Cannot run Java program in command window

[tricky]

When I try to run a simple program, even HelloWorld.java, the java file opens in NotePad and nothing happens in the command window. Below is one of the programs I tried to run which was copied from a training book.

/*
* SimpleMathTest
* Performs simple mathematical operations on integer and
* double operands
*/

public class SimpleMathTest {

public static void main(String args[]) {
int x = 10,
y = 7;
//be careful not to confuse math operators with string
//operators
System.out.println(x + " + " + y + " = " + (x + y));
System.out.println(x + " - " + y + " = " + (x - y));
System.out.println(x + " * " + y + " = " + (x * y));
System.out.println(x + " / " + y + " = " + (x / y));
System.out.println(x + " % " + y + " = " + (x % y));

//would be more readable with explicit casting
//i.e. double a = (double) x, b = (double) y;
double a = x,
b = y;
System.out.println(a + " + " + b + " = " + (a + b));
System.out.println(a + " - " + b + " = " + (a - b));
System.out.println(a + " * " + b + " = " + (a * b));
System.out.println(a + " / " + b + " = " + (a / b));
System.out.println(a + " % " + b + " = " + (a % b));

//emphasizes that floating point modulus ops can
//result in real numbers
System.out.println("1.1 % 1.0 = " + (1.1 % 1.0));
}
}

[sunde887]

What exactly do you type on the cmd?

[tricky]

I type: SimpleMathTest.java, which is what it is named. But even with HelloWorld.java the same thing happens. That is after setting up the environment which now appears as:

C:\Users\Phaeton\Documents\JAVA>SET PATH=C:\Windows\system32;C:\Windows;C:\Windows\Sys tem32\Wbem;C:\jdk1.3.1\bin

[sunde887]

Try typing

java SimpleMathTest

Also, if you are using java 3 as that path implies, I'd suggest you update your java. Java is on 7 now as opposed to the 3 you seem to be using.

[tricky]

That was it. I thank you much. Take care...