new: addigg printing numbers with method reference and lambdas furthe…

[durgesh137]

Print numbers with traditional approach, further with method reference, lambda expression.
Then comparing both traditional and functional approach to understand which is faster.
Traditional is faster

[Copilot]

Pull request overview

This PR introduces a comprehensive Java 8 Stream API learning module focused on comparing traditional (pre-Java 8) and functional programming approaches. It adds the first practice problem (Q001: Print Numbers) along with supporting documentation and templates for future problems. The module aims to help developers understand when and how to use Stream APIs by providing side-by-side comparisons with traditional for-loop implementations, including performance analysis.

Key Changes

• Added Q001 Print Numbers example with three implementations: traditional for-loop, Stream API with method references, and Stream API with lambdas
• Created comprehensive comparison runner with performance benchmarking and detailed analysis of pros/cons for each approach
• Introduced structured documentation including README updates, problem template guide, and learning path structure

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
PrintNumbersTraditional.java	Implements traditional for-each loop approach for printing numbers from a list
PrintNumbersStream.java	Demonstrates Stream API approaches using both method references and lambda expressions
PrintNumbersComparison.java	Provides comprehensive comparison with performance testing, JIT warmup, and detailed pros/cons analysis
README.md	Updates module documentation with project structure, learning approach, and Java 8 resources
PROBLEM_TEMPLATE.md	Introduces standardized template for adding new practice problems with best practices
LEARNING_STRUCTURE.md	Documents the complete learning structure, current status, and roadmap for future problems

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[Copilot]

Missing space after comma in the numbers list initialization. For consistency and readability, add a space after the comma between '10' and '1'.

Current: ..., 9, 10,1, 2, ...
Suggested: ..., 9, 10, 1, 2, ...

Suggested change

	List<Integer> numbers = Arrays.asList(1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10,1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10);
	List<Integer> numbers = Arrays.asList(1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10, 1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10);

[Copilot]

Missing space after comma in the numbers list initialization. For consistency and readability, add a space after the comma between '10' and '1'.

Current: ..., 9, 10,1, 2, ...
Suggested: ..., 9, 10, 1, 2, ...

Suggested change

	List<Integer> numbers = Arrays.asList(1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10,1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10);
	List<Integer> numbers = Arrays.asList(1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10, 1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10);

[Copilot]

The printTraditionalSilent method only calls toString() on the number without assigning the result. This is a no-op operation that the JIT compiler may optimize away, making the performance comparison potentially invalid.

Consider either:

1. Assigning the result to prevent optimization: String result = number.toString();
2. Using a volatile field to store results: volatile String result; and then result = number.toString();
3. Using a blackhole pattern if available

This ensures the work is actually performed during benchmarking.

[Copilot]

The printStreamSilent method only calls toString() on the number without using the result. This is a no-op operation that the JIT compiler may optimize away, making the performance comparison potentially invalid.

Consider either:

1. Using map(Object::toString).collect(Collectors.toList()) to ensure the work is performed
2. Using a volatile field to accumulate results
3. Using a blackhole pattern if available

This ensures the work is actually performed during benchmarking.

[Copilot]

Inconsistent hyphenation in "Side-by-side" vs "side-by-side". For consistency within the same document, use lowercase "side-by-side" as it appears in line 145.

Current: Side-by-side comparison
Suggested: side-by-side comparison

Suggested change

	- `XxxComparison.java` - Side-by-side comparison with performance
	- `XxxComparison.java` - side-by-side comparison with performance

[Copilot]

Missing space after comma in the numbers list initialization. For consistency and readability, add a space after the comma between '10' and '1'.

Current: ..., 9, 10,1, 2, ...
Suggested: ..., 9, 10, 1, 2, ...

Suggested change

	List<Integer> numbers = Arrays.asList(1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10,1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10);
	List<Integer> numbers = Arrays.asList(1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10, 1, 2, 1, 3, 2, 4, 5, 6, 2, 2, 7, 8, 4, 9, 10);

[Copilot]

Missing space after the + operator. For consistency with Java code formatting standards, add a space: number + "," instead of number+",".

This improves readability and follows common Java formatting conventions.

Suggested change

	System.out.print(number+",");
	System.out.print(number + ",");