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and methods via reflection

This demo showcases how to use Java
Reflection API to inspect the
internal structure of the ArrayList class.

Key highlights:
• Obtains the Class object for java.util.ArrayList using ArrayList.class.
• Retrieves all declared constructors with getDeclaredConstructors().
• Retrieves all declared methods with getDeclaredMethods().
• Iterates over constructors and methods, printing their names.

Why this is useful:
• Demonstrates reflection capabilities for runtime class inspection.
• Helps understand how many constructors and methods exist inside
  core library classes like ArrayList.
• Useful for debugging, framework design,
and meta-programming tasks
where behavior adapts based on runtime
class analysis.

Output:
- Prints the list of all constructor
signatures of ArrayList.
- Prints the names of all methods (public,
protected, private, and package-private declared within ArrayList).

Signed-off-by: https://github.com/Someshdiwan <[email protected]>
…and Generics

What
- Added a detailed documentation file covering three foundational Java concepts:
  1. Streams → declarative, functional data processing with filter/map/reduce and parallelism.
  2. Collections Framework → core data structures (List, Set, Map, Queue) and their integration in back-end, front-end, and frameworks.
  3. Generics → type-safety, reusability, and readability improvements with generic classes/interfaces.
- Included structured sections:
  - Concept explanation
  - Practical applications
  - Real-world usage across back-end, microservices, UI, and middleware.
- Provided a concise summary that positions these three concepts as the backbone of scalable Java development.

Why
- These three concepts are central to modern Java programming across domains.
- Developers often use them together (e.g., Collections hold data, Streams process it, Generics enforce type safety).
- A unified overview makes it easier to understand how they interconnect and why mastering them is essential for enterprise-grade applications.

Logic
1. **Streams**
   - Emphasized functional, declarative style over imperative loops.
   - Highlighted back-end data manipulation, parallel computation, and event/log pipelines.
   - Showed relevance in high-throughput systems like Spring Boot services or analytics.

2. **Collections Framework**
   - Identified as the backbone of Java applications.
   - Explained usage in back-end (DB results, caching), front-end/mobile (UI state, adapters), and frameworks (Spring, Hibernate).
   - Reinforced importance as building blocks for nearly all Java data-handling code.

3. **Generics**
   - Explained compile-time type safety preventing runtime ClassCastException.
   - Showed reusability via type-safe repositories, DTOs, and custom utilities.
   - Clarified benefits of reduced boilerplate and increased readability.

4. **Real-World Applications**
   - Connected Streams, Collections, and Generics into enterprise workflows:
     - Back-end data processing (Collections + Streams).
     - Microservices aggregation (Streams + Generics for DTOs).
     - UI/mobile apps (Collections + Generics for model binding).
     - Utility libraries (all three for flexibility and safety).

Real-life applications
- Enterprise back-end: Streams filter/aggregate DB records, Collections cache them, Generics enforce DTO typing.
- Microservices: Streams combine service results, Generics enable reusable interfaces across APIs.
- UI/Mobile apps: Collections model UI data, Streams transform it, Generics prevent runtime casting errors.
- Middleware/utility libraries: Provide type-safe, reusable APIs built on Collections and Generics.

Notes
- ✔ Streams = declarative, functional pipelines for data.
- ✔ Collections = robust, reusable data structures.
- ✔ Generics = compile-time safety + reusable APIs.
- Together, these form the core triad for efficient, scalable, and maintainable Java systems.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>
…with Java examples

What
- Documented the concept of **Declarative Programming** vs **Imperative Programming**.
- Highlighted key characteristics:
  - Focus on *what* to achieve, not *how* to achieve it.
  - High-level abstraction with less boilerplate code.
  - Execution strategy left to underlying system (e.g., SQL engine, Streams).
- Provided concrete examples across multiple domains:
  - **SQL** → `SELECT * FROM students WHERE marks > 90` (declarative query).
  - **Java Streams** → `list.stream().filter(...).map(...).toList()` (functional transformations).
  - **HTML/CSS** → structure and styling declaratively described.
- Outlined benefits:
  - Conciseness, readability, maintainability.
  - Easier parallelization via declarative APIs.
- Added **Java-specific comparison**:
  - Imperative sum of even numbers (loops + conditions).
  - Declarative sum using Streams API (`filter`, `mapToInt`, `sum`).

