Java Roadmap - Intermediate

Follow this step-by-step roadmap to master java at Intermediate level

1

Object-Oriented Programming (OOPs)

4 weeks

▹Classes & Objects
▹Constructors & Constructor Overloading
▹The `this` & `super` keywords
▹Pillars of OOP: Encapsulation (Getters/Setters, Access Modifiers)
▹Pillars of OOP: Inheritance (single, multilevel, hierarchical)
▹Pillars of OOP: Polymorphism (Method Overloading & Overriding)
▹Pillars of OOP: Abstraction (Abstract Classes & Methods)
▹The `final` keyword (for variables, methods, classes)
▹Interfaces & `implements` keyword
▹Static & Final keywords in detail
▹The `Object` Class (`equals()`, `hashCode()`, `toString()`)
▹Mini-Project: Library Management System

2

Strings & Collections Framework

3 weeks

▹String Immutability
▹StringBuilder & StringBuffer
▹Collections Framework Hierarchy
▹List Interface (ArrayList, LinkedList, Vector)
▹Set Interface (HashSet, TreeSet, LinkedHashSet)
▹Map Interface (HashMap, TreeMap, LinkedHashMap)
▹Queue Interface (PriorityQueue, ArrayDeque)
▹Stack Class
▹Iterators & For-Each loop
▹Comparable & Comparator Interfaces
▹Mini-Project: Contact Book using HashMap

3

Exception Handling

2 weeks

▹Errors vs Exceptions
▹Exception Hierarchy (Throwable, Exception, Error)
▹Checked vs Unchecked Exceptions
▹Try, Catch, Finally blocks
▹Multiple Catch Blocks
▹The `throw` & `throws` keywords
▹Creating Custom Exceptions
▹Try-with-resources statement
▹Best Practices for Exception Handling

4

File Handling & I/O Streams

2 weeks

▹I/O Streams (Byte Streams, Character Streams)
▹Reading & Writing Files (FileInputStream, FileOutputStream)
▹Buffered Streams (BufferedReader, BufferedWriter)
▹File Class for file operations
▹Scanner for reading files
▹Serialization & Deserialization
▹Introduction to Java NIO (Path, Files)
▹Mini-Project: File-based Note Taking App

5

Generics, Enums & Annotations

2 weeks

▹Generics in Java (Generic Classes, Methods, Interfaces)
▹Wildcards (? extends T, ? super T)
▹Type Erasure
▹Enums (Enumerations)
▹Annotations (Built-in and Custom)
▹Inner Classes (Static Nested, Non-static/Inner, Local, Anonymous)

6

Date & Time API

1 week

▹Legacy Date/Calendar vs New API
▹`java.time` package
▹LocalDate, LocalTime, LocalDateTime
▹ZonedDateTime & Timezones
▹Period & Duration
▹Formatting and Parsing Dates (DateTimeFormatter)

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