@Override
  public Class<?> loadClass(String name) throws ClassNotFoundException {
    return loadClass(name, null);
  }
Get a CoprocessorClassLoader for a coprocessor jar path from cache. If not in cache, create
one.
@param path       the path to the coprocessor jar file to load classes from
@param parent     the parent class loader for exempted classes
@param pathPrefix a prefix used in temp path name to store the jar file locally
@param conf       the configuration used to create the class loader, if needed
@return a CoprocessorClassLoader for the coprocessor jar path
hbase-common/src/main/java/org/apache/hadoop/hbase/util/CoprocessorClassLoader.java