This chapter explores how Java handles and organizes data. You'll learn about Java's basic data types and structures, including how to use simple Java objects, called POJOs (Plain Old Java Objects). We'll also cover wrapper classes, which let you use primitive data types as objects. Finally, you'll see how Java groups related classes into packages.

Plain Old Java Objects (POJO)

Defining a POJO

Using a POJO

POJO Rules

Wrapper classes

Wrapper class facts

Using Wrappers

Wrappers with null

Using packages

Using math classes

POJO, wrappers and java.math

Advanced Java Types

Java’s Collections Framework gives you ready-to-use data structures for working with groups of objects. In this chapter, you’ll learn how to use Lists, Sets, Maps, and Queues to organize and manage data in different ways.

Collections Framework Data Structures

About Collections

Setting up a Collection

Lists

Working with ArrayList

Working with LinkedList

Autoboxing and foreach

Sets, Queues

Working with HashSet

Working with Queue

Maps

Options

List

Choosing data structure

Working with HashMap

Using Collections and Arrays

Collections Framework

In this chapter, you'll learn how Java handles problems using exception handling. You'll use try/catch blocks to deal with errors, throw exceptions when needed, and add logging to track what your application is doing.

Try and Catch

Try-catch

Finally

Using finally in a real example

Exception object

Errors and Exceptions

Fixing an error

RuntimeException

Checked exception

Throwing

Throws

(Re)Throwing

Logging

Logging APIs

Wrap Up

Exception Handling

Build a strong foundation in Java by learning how it manages and structures data, handles collections, and deals with errors - all essential skills for any developer. You'll start with Plain Old Java Objects (POJOs) and wrapper classes to model and work with data effectively. Next, you'll explore the Collections Framework - Java's built-in library for organizing objects using Lists, Sets, Maps, and Queues. Finally, you'll master Java's exception handling and logging tools to write more robust, maintainable code.

Java is a powerful, widely used programming language, and understanding how it handles data is essential for writing clean, effective code. This course gives you a practical introduction to Java’s data modeling, collections, and error-handling tools.<br><br><h2>Work with POJOs and Organize Code</h2>Start by learning how to model data using Plain Old Java Objects (POJOs) and wrapper classes. You'll also explore how Java uses packages to group related classes and keep code organized.<br><br><h2>Use the Collections Framework</h2>Get to know Java’s built-in data structures—Lists, Sets, Maps, and Queues—and learn how to use them to store and manage groups of objects in different ways.<br><br><h2>Handle Errors and Log Application Behavior</h2>Wrap up by learning to handle exceptions using try/catch blocks and throw custom errors when needed. You’ll also add logging to your code to track and understand your program’s behavior.
By the end, you’ll be able to structure data, work with Java collections, and write more reliable, maintainable applications.

Introduction to Object-Oriented Programming in Java

Learn to work with Plain Old Java Objects, master the Collections Framework, and handle exceptions like a pro, with logging to back it all up!

Data Types and Exceptions in Java

Java-Grundlagen

Ordered, indexed collection of objects allowing duplicates that perform better at adding/removing elements

Unordered, unindexed collection of objects that guarantees the uniqueness of its elements

Key/value pairs of objects in a lookup table. Values allow for duplicates and null. Keys cannot be duplicates or null.

Choosing data structure

Data Types and Exceptions in Java

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