public void setExtension(String name, Class clazz) {
        Class previousClass = siddhiContext.getSiddhiExtensions().put(name, clazz);
        if (previousClass != null) {
            log.warn("Dropping extension '" + previousClass + "' as '" + clazz + "' is " +
                    "loaded with the same namespace and name '" + name + "'");
        }
    }
Method used to register extensions to the Siddhi Manager. But extension classes should be present in classpath.

@param name  Name of the extension as mentioned in the annotation.
@param clazz Class name of the implementation
modules/siddhi-core/src/main/java/io/siddhi/core/SiddhiManager.java