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How to use assertions in Java

Use Java assertions to document program correctness and more quickly test and debug your programs

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How to describe Java code with annotations

Use annotations to associate metadata with application elements in your Java programs

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Packages and static imports in Java

Use packages and static imports to organize top-level types and simplify access to their static members

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Static classes and inner classes in Java

Learn how to use the four types of nested classes in your Java code

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Nesting with Java interfaces

Learn three ways to use nesting techniques with Java classes and interfaces

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Installing Oracle Java SE 11 on Ubuntu 18.04

A quick installation guide for Ubuntu Linux users installing Java 11

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How to store data in Java objects

A timely introduction to using instance variables in your Java classes

Javaworld > JVM / JDK / JRE explainer series > Java Development Kit > write your code

What is the JDK? Introduction to the Java Development Kit

The JDK is a key platform component for building Java applications. At its heart is the Java compiler

Javaworld > JVM / JDK / JRE explainer series > Java Runtime Environment > monitoring + configuration

What is the JRE? Introduction to the Java Runtime Environment

The JRE creates the JVM and ensures dependencies are available to your Java programs. It also plays a vital role in devops and cloud configurations

Javaworld > JVM / JDK / JRE explainer series > Java Virtual Machine > debug + optimize

What is the JVM? Introducing the Java Virtual Machine

The Java Virtual Machine manages system memory and provides a portable execution environment for Java-based applications. Developers reap the rewards in performance, stability, and predictable runtimes.

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Socket programming in Java: A tutorial

Three iterations of a Java socket client-server example demonstrate the timeless utility of Java I/O

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Inheritance versus composition: How to choose

Compare two fundamental ways to relate classes, then practice debugging ClassCastExceptions in Java inheritance

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Does Java pass by reference or pass by value?

You've probably heard before that Java passes by value, but what matters is how well you understand the concept and the code. In this Java Challenger, find out what happens when you pass an object reference to a method in Java

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Exceptions in Java, Part 2: Advanced features and types

Take your Java exceptions to the next level with stack traces, exception chaining, try-with-resources, final re-throw, and more

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Exceptions in Java, Part 1: Exception handling basics

Everything you need to know about throwing, trying, catching, and cleaning up after Java exceptions

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Comparing Java objects with equals() and hashcode()

What is the contract between equals() and hashcode()? Learn how these methods work together when comparing Java objects

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Polymorphism and inheritance in Java

Challenge yourself, with this brain-teasing introduction to Java method invocation in polymorphic method calls

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Thread behavior in the JVM

The JVM does what it wants to do, so how can you predict the order of thread execution?

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