A ClassFile object stores information about a Java class. The class may
be read from a DataInputStream.and written to a DataOutputStream. These
are usually streams from a Java class file or a class file component of a
Jar file.
Read the class from a data stream. This method takes an InputStream
as input and parses the class from the stream.
Parameters: stream - an InputStream from which the class will be read exception: IOException - if there is a problem reading from the givenstream. exception: ClassFormatError - if the class cannot be parsed correctly