Why
- Declarative programming is central to modern Java (Streams, Lambdas, functional style).
- Developers often confuse *control flow* with *business logic*; declarative style separates the two.
- This doc clarifies when and why declarative approaches are preferred in enterprise apps.

Logic
1. **Definition**
   - Declarative = specify outcome, not steps.
   - Contrasted with imperative = specify exact flow (loops, state changes).

2. **Key Characteristics**
   - Abstraction of execution.
   - Focus on results instead of algorithmic details.
   - Reduction of verbosity and control structures.

3. **Examples**
   - SQL → declare query logic without procedural fetch.
   - Streams → pipelines describe transformation, not iteration.
   - HTML → structure declaration, not rendering process.

4. **Java Focus**
   - Streams API embodies declarative patterns (map/filter/reduce).
   - Shows improved readability and parallelization compared to traditional loops.

Real-life applications
- **Database queries (SQL)**: write intent-driven queries, let DBMS handle execution plan.
- **Back-end APIs (Java Streams)**: declarative transformations for business rules.
- **UI layer (HTML/CSS)**: declaratively specify layout and style, browsers handle rendering.
- **Parallel data processing**: declarative pipelines allow frameworks to optimize multithreaded execution.

Notes
- Declarative ≠ “no control,” but rather offloading control to libraries/engines.
- Imperative code is sometimes necessary for low-level optimization, but declarative style is preferred for clarity.
- Java’s `Stream.parallel()` demonstrates how declarative style enables automatic performance improvements.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>
…am, LongStream, DoubleStream)

What
- Documented **Primitive Streams in Java** and their role in numerical data processing.
- Covered:
  - Definition and difference from object-based streams.
  - Specialized types: IntStream, LongStream, DoubleStream.
  - Built-in numeric methods (sum, average, min, max, summaryStatistics).
  - Benefits: performance optimization, readability, specialized numeric APIs.
- Explained real-world applications across back-end systems, analytics, financial apps, and middleware.
- Provided example using IntStream.rangeClosed(1, 100).sum().
- Added notes on integration with other APIs (boxed conversion, Collectors aggregation).

Why
- Standard `Stream<Integer>` incurs autoboxing/unboxing overhead, reducing efficiency in numeric-heavy workloads.
- Primitive Streams solve this by working directly with primitives (int, long, double).
- They are critical in performance-sensitive domains such as analytics, finance, and real-time monitoring.
- Understanding their role ensures developers can write cleaner, faster, and more maintainable numeric pipelines.

Logic
1. **Specialized Stream Types**
   - `IntStream` → operations on int values.
   - `LongStream` → operations on long values.
   - `DoubleStream` → operations on double values.

2. **Performance Advantage**
   - Avoids autoboxing/unboxing (`int ↔ Integer`).
   - Reduces memory usage and GC pressure.
   - Better suited for large-scale numeric operations.

3. **Built-in Numeric Methods**
   - Directly provides `sum()`, `average()`, `min()`, `max()`, and `summaryStatistics()`.
   - Eliminates need for manual reduction/aggregation logic.

4. **Integration**
   - `boxed()` → converts primitive streams to object streams when APIs require `Stream<T>`.
   - Works seamlessly with Collectors for statistical reporting.

Real-world applications
- **Back-End Processing**: Sales aggregation, DB report generation.
- **Financial Systems**: Risk models, moving averages, high-frequency trading data.
- **Analytics/Scientific Computing**: Sensor data, simulations, dashboards.
- **Middleware/Utilities**: Reusable numeric helper APIs, parallel data crunching.

Notes
- Prefer primitive streams for numeric-heavy workloads.
- Use `parallel()` when large datasets benefit from multicore processing.
- Convert to boxed streams only when integration requires object types.
- Leverage `summaryStatistics()` for concise statistical reporting.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>
LF in the repo. now Windows file support
can clone repo.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>
banner: continuous loop
animation + clickable
link in README.md.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>
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