Java

Java is a statically typed, object-oriented language that compiles to bytecode and runs on the Java Virtual Machine, so the same build runs on any platform with a JVM. Its mature ecosystem includes the Collections framework, JDBC, JPA with Hibernate for data access and Spring Boot for web services. Java remains a mainstay for enterprise backends and large data systems, with a new long-term support release every two years.

74 articles

28/05/2023 11 min read

Utility Classes: Objects, Math, Random, and UUID

Executive Summary: The JDK’s utility classes cover null-safe checks, exact math, random numbers, and IDs. I’ll walk through…
07/05/2023 11 min read

Date and Time API in Java (java.time)

Executive Summary: The java.time API separates human dates from machine timestamps. I’ll cover LocalDate and LocalDateTime for calendar…
01/04/2023 10 min read

Optional in Java: Avoiding NullPointerException

Executive Summary: Optional in Java is a container that is either present or empty, meant for query results…
05/03/2023 10 min read

Streams API Part 3: Parallel Streams and Pitfalls

Executive Summary: Parallel streams split work across the shared ForkJoinPool, and they only help under specific conditions. I…
04/02/2023 10 min read

Streams API Part 2: reduce, collect, and Collectors

Executive Summary: Java streams end in a value through reduce or collect. I cover reduce with an identity…
07/01/2023 9 min read

Streams API Part 1: map, filter, and forEach

Executive Summary: A Java stream is a one-use, lazy pipeline over a source such as a collection, array,…
10/12/2022 10 min read

Lambda Expressions and Functional Interfaces in Java

Executive Summary: A Java lambda implements the single abstract method of a functional interface. I cover the standard…
19/11/2022 9 min read

Creating Custom Exceptions and Best Practices

Executive Summary: Create a custom Java exception when a failure has domain meaning that callers need to handle…
16/10/2022 10 min read

The Java Exception Hierarchy: Checked, Unchecked, and Error Handling by Design

Executive Summary: Every Java exception descends from Throwable, split into Errors, checked exceptions, and unchecked RuntimeExceptions. I cover…
18/09/2022 11 min read

Generics in Java: Type Safety, Bounded Types, and Wildcards

Executive Summary: Java generics give you type-safe, reusable code with no casts. Here I cover generic classes and…
14/08/2022 8 min read

Choosing the Right Collection: Performance and Trade-offs

Executive Summary: Choosing a Java collection comes down to access pattern, ordering needs, key types, and data size.…
10/07/2022 10 min read

Collections Framework Part 2: Map and Queue

Executive Summary: Java Maps store values by unique keys and Queues control processing order. I cover HashMap, LinkedHashMap,…
11/06/2022 11 min read

Collections Framework Part 1: List and Set

Executive Summary: The Collections Framework separates interfaces like List and Set from their implementations. I explain when to…
22/05/2022 13 min read

Practice: Model a Library System with OOP (Part 2: Behavior and Persistence)

Executive Summary: Part 2 of the library system project adds behavior and persistence to the Java domain model.…