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String comparisons in Java

How Java's String methods, keywords, and operators process comparisons in the String pool

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Sorting with Comparable and Comparator in Java

Comparable or Comparator? Choose the correct interface for the sorting algorithm you need

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Method overloading in the JVM

Test your mind with the first Java Challenger in a new series. Can you outthink the Java virtual machine?

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What is EJB? The evolution of Enterprise JavaBeans

Java's server-side platform for developing distributed business applications

Interfaces in Java

Interfaces in Java

Learn the difference between classes and interfaces once and for all, then get started declaring, implementing, and extending interfaces in your Java programs

Java 101: Class and object initialization

Class and object initialization in Java

Learn how to to initialize Java classes and objects for successful JVM execution

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Java polymorphism and its types

Learn the four types of polymorphism in Java, then start using subtype polymorphism to execute different forms of the same Java method

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Java tip: Fields and methods in Java

Learn seven advanced techniques for working with fields and methods in Java, including recursion, method call chaining, pass-by-value arguments, and rules for calling methods

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When to use composition vs inheritance

Inheritance is a valuable programming technique, but in some conditions it breaks encapsulation. Find out why composition is the vital alternative to inheritance, and learn when and how to use it in your Java programs.

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Inheritance in Java, Part 2: Object and its methods

Get to know Java's Object superclass and its methods for duplicating, comparing, cleaning up, and scheduling Java objects

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Inheritance in Java, Part 1: The extends keyword

Use Java's extends keyword to derive a child class from a parent class, invoke parent class constructors and methods, override methods, and more

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Classes and objects in Java

Learn how to make classes, fields, methods, constructors, and objects work together in your Java applications.

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Loop, switch, or take a break? Deciding and iterating with Java statements

Learn how to use standby statements like for, while, if-else, and break, then get started with the new switch expressions in Java 12

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Evaluate Java expressions with operators

Everything you need to know about the Java operator types and using them to write and evaluate Java expressions in Java 12

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Elementary Java language features

Learn three ways to document your code, then get started using identifiers, types, literals, and variables in Java 12

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Learn Java from the ground up

If you're new to Java then you've come to the right place. Get an overview of the Java platform, then code your first application using Java 12 and the new Java Shell

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What is JPA? Introduction to the Java Persistence API

Get to know the Java ORM standard for storing, accessing, and managing Java objects in a relational database

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Java XML and JSON: Document processing for Java SE, Part 2: JSON-B

Use the Java API for JSON Binding (JSON-B) to serialize and deserialize Java objects, arrays, and collections in Java SE

Javaworld > JVM / JDK / JRE explainer series

JVM, JDK, JRE: What's the difference?

Three indispensable Java platform components, and how they work together in your Java applications

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Java XML and JSON: Document processing for Java SE, Part 1: SAXON and Jackson

Learn how to transform and convert XML and JSON documents with SAXON and Jackson

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