Understanding Casting with Generics

With multiple level inheritance and polymorphism it can become a bit challenging to see how a method accepting and returning a generic would behave if within the method some transformation takes place and either a sub or super type of that generic is returned. Let's take an example Interface: public interface ClassInterface { String sayHello(); … Continue reading Understanding Casting with Generics

JSP hot-deploy in Wildfly

To enable hot-deploy of JSPs in Wildfly, i.e. to automatically publish any changes to JSPs in ${WILDFLY_ROOT}/standalone/tmp/vfs/temp/tempxxxxxxx/content-xxxxxxx without requiring redeployment of war, set the development attribute of jsp-config within undertow subsystem to true as below: <subsystem xmlns="urn:jboss:domain:undertow:3.0"> <servlet-container name="default" default-encoding="UTF-8">         <jsp-config development="true" tag-pooling="false"/>         <websockets/> </servlet-container>  

Ohioedge Workflow: Workflow-item scheduling, routing, assignment and execution

Assigner assigns a mechanism (user or bot) to work on a workflow-item available at a workflow-station. Performer/Executor completes the bot tasks. Scheduler creates a schedule for completed workflow-item. The schedule consists of which workflow-station the workflow-item should go to next and at what time. Router creates workflow-item processing tasks at workflow-stations per the schedules.  

Ohioedge Workflow: Loading and processing of workflow items

Any resource with a status of not-available:{stateID} is picked up by the workflow engine loader and added into the workflow as a workflow-item. The loader is composed of two parts - producer and consumer. The loader-producer updates the status of resource to loading-in-process:{stateID} and puts the resource identifier in kafka. Loader-consumers are running on all … Continue reading Ohioedge Workflow: Loading and processing of workflow items

Cassandra node vs partition: A simple explanation

As explained in How does Cassandra store data? – A simple explanation Cassandra uses partitioning key (the first part of primary key) to store a record into a partition on a node. Prior to version 1.2, one server = one node. That is each machine was assigned to a range of values, so that the entire cluster covered … Continue reading Cassandra node vs partition: A simple explanation