Introducing full-stack Internet architecture technologies centered on Java
This tutorial explains the Observer design pattern with a Java implementation using an e-commerce order system where payment triggers logistics and procurement updates, demonstrating loose coupling between subject and observers.
This article explains the Chain of Responsibility design pattern with a practical Java example of a leave approval workflow, showing how it decouples request senders from receivers and enables flexible, extensible handling through a chain of handlers.
This article explains binary tree representation in Java and demonstrates recursive pre-order, in-order, post-order, and iterative level-order traversals, plus methods to create a full binary tree, count nodes, compute height, and count leaf nodes with complete runnable code.
This article introduces Apache Kafka as a distributed streaming platform, detailing its core advantages—high throughput via sequential writes and zero-copy, horizontal scalability through partitions, durability with 7-day retention and replication—and key use cases including log aggregation, event-driven architectures, real-time analytics, and big data integration with tools like Flink and Spark Streaming.
This article introduces Apache ZooKeeper as a distributed coordination service, explains its hierarchical data model with four znode types (persistent, persistent sequential, ephemeral, ephemeral sequential), describes the watch mechanism for change notifications, and provides a step-by-step installation and basic CLI tutorial for version 3.8.3.
This article introduces MongoDB as an open-source document database, explains NoSQL categories, details MongoDB's data model (fields, documents, collections, databases) with relational database analogies, and provides step-by-step installation instructions for MongoDB 7.0 on CentOS 7 via yum and manual RPM.
This article explains MySQL deadlocks with a concrete example of two transactions updating rows in opposite order, demonstrates deadlock detection via SHOW ENGINE INNODB STATUS, and lists prevention techniques including small transactions, proper isolation levels, lock wait timeouts, consistent operation order, and indexing.
The article shows a Java if-else chain that applies different discounts and actions based on user type, then asks which design pattern can refactor it into more elegant code.
This tutorial explains MySQL table joins—including inner, left, right, full outer, and exclusion joins—using Venn diagrams, sample tables, and SQL queries to illustrate each join type's result set.
An experienced interviewer shares six practical strategies for software developers to boost interview success rates, covering company research, resume optimization, systematic project understanding, soft skills, referrals, and industry trend awareness.
