Using defineClass to Dynamically Create Class from Bytes

Question

It seems like I should be able to do this with a class loader derived from URLClassLoader that includes a loadClass():

public Class loadClass(String className, byte[] classBytes)
throws ClassNotFoundException, NoClassDefFoundError
{
    Class result = null;

    result = defineClass(className, classBytes, 0, classBytes.length);
    classes.put(className, result);
    return result;
}

Then I read bytes from a class file and call the above loadClass method. I get this:

java.lang.NoClassDefFoundError: com/samples/SampleClass (wrong name: com/samples/SampleClass) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631) at java.lang.ClassLoader.defineClass(ClassLoader.java:615) at java.lang.ClassLoader.defineClass(ClassLoader.java:465)

The odd thing is that the name and the "wrong name" are the same. And both are the correct package.

How is it possible to get NoClassDefFoundError with the correct expected name? And is it possible to do this defineClass?

Using the deprecated form, without the classname, works perfectly:

result = defineClass(classBytes, 0, classBytes.length);

Thanks

Answer 1

javadoc: Parameters: name - The expected name of the class, or null if not known, using '.' and not '/' as the separator and without a trailing ".class" suffix.

try replace "/" to "."