Java not running .class files

I rebooted my computer, and now whenever I type
java <filename> it responds with:
C:\Development\Java\Projects\Scratch>java T1
Exception in thread "main" java.lang.NoClassDefFoundError: T1
However, it compiles fine:
class foo {
class T1 {
    public static void main (String [] args) {
        foo [] fooArray = new foo[5];
        if (fooArray[1] instanceof Object)
          System.out.println("fooArray[1] is an object");
        if (fooArray[1] instanceof foo)
          System.out.println("fooArray[1] is a foo");
}What am I missing to get it to run with java T1?
(every other class file that used to work behaves the same way)

Yes, it is the classpath. Strangely . is in my classpath in the environment settings in the control panel. I guess I can survive adding -cp . but it is kind of a pain in the a__ for no reason I can discern

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Theophilus Mah

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