new: added map and max min methods from stream apis

[durgesh137]

Q003_square_nums/ # ✅ Sum of squares
Q004_max_min/ # ✅ Find max & min

[Copilot]

Pull request overview

This PR adds two new Stream API learning examples (Q003: Sum of Squares and Q004: Max & Min) to the Java 8 educational module, completing the initial set of four problems. Each problem follows the established pattern of providing Traditional, Stream, and Comparison implementations to help learners understand the differences between imperative and functional programming styles in Java 8.

Key Changes

• Q003 Sum of Squares: Demonstrates map() transformation and sum() terminal operations for calculating sum of squared values
• Q004 Max & Min: Shows max() and min() terminal operations with Optional handling for finding extreme values
• Utility enhancements: Added helper methods for printing arrays and generating random test data for performance comparisons

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 13 comments.

Show a summary per file

File	Description
ComparisonUtils.java	Added printNumbers() and getArrayOfSpecifiedSize() utility methods for array operations and test data generation
Pair.java	New helper class to encapsulate min/max result pairs
MaxMinNumberTraditional.java	Traditional single-pass approach to find max and min values
MaxMinNumberStream.java	Stream API implementation using max() and min() with Optional handling
MaxMinNumberComparison.java	Performance benchmarks comparing both approaches across multiple dataset sizes
SumOfSquareOfNumberTraditional.java	Traditional for-loop approach to sum squared values
SumOfSquareOfNumberStream.java	Stream API using map() and sum() for functional transformation
SumOfSquareOfNumberComparison.java	Side-by-side performance comparison with timing metrics
SumOfSquareOfNumber.java	Empty placeholder class removed
README.md	Comprehensive updates including project structure, build instructions, IDE setup, troubleshooting, and current status
PROBLEMS.md	Added detailed documentation for Q003 and Q004 with examples, concepts covered, and performance notes

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[Copilot]

Missing space after number before the + operator. Should be number + "," for consistency with Java style conventions.

Suggested change

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

[Copilot]

The Javadoc comment is missing the @param description text. It should include a description like @param numbers the array of integers to print.

Suggested change

	* @param numbers
	* @param numbers the array of integers to print

[Copilot]

The Javadoc is incomplete. Both @param size and @return tags are missing their descriptions. Should include descriptions like:

• @param size the number of elements in the array
• @return an array of random integers in the range [-100, 100]

Suggested change

	* method to generate an array of specified size with random integers.
	* @param size
	* @return
	* Method to generate an array of specified size with random integers.
	* @param size the number of elements in the array
	* @return an array of random integers in the range [-100, 100]

[Copilot]

[nitpick] Method naming could be improved. The name getArrayOfSpecifiedSize is verbose. Consider a more concise name like generateRandomArray or createRandomIntArray which better conveys the method's purpose.

Suggested change

	* method to generate an array of specified size with random integers.
	* @param size
	* @return
	*/
	public static int[] getArrayOfSpecifiedSize( int size) {
	* Generate an array of specified size with random integers.
	* @param size the size of the array to generate
	* @return an array of random integers
	*/
	public static int[] generateRandomIntArray(int size) {

[Copilot]

[nitpick] Consider making the Pair class immutable by removing the setters (setMinElement() and setMaxElement()). Since this class represents a result value that shouldn't change after creation, immutability would be more appropriate and prevent accidental modifications.

Suggested change

	public void setMinElement(int minElement) {
	this.minElement = minElement;
	}
	public int getMaxElement() {
	return maxElement;
	}
	public void setMaxElement(int maxElement) {
	this.maxElement = maxElement;
	}
	public int getMaxElement() {
	return maxElement;
	}

[Copilot]

The class is missing a class-level Javadoc comment. Since this is a new public class used as a data holder, it should have documentation explaining its purpose, e.g., "Represents a pair of minimum and maximum integer values."

Suggested change

	/**
	* Represents a pair of minimum and maximum integer values.
	*/

[Copilot]

[nitpick] The class name Pair is too generic and could be confused with utility Pair classes from other libraries. Consider a more descriptive name like MinMaxPair or MinMaxResult that clearly indicates it holds min/max values.

Suggested change

	public class Pair {
	private int minElement;
	private int maxElement;
	public Pair(int minElement, int maxElement) {
	public class MinMaxPair {
	private int minElement;
	private int maxElement;
	public MinMaxPair(int minElement, int maxElement) {

[Copilot]

Missing space after comma in the array initialization. Should be {45, 22, 89, 11, 67, 34, 90, 5, -121, 342, 0, 9999, -5000} for consistent formatting.

Suggested change

	int[] numbers = {45, 22, 89, 11, 67, 34, 90, 5,-121, 342, 0, 9999, -5000};
	int[] numbers = {45, 22, 89, 11, 67, 34, 90, 5, -121, 342, 0, 9999, -5000};

[Copilot]

Missing empty array validation. The method will throw ArrayIndexOutOfBoundsException if numbers is empty when accessing numbers[0] on lines 28-29. Consider adding a check like:

if (numbers == null || numbers.length == 0) {
    return new Pair(0, 0); // or throw IllegalArgumentException
}

This would make the behavior consistent with the Stream approach which handles empty arrays using orElse(0).

Suggested change

	*/
	*/
	if (numbers == null || numbers.length == 0) {
	return new Pair(0, 0);
	}

[Copilot]

The variable 'number' is only assigned values of primitive type and is never 'null', but it is declared with the boxed type 'Integer'.

Suggested change

	for (Integer number : numbers) {
	for (int number : numbers) {