macOS Beginning Java programmer 10.4

[jsprice2]

java beginner - OS 10.4 - using terminal and Head First Java text to self learn - old BASIC person from years ago -

get the following error:
Exception in thread "main" java.lang.NoClassDefFoundError: GoodDogTestDrive/class

code below - would also like to know how to run code with 2 classes - everything is in the same directory
-------------

class GoodDog {
private int size;

public int getSize() {
return size;
}
public void setSize(int s) {
size = s;
}
void bark() {
if (size > 60) {
System.out.println("Woof Woof !");
} else if (size > 14) {
System.out.println("Ruff Ruff!");
} else {
System.out.println("Yip Yip!");
}
}
}

class GoodDogTestDrive {
public static void main (String[ ] args) {
GoodDog one = new GoodDog();
one.setSize(70);

GoodDog two = new GoodDog();
two.setSize(8);

System.out.println("Dog one: " + one.getSize());
System.out.println("Dog two: " + two.getSize());

one.bark();
two.bark();
}
}

 

[lazydog]

Is your file named GoodDogTestDrive.java?

b e n

EDIT: I've put all the code you posted in a file called GoodDogTestDrive.java and it compiles and runs fine.

 

[cbougher]

I think GoodDogTestDrive needs to be declared public.

 

[ChrisBrightwell]

Don't include the ".class" in your java command.

For example, to build and run HelloWorld.java:

class HelloWorld
{
  public static void main (String args[])  
  {
    System.out.println("Hello, world!");
  }
}

Then in terminal, these are your commands:

% javac HelloWorld.java
% java -cp ./ HelloWorld

The problem with using "java HelloWorld.class" is that the . is a package/file separator, so it looks for ./HelloWorld/class.class ... which won't exist.

Also, the "-cp ./" is just to ensure that it looks in the local directory for the .class file to run. Some JVMs add automatically search there, but not all do, so it's usually a good practice to explicitly set the classpath.

Hope this helps.

 

[scan]

Don't include the ".class" in your java command.

For example, to build and run HelloWorld.java:

class HelloWorld
{
  public static void main (String args[])  
  {
    System.out.println("Hello, world!");
  }
}

Then in terminal, these are your commands:

% javac HelloWorld.java
% java -cp ./ HelloWorld

The problem with using "java HelloWorld.class" is that the . is a package/file separator, so it looks for ./HelloWorld/class.class ... which won't exist.

Also, the "-cp ./" is just to ensure that it looks in the local directory for the .class file to run. Some JVMs add automatically search there, but not all do, so it's usually a good practice to explicitly set the classpath.

Hope this helps.

exactly what he said. This is a common exception. If you run your program without the .class then its a classpath issue.

 

[jsprice2]

Beginning Java programmer 10.4

Thanks for alll the help. I did put .class at the end of command line and it was the problem.