NoClassDefFoundError in Package - package

Question

I'm having an issue with NoClassDefFoundError when running Java from the Windows Command Prompt. I put the main TestLogger.java file in C:\mywork and four other java files in C:\mywork\logging that were organized as a package.
There was no difficulty compiling these files (javac TestLogger.java), or even creating a jar file, but I failed when trying to run the compiled TestLogger, and got the "Exception in thread 'main' java.lang.NoClassDefFoundError".
I also did some searching on the web, and found that most folks who were getting this error were only trying to run a single simple HelloWorld program. So I tried my own HelloWorld.java in C:\mywork and weird enough, there was no problem compiling and running it. And none of the various solutions I found on the web such as checking the environment variable, and adding a period after -classpath parameter, could work a miracle in my case.
I'm using JDK 1.7 on Windows XP. I'm sure there's nothing wrong with the environment variables. Below are the full contents of my source files (an example from Jeff Friesen's 2nd Edition of Learn Java for Android Development, p. 175). Hopefully someone can shed some light on this. Thanks in advance!
In C:\mywork I have one single file as the main entrance.
TestLogger.java:
package logging;
import logging.Logger;
import logging.LoggerFactory;
public class TestLogger {
public static void main(String[] args) {
Logger logger = LoggerFactory.newLogger(LoggerFactory.CONSOLE);
if (logger.connect()) {
logger.log("test message #1");
logger.disconnect();
}
else
System.out.println("cannot connect to console-based logger");
logger = LoggerFactory.newLogger(LoggerFactory.FILE, "x.txt");
if (logger.connect()) {
logger.log("test message #2");
logger.disconnect();
}
else
System.out.println("cannot connect to file-based logger");
logger = LoggerFactory.newLogger(LoggerFactory.FILE);
if (logger.connect()) {
logger.log("test message #3");
logger.disconnect();
}
else
System.out.println("cannot connect to file-based logger");
}
}
In the C:\mywork\logging folder I have four files:
1) Logger.java:
package logging;
public interface Logger {
boolean connect();
boolean disconnect();
boolean log(String msg);
}
2) Console.java:
package logging;
public class Console implements Logger {
private String dstName;
Console(String dstName) {
this.dstName = dstName;
}
#Override
public boolean connect() {
return true;
}
#Override
public boolean disconnect() {
return true;
}
#Override
public boolean log(String msg) {
System.out.println(msg);
return true;
}
}
3) File.java:
package logging;
public class File implements Logger {
private String dstName;
File(String dstName) {
this.dstName = dstName;
}
#Override
public boolean connect() {
if (dstName == null)
return false;
System.out.println("opening file " + dstName);
return true;
}
#Override
public boolean disconnect() {
if (dstName == null)
return false;
System.out.println("closing file " + dstName);
return true;
}
#Override
public boolean log(String msg) {
if (dstName == null)
return false;
System.out.println("writing "+msg+" to file " + dstName);
return true;
}
}
4) LoggingFactory.java:
package logging;
public abstract class LoggerFactory {
public final static int CONSOLE = 0;
public final static int FILE = 1;
public static Logger newLogger(int dstType, String... dstName) {
switch (dstType) {
case CONSOLE:
return new Console(dstName.length == 0 ? null : dstName[0]);
case FILE:
return new File(dstName.length == 0 ? null : dstName[0]);
default:
return null;
}
}
}