Manually load .class outside package?

Question

I am trying to use this example:
http://tutorials.jenkov.com/java-reflection/dynamic-class-loading-reloading.html
to load some class files outside a package.
public class MainClass {
  public static void main(String[] args){
    ClassLoader classLoader = MainClass.class.getClassLoader();
    try {
        Class aClass = classLoader.loadClass("com.jenkov.MyClass");
        System.out.println("aClass.getName() = " + aClass.getName());
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
}But that only seem to work for classes in a package. If I do:
    ClassLoader classLoader = MainClass.class.getClassLoader();
    String classPath = C://test//IOUtil.class
    try {
        Class aClass = classLoader.loadClass(classPath);
        System.out.println("aClass.getName() = " + aClass.getName());
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
...I get the exception:
java.lang.ClassNotFoundException: C:/test/IOUtil.class
In the API:
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/ClassLoader.html#name
it says:
Any class name provided as a String parameter to methods in ClassLoader must be a binary name as defined by the Java Language Specification.
Examples of valid class names include:
"java.lang.String"
"javax.swing.JSpinner$DefaultEditor"
"java.security.KeyStore$Builder$FileBuilder$1"
"java.net.URLClassLoader$3$1"
I assume the error occurs because I don't supply a 'binary name'. But how do I specify a binary name for a local .class file on my disk?

Answer 1

fedevaps wrote:
Hm not sure I understand, I have now tried to replace:
String classPath = "C://test//IOUtil.class"With:
String classPath = "C.test.IOUtil.class"
String classPath = "C.test.IOUtil"
String classPath = "test.IOUtil"All gives the same error. Do you mean that I need to add c:\test to my classpath before trying to load the class?
I Assume that I need to tell the compiler where to look for the .class file, since its not located in any package and is also outside my classpath.
Edited by: fedevaps on Jun 16, 2009 5:54 PM
Edited by: fedevaps on Jun 16, 2009 6:04 PMThe thing you give the ClassLoader is a proper class name. Since IOUtil is in the default package the proper class name (I think, since I've never used the default package) is "IOUtil".
Now, if the directory it sits in is not in your class path I'm not sure you can get the ClassLoader to load it. Maybe you can, but I wouldn't know.