Called for every class name that is needed but has not yet been
defined by this classloader or one of its parents. It is called by
loadClass()
after both
findLoadedClass()
and
parent.loadClass()
couldn't provide the requested class.
The default implementation throws a
ClassNotFoundException
. Subclasses should override this
method. An implementation of this method in a subclass should get the
class bytes of the class (if it can find them), if the package of the
requested class doesn't exist it should define the package and finally
it should call define the actual class. It does not have to resolve the
class. It should look something like the following:
// Get the bytes that describe the requested class
byte[] classBytes = classLoaderSpecificWayToFindClassBytes(name);
// Get the package name
int lastDot = name.lastIndexOf('.');
if (lastDot != -1)
{
String packageName = name.substring(0, lastDot);
// Look if the package already exists
if (getPackage(packageName) == null)
{
// define the package
definePackage(packageName, ...);
}
}
// Define and return the class
return defineClass(name, classBytes, 0, classBytes.length);
loadClass()
makes sure that the
Class
returned by
findClass()
will later be returned by
findLoadedClass()
when the same class name is requested.