mind Products, Roedy Green.
http://mindprod.com Java custom programming, consulting and coaching.
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