# Class Constructor Block not working
**URL:** https://discourse.processing.org/t/class-constructor-block-not-working/16282
**Category:** Coding Questions
**Created:** [December 10, 2019, 5:00am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282 "2019-12-10T05:00:27Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 5:00am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/1 "2019-12-10T05:00:27Z")
So I’m just starting out on processing and I run into this error:
Unexpected token: {
Here is my code:
```auto
Person joe;
void setup(){
size(500,500);
background(0);
Person joe = new Person();
}
void draw(){
joe.display();
}
Class Person(){
String shape;
color c;
Person(){
c=color((mouseX+mouseY)/4);
if (mouseX/2<=200){
shape="rectangle";
}else{
shape="ellipse";
}
}
void display(mouseX,mouseY){
stroke(c);
fill(c);
if(shape=="rectangle"){
rect(mouseX,mouseY,10,10);
}else if(shape=="ellipse"){
ellipse(mouseX,mouseY,10,10);
}
}
}
```
Can anyone explain this? I thought I followed the tutorial pretty well. Error occurs within the class, at
```auto
Person(){
```
---
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 5:01am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/2 "2019-12-10T05:01:23Z")
Sorry about the indenting, I’m new. How do I get it to show the correct indentation?
---
### Author:  [@Lexyth](https://discourse.processing.org/u/Lexyth)
#### Post date: [December 10, 2019, 5:13am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/3 "2019-12-10T05:13:30Z")
You can use the \ sign at the top when posting/editing.
As for the error, that generally means you are missing a } or you have too many {. Though you should have gotten a line number with that error Message i think…
Nevermind, you forgot a ; in void display() after drawing the rect.
---
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 7:09am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/4 "2019-12-10T07:09:10Z")
Damn semicolons! Still didn’t fix the error though.
---
### Author:  [@kll](https://discourse.processing.org/u/kll)
#### Post date: [December 10, 2019, 7:32am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/5 "2019-12-10T07:32:07Z")
```auto
Person joe;
void setup() {
size(500, 500);
joe = new Person();
}
void draw() {
background(200, 200, 0);
joe.display();
}
class Person {
String shape;
color c;
int w = 30;
Person() {
}
void display() {
c = color((mouseX+mouseY)/4, 0, 200);
if (mouseX <= width/2) shape="rectangle";
else shape="ellipse";
stroke(c);
fill(c);
if ( shape.equals("rectangle") ) rect(mouseX, mouseY, w, w);
else if ( shape.equals("ellipse") ) ellipse(mouseX, mouseY, w, w);
}
}
```
from this working version, you please read back / compare to your original
and see some small changes.
[https://processing.org/reference/class.html](https://processing.org/reference/class.html)
[https://processing.org/reference/String\_equals\_.html](https://processing.org/reference/String_equals_.html)
you can not just write a class free style,
better start from a working example and change line by line to your target function
one main point is to know that that part of a class
```auto
Person() {
}
```
works like a setup at creation,
there can ?predefine? may things…
but not use dynamic data like mouseX…
---
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 7:40am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/6 "2019-12-10T07:40:11Z")
@kll copy-pasted your code into my IDE, same result. Beginning to suspect a bug? Will try restarting IDE.
---
### Author:  [@kll](https://discourse.processing.org/u/kll)
#### Post date: [December 10, 2019, 7:46am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/7 "2019-12-10T07:46:58Z")
> [@hamp](#):
>
> same result.
please post a picture of the full PDE window to see the error after start
---
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 7:48am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/8 "2019-12-10T07:48:59Z")
@kll
---
### Author:  [@kll](https://discourse.processing.org/u/kll)
#### Post date: [December 10, 2019, 7:53am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/9 "2019-12-10T07:53:14Z")
you not copy my full code!!!
please try again ( copy / paste ) into a new PDE window
---
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 8:14am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/10 "2019-12-10T08:14:10Z")
@kll Same result.
---
### Author:  [@kll](https://discourse.processing.org/u/kll)
#### Post date: [December 10, 2019, 8:15am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/11 "2019-12-10T08:15:47Z")
this is not my code, why you not open new window and paste my code
instead try repair your code without knowing what lines are wrong ( 14 )
---
### Author:  [@hamp](https://discourse.processing.org/u/hamp)
#### Post date: [December 10, 2019, 8:25am UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/12 "2019-12-10T08:25:37Z")
@kll Sorry, new to processing, that works now. Thanks! (Still struggling to find the effective difference)
---
### Author:  [@jeremydouglass](https://discourse.processing.org/u/jeremydouglass)
#### Post date: [December 16, 2019, 11:55pm UTC](https://discourse.processing.org/t/class-constructor-block-not-working/16282/13 "2019-12-16T23:55:34Z")
> [@hamp](#):
>
> Still struggling to find the effective difference
Well, there are a _lot_ of changes here, and it can be difficult to understand when they aren’t presented one at a time.
As a general strategy, you can use any programming text editor that shows `diff` to look at the differences between the two. It adds a + in front of added lines and - in front of removed lines.
Diffs can still be hard to read if lots of whitespace changes have been made, so I manipulated things slightly to line them up so you could more easily see some of the things going on in the changes:
```diff
Person joe;
void setup() {
size(500, 500);
- background(0);
- Person joe = new Person();
+ joe = new Person();
}
void draw() {
+ background(200, 200, 0);
joe.display();
}
```
Okay, move your background command into draw, so that it clears the screen every frame for redrawing. Also, in setup **assign** `joe` as the global variable – don’t **declare** a new local variable `Person joe`, which only exists inside setup.
```diff
-Class Person(){
+class Person {
String shape;
color c;
+ int w = 30;
```
Next, declare a class with the `class` keyword – lowercase, `Class` isn’t a thing. Classes also don’t take method arguments, instead have constructors, so drop the (). Add `w` as a class object variable – this will mean that objects aren’t hard-coded to 10, their size can be changed.
```diff
- Person(){
- c=color((mouseX+mouseY)/4);
- if (mouseX/2<=200){
- shape="rectangle";
- }else{
- shape="ellipse";
- }
+ Person() {
}
- void display(mouseX,mouseY){
+ void display() {
+ c = color((mouseX+mouseY)/4, 0, 200);
+ if (mouseX <= width/2) shape="rectangle";
+ else shape="ellipse";
stroke(c);
fill(c);
```
Move all that stuff from the constructor into the display method. mouseX and mouseY are already global variable in Processing, so you don’t _need_ to pass them in, you can just use them.
```diff
- if(shape=="rectangle"){
- rect(mouseX,mouseY,10,10);
+ if(shape.equals("rectangle")){
+ rect(mouseX,mouseY,w,w);
- }else if(shape=="ellipse"){
- ellipse(mouseX,mouseY,10,10);
+ } else if(shape.equals("ellipse")){
+ ellipse(mouseX,mouseY,w,w);
}
}
}
```
Express dimensions in terms of w, not hard-coded with 10. Also, check string equality `.equals()` – don’t use ==.