A structured, step-by-step roadmap to master Java from fundamentals to advanced Data Structures & Algorithms — with clean implementations and interview-focused practice.
✔ Beginners starting Java
✔ Students preparing for placements
✔ Developers strengthening fundamentals
✔ Interview preparation
✔ Anyone who prefers structured learning
This is not random code.
This is organized progression.
START
│
▼
┌──────────────────────────┐
│ 01. Java Basics │
│ Variables, Loops, Arrays │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 02. OOP (Core Java) │
│ Classes, Inheritance │
│ Polymorphism, Interfaces │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 03. Time & Space │
│ Big-O, Complexity │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 04. Recursion │
│ Call Stack, Base Case │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 05. Divide & Conquer │
│ Merge Sort, Quick Sort │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 06. Linear DS │
│ ArrayList, LinkedList │
│ Stack, Queue │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 07. Hashing │
│ HashMap, HashSet │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 08. Trees │
│ Binary Tree, BST, Heaps │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 09. Greedy & Backtracking│
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 10. Graphs │
│ BFS, DFS, Topo Sort │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 11. Dynamic Programming │
│ Memoization, Tabulation │
└──────────────────────────┘
│
▼
┌──────────────────────────┐
│ 12. Advanced Structures │
│ Tries, Segment Trees │
└──────────────────────────┘
│
▼
🎯 INTERVIEW READY
java-core-to-advanced/
│
├── 01-basics/
├── 02-variables-and-data-types/
├── 03-operators/
├── 04-conditional-statements/
├── 05-loops-and-flow-control/
├── 06-pattern-programs/
├── 07-functions-and-methods/
├── 08-arrays/
├── 09-sorting/
├── 10-2d-arrays/
├── 11-strings/
├── 12-bit-manipulation/
│
├── 13-oops/
├── 14-time-and-space-complexity/
├── 15-recursion/
├── 16-divide-and-conquer/
├── 17-arraylist/
├── 18-linked-list/
├── 19-stack/
├── 20-queue/
├── 21-hashing/
├── 22-binary-trees/
├── 23-bst/
├── 24-heaps/
├── 25-greedy/
├── 26-backtracking/
├── 27-graphs/
├── 28-dynamic-programming/
├── 29-tries/
├── 30-segment-trees/
│
└── README.md
Each folder contains:
- Clean Java implementations
- Proper comments
- Structured naming (PascalCase)
- Practice problems
- Progressive difficulty
public static boolean isEven(int num) {
return (num & 1) == 0;
}public static int getIthBit(int num, int i) {
return (num >> i) & 1;
}git clone https://github.com/PavithraSharma14/java-core-to-advanced.git
cd java-core-to-advancedRecommended:
- IntelliJ IDEA
- VS Code
- Eclipse
Start from:
01-basics → move sequentially
Do not skip complexity + recursion before advanced topics.
| Stage | Topic | Status |
|---|---|---|
| 1 | Basics | ✅ Completed |
| 2 | OOP | ✅ Completed |
| 3 | Time & Space | ⏳ Planned |
| 4 | Recursion | ⏳ Planned |
| 5 | DSA | ⏳ In Progress |
To maximize results:
- Read the concept
- Run the code
- Modify it
- Solve practice problems
- Re-implement without looking
- Track your complexity
Consistency > Speed
Structure > Random Learning
- Structured learning path
- Interview-focused progression
- Clean naming conventions
- Progressive module system
- Covers fundamentals to advanced DSA
Contributions are welcome.
Guidelines:
- Follow folder structure
- Maintain clean code
- Use PascalCase for file names
- Add meaningful comments
- Keep logic readable
MIT License
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