JavaBeginner
Java Fundamentals
Learn the basics of the Java language
19 chapters72 lessons207 challenges
Course curriculum
Chapter 1: Variables, Types & Operators
- ▸Variables and primitive types
- ▸Reference types, String and null
- ▸Operators
- ▸Casting and conversions
Chapter 2: Control Flow
- ▸if / else
- ▸switch (classic and modern)
- ▸for and while loops
- ▸for-each, break and continue
Chapter 3: Strings
- ▸String and basic methods
- ▸Comparison: equals vs ==
- ▸StringBuilder
- ▸Formatting and text blocks
Chapter 4: Arrays
- ▸Declaring and accessing
- ▸Iterating arrays
- ▸Multidimensional arrays
- ▸The Arrays class and its limits
Chapter 5: Methods
- ▸Declaring a method
- ▸Pass by value
- ▸Overloading
- ▸static vs instance
Chapter 6: OOP: Classes & Objects
- ▸Classes and objects
- ▸Constructors and this
- ▸Encapsulation
- ▸toString and equals
Chapter 7: Inheritance & Polymorphism
- ▸extends and super
- ▸Override
- ▸Polymorphism
- ▸final and modifiers
Chapter 8: Interfaces & Abstract Classes
- ▸Interfaces
- ▸Abstract classes
- ▸Interface or abstract class?
- ▸Default methods
Chapter 9: Collections Framework
- ▸List and ArrayList
- ▸Set and HashSet
- ▸Map and HashMap
- ▸Iterating collections
Chapter 10: Generics
- ▸What generics are
- ▸Generic classes and methods
- ▸Bounds (bounded types)
- ▸Wildcards
Chapter 11: Exception Handling
- ▸try / catch
- ▸Checked vs unchecked
- ▸finally and try-with-resources
- ▸throw and throws
Chapter 12: Lambdas & Stream API
- ▸Lambdas and functional interfaces
- ▸Streams: map and filter
- ▸reduce and collect
- ▸Optional
Chapter 13: Concurrency
- ▸Threads and Runnable
- ▸Race conditions and synchronized
- ▸ExecutorService and thread pools
- ▸Safe concurrent tools
Chapter 14: JVM, Memory & GC
- ▸How the JVM works
- ▸Stack and Heap
- ▸The Garbage Collector
- ▸Common memory errors
Chapter 15: Modern Java (17-21)
- ▸Records
- ▸Sealed classes
- ▸Pattern matching and switch
- ▸Text blocks and var
Chapter 16: Design Patterns
- ▸What design patterns are
- ▸Singleton and Factory
- ▸Builder
- ▸Strategy and Observer
Chapter 17: Performance & Senior Best Practices
- ▸Complexity and data structures
- ▸StringBuilder vs concatenation
- ▸Streams, autoboxing and traps
- ▸Measure before optimizing
Chapter 18: Interview Topics
- ▸equals and hashCode
- ▸== vs equals, String pool
- ▸final, static and immutability
- ▸Frequent interview questions
Chapter 19: Final project: Contact book
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