Java HotSpot Virtual Machine

I have been trying to run the following program

import java.io.IOException;

import org.apache.bcel.classfile.ClassParser;
import org.apache.bcel.classfile.ConstantPool;
import org.apache.bcel.classfile.JavaClass;

public class BCELTest {

	public static void main(String[] args) {
		try {
			ClassParser parser = new ClassParser("HelloWorld.class");
			JavaClass jClass = parser.parse();
			//jClass.dump(System.out);
			System.out.println(jClass.toString());
			
			ConstantPool cPool = jClass.getConstantPool();
			System.out.println("****Constant Pool****");
			System.out.println(cPool.toString());
			
		} catch(IOException ioEx) {
			ioEx.printStackTrace();
		}
		
	}
}

I am recieving a number of errors when attempting to compile this program. The packages are not recognised, I have set my CLASSPATH to bcel.jar but I am still recieving the errors, would anybody have any idea how I could solve this problem?