Java Help

[DevilMayCry42]

So....I decided that I should learn Java, just to get one programming language under my belt (hopefully) before I leave college. Great. I went to this site:
"Hello World!" for Microsoft Windows (The Java™ Tutorials > Getting Started > The "Hello World!" Application)
and followed the guide. I installed the JDK, and then followed the instructions....
When it gets to the part where you have to open command prompt, I do it all and then type in 'javac HelloWorldApp.java' and it says "javac is not recognised as an internal or external command....."

Does anyone have any idea what could be wrong?
I uninstalled the JDK from my D drive, and put it in the default folder on C just to see if that works but same problem. I rebooted after both installs and the problem still persists...I'm guessing its something simple, but i just can't see it!

[streetster]

you need to have the java 'bin' directory in your path...

to do this:

Right-click 'My Computer -> properties -> 'advanced' tab -> Environment Variables -> double-click Path

and add:

c:\program files\[path to jdk here]\bin;

to the end of it.

(eg mine is: C:\Program Files\Java\jdk1.6.0\bin)

then open up a new command prompt and it should work

[DevilMayCry42]

I get the the environment variables and I dont see "Path" to double click...

Oh this is strange, I feel like one of the people here at college that I usually help out - They have no clue aswell!

[streetster]

[DevilMayCry42]

Right. I'm gonna uninstall it agian, and put it back onto my D drive (software) and then see what to do from there

EDIT:

nevermind, i cant be arsed to move it, I found "path". Thanks a bunch, i'll see if it works now!

[streetster]

do you not have 'Path' in system variables? If not, add a new one

[DevilMayCry42]

Yaaay, thanks streetster, It works....



now i get

HelloWorldApp.java:7: cannot find symbol
symbol : method prongIn<java.lang.String>
location: class java.io.PrintStream
System.out.pringIn <"Hello World!:>;//Display the sring.

1 error

[streetster]

cos its not:

System.out.pringIn

its

System.out.println("hello world");

(P R I N T L N)

[DevilMayCry42]

It's coz the 'g' is next to the 't'!!!

Ok, i re-typed it, and now it seems to work. Thanks for all the help Streetster

[streetster]

You're welcome, happy java-ing

[DevilMayCry42]

That site is really confusing...
I know its a long shot, as most of you probably took CS at uni, but do any of you know of any good begginer sites? I know (pretty much) nothing of programming at all (i stared with VB a few years ago, but stopped after about 2 months and never picked it up again)....

Any help is appreciated

[streetster]

What problems are you having in particular?

We had a few java modules at uni, and the rest i just googled to work out how stuff is done

[DevilMayCry42]

This page

Lesson: A Closer Look at the "Hello World!" Application (The Java™ Tutorials > Getting Started)

Maybe I'm just tired, but it isn't making much sense....

I'll look at it again tomorow after school, see if it makes more sense.

I think it was sometime around here:
"The keyword class begins the class definition for a class named name, and the code for each class appears between the opening and closing curly braces marked in bold above. Chapter 2 provides an overview of classes in general, and Chapter 4 discusses classes in detail. For now it is enough to know that every application begins with a class definition." That I just went and decided to look again tomorow

I am going to hit the bed now, as it is quite late out here.
Please do help, I'll be back tomorow....

[streetster]

A way to think of java classes and methods is that it is a way of modelling something in the real world...

Classes have attributes which are variables (int/string/array/other even classes) and methods which are a way of 'doing' something to the class...

In order to 'use' a class, you have to instantiate it, and then you get an object... and a Class just has all the bits of stuff about the thing you want to model.

methods look like:

public void doSomething(String s) {

System.out.println("string:" + s);

}

the 'void' means that nothing is being returned... you can pass a method some variable, and perform an action on that variable and then return the modified variable out again..


hmm i've mostly just waffled..

[DevilMayCry42]

A way to think of java classes and methods is that it is a way of modelling something in the real world...

Classes have attributes which are variables (int/string/array/other even classes) and methods which are a way of 'doing' something to the class...

In order to 'use' a class, you have to instantiate it, and then you get an object... and a Class just has all the bits of stuff about the thing you want to model.

methods look like:

public void doSomething(String s) {

System.out.println("string:" + s);

}

the 'void' means that nothing is being returned... you can pass a method some variable, and perform an action on that variable and then return the modified variable out again..


hmm i've mostly just waffled..

[streetster]

just get stuck in, you'll figure it out