public static void setContextClassLoader(ClassLoader loader) {
        CONTEXT_CLASS_LOADER = loader;
    }
Sets the context class loader to use for all threads that access
this class. Used for example in an OSGi environment to avoid problems
with the default context class loader.

@param loader default context class loader,
              or <code>null</code> to automatically pick the loader
tika-core/src/main/java/org/apache/tika/config/ServiceLoader.